Appendix 1 Glossary of Terms

Agitator A type of mechanical mixing device; used in copiers in the toner supply to keep toner particles separated; also used in the development unit to combine toner and carrier, creating two—component developer. AI Short Protocol Artificial Intelligence Short Protocol reduces the time required for the protocol exchange with a particular terminal by saving the communication parameters and the modem rate used to send the last page of a transmission. These parameters are used for the start of the next transmission to that terminal. Air Knife (or Air The air knife paper separation process uses jets of air to separate sheets of paper for Separation) paper feed. Attenuation After the modem converts data to serial and modulates it, the data passes through an attenuator, which adjusts the TX level. Auger A screw-like mechanical transport device used to move bulk materials in many different applications. It relies on a large screw with deep, wide-pitched threads turning inside a close-fitting cylinder. The threads act like an endless or wedge to lift material from one end of the cylinder to the other. Automatic Document A motorized device that allows automatic feeding, alignment and stacking of multiple Feeder (ADF) originals, greatly improving the overall efficiency of photocopying.

10 March 2004 1 Appendix 1 Glossary of Terms

Automatic Document An advanced type of document feeder that can recycle and reverse originals. Handler (ADH) Autorouting When a G3 fax message with a SUB code is received, the machine compares it with the personal codes stored in the machine with e-mail addresses. If there is a match, the machine automatically routes the message to that e-mail address. Baud Rate The Baud Rate is the number of bits per second divided by the number of bits per Baud. Bias Roller A bias roller is a roller that has a constant electric voltage applied to it. Such rollers are used at various places in copiers and printers. A typical use is in a copier’s cleaning system, where a bias roller is often used to attract toner removed by a cleaning blade or brush. Bipolar Junction A bipolar junction contains two junctions between p and n type Transistor semiconductor, and three (the collector, the base, and the emitter). See . Block Diagram A kind of electronic map that divides a system into a number of functional “blocks”; it shows all the interconnections among the blocks, but generally does not show detail inside them. Bond A category of papers, consisting of many individual types. Most bond papers are suitable for use in plain-paper copiers. The voltage at which current will flow in reverse through a . Regular will generally be destroyed if a reverse voltage greater than the breakdown voltage is applied; however, zener diodes are designed to operate at the breakdown voltage. See .

10 March 2004 2 Appendix 1 Glossary of Terms

Brushless DC Motor In standard DC motors, the magnet is stationary while the coil rotates, and brushes complete the electrical contact to the rotor. However, In a brushless DC motor, the coil is stationary and the magnet moves. Call Collision After the scanning the document, the machine checks whether there is an incoming Prevention fax message. The machine cannot dial if there is an incoming message. This differs between North American, and European and Asian models. See North American models and European and Asian models. Carrier (copiers) Carrier is one of the components of a two-component developer. Carrier consists of tiny iron-based beads that attract toner particles through a triboelectric charge and transport them to the photoconductor during the development process. See Triboelectric Charge. Carrier (facsimile) The carrier is the base frequency wave that fax machines use for communication. To transmit data, fax machines superimpose a modulating signal onto the carrier wave by varying the frequency, amplitude, or phase (or a combination of these) in a standard manner. See Modulation Techniques. A microprocessor chip that is used as the primary control and information processing (CPU) device in a sophisticated electronic system. Charge The first step in the copy process; during the charge process, an even electrical charge is applied to the photoconductor, preparing it to receive the image of an original during exposure. Charge Corona Unit A corona unit used for the first step in the copy process, to apply an even high— voltage charge to the photoconductor; usually ventilated by a blower to help distribute ions during charging.

10 March 2004 3 Appendix 1 Glossary of Terms

Charge Coupled A solid-state component made from a number of very small -sensitive elements; Device (CCD) the amount of light falling on each element produces an electrical signal of corresponding strength. CCDs are used in -based copiers, fax machines and some cameras. Cleaning That step in the copy process during which residual toner particles—those left behind after image transfer—are removed from the photoconductor. Cleaning relies mainly on mechanical systems but electrostatic forces may also be used. Cleaning Blade An element in a copier’s cleaning system. After a copy has been made, the cleaning blade acts like a windshield wiper, riding along the surface of the photoconductor to wipe off all remaining toner particles. Cleaning Brush An element in a copier’s cleaning system. After a copy has been made, the cleaning brush removes the residual toner from the surface of the photoconductor. See Bias Roller. Clutch A control device for rotational movement; a clutch will either be engaged, locking its components together and transferring rotation, or disengaged, letting its components turn separately and preventing the transfer of rotation. Clutch, Magnetic See Magnetic Clutch. Clutch, Magnetic See Magnetic Spring Clutch Spring Clutch, Slip See Torque Limiter Clutches. See Slip Clutch. Clutch, Spring See Spring Clutch. Clutch, Torque Limiter See Torque Limiter Clutches.

10 March 2004 4 Appendix 1 Glossary of Terms

Coefficient of Friction The coefficient of friction directly affects the efficiency of paper feeding. It must be high (of paper) enough that the feed and transport rollers can get a good grip. However, it must be low enough that the sheets of paper slip over each other. Cold A variation of the . See Fluorescent Lamps, Applications. Fluorescent Lamp Contact Image Sensor The contact image sensor (CIS) is a compact image reading assembly containing an LED array, an array of self-focusing optic fibers (SELFOC), and a strip of light (CIS) detectors, such as phototransistors. The CIS is used instead of the CCD in the most compact of fax machines. Corona Unit A copier component that uses a high electrical voltage to create a localized electrical field of charged ions; various kinds of corona units are used at different points in the copy process. See Pre-Cleaning, Quenching, Transfer And Separation Corona Units. Corona A thin wire usually made from tungsten and coated with carbon. Mounted inside a corona unit, it carries the high voltage needed to generate an electrical field for a specific copier application. Cross Mixing The process by which toner and carrier are mixed together inside a copier; also creates and distributes the triboelectric charge that binds the toner to the carrier particles. Current The rate of flow of electricity through a conductor; current is measured in Amperes or Amps. Data Compressor and Part of a fax circuit; it compresses the data before sending it out over the telephone Reconstructor - DCR line. It also reconstructs compressed data coming in from the telephone line. DC Motor A motor that operates on .

10 March 2004 5 Appendix 1 Glossary of Terms

DC motor, Brushless See Brushless DC motor. Developer, See Mono-component Developer. Mono-component Developer, Also called dual-component developer. See Two-component Developer. Two-component Development That step in the copy process which first produces a visible image on the photoconductor. During development, toner is applied to the photoconductor, where it is electrically attracted to the latent image formed during exposure. Development Roller Part of a copier’s development system. Development rollers use some combination of magnetism, triboelectric charge and/or bias voltage to apply toner to the latent image on the photoconductor. Diode A p-type semiconductor joined to an n-type semiconductor. A diode allows current to move in only one direction. See Diodes. Diode, Zener See Zener Diode. DNS Domain Name System is a service that enables the IP address to be obtained from the host under the TCP/IP network environment. Doctor Blade Part of a copier’s development system. It limits the thickness of developer picked up by the development roller by scraping off the excess as the roller turns. It determines the height of the magnetic brush. Dual Component Toner Toner designed to work in a dual-component development system. This toner is similar to the non-magnetic type monocomponent toner. It works with a separate particle known as a carrier. The mixture of toner and carrier is known as developer.

10 March 2004 6 Appendix 1 Glossary of Terms

Duplex Unit A paper handling device that permits the making of two-sided copies without manual intervention by the user. Available through the installation of a peripheral duplex unit on mid-size copiers, duplexing is a standard feature on most high-volume machines. Duplexing Making two-sided copies. ECM Memory Error Correction Mode memory, an optional extension to Group 3 protocol, is a countermeasure for the frequent data errors that occur in areas that suffer from noisy telephone lines. See ECM. Electromagnetic Clutch A type of clutch which contains its own electromagnetic actuator. When the clutch’s coil is energized, two metal plates are pulled together and transmit rotation to a given component. When not energized, the two plates are separated by a spring, and no rotation is transmitted. E-mail Electronic mail is a system in which messages in the form of digital data are sent and received between computers. Erase Lamp A component which removes certain parts of the latent image after exposure. After considering reproduction ratio and paper size, the main control board turns on specific sections of the erase lamp to remove the charge from the photoconductor outside the desired image area. Estimated Fillbit This process was developed by Ricoh to improve the efficiency of MH, MR, and MMR Control-EFC coding. Ethernet This is the most commonly used LAN. See Ethernet Frame Structure. Exposure A process where light is applied to a photoconductor to create a latent reverse image in the form of a charge pattern on the surface of the photoconductive material. See Photocopying Processes.

10 March 2004 7 Appendix 1 Glossary of Terms

Exposure Lamp Part of a copier’s exposure and optical systems; provides the necessary illumination to create a reflected image from an original, which in turn creates an electrical latent image on the photoconductor. Fax On Demand-FOD A polling application with pre-recorded voice assistance. FRR Paper Feed One of the standard paper feeding systems; the FRR (feed and reverse roller) feed mechanism consists of a pick-up roller, a feed roller, and a reverse roller. Feed Roller The first roller to handle paper a copier’s paper feed system; pulls individual sheets from a paper supply, feeding them into the copier where they are passed to other rollers in the paper path. FIFO Memory First-In First-Out Memory synchronizes the transfer of video data to (transmission) or from (reception) the modem. Fluorescent Lamp A lamp consisting of a gas-filled, closed glass tube that has electrodes at each end and an internal coated surface of a phosphorous material. Frequency Shift Keying Frequency shift keying (FSK) is s type of frequency modulation that is used for transmitting digital signals. Fusing The step in the copy process that bonds toner to a sheet of paper. Heat and pressure melt toner and force it into the paper surface, creating a copy that meets or exceeds the durability of the original. Fusing Lubrication Part of a copier’s fusing system, needed to keep toner from sticking to the fusing System rollers. Uses an absorbent pad and/or a blade to coat the rollers with silicone oil. Gray Scale A row of small test patches showing a full range of image density, from solid black to paper white, usually in five to ten steps. Printed on a copier test chart. It is a gauge for the side-to-side and overall image density of the machine.

10 March 2004 8 Appendix 1 Glossary of Terms

Grid Plate Part of the charging system in copiers that use an Organic Photoconductor (OPC). OPCs are more sensitive to high voltage charges, so the grid plate acts as a regulator between the OPC surface and the charge corona. Hall Effect Sensors Hall effect sensors are used in some network control units (NCU) of fax machines to detect line current. An incandescent lamp filled with halogen gas. Hot Roller The part of a copier’s fusing system that contains the fusing heat source, usually a halogen lamp. The hot roller is usually coated with Teflon, and works with the pressure roller. See Pressure Roller. I/O Rate In fax machines this refers to the amount of time necessary for the scanner or printer to process one scan line of image data. Modulation and demodulation are not included in this time measurement. ID Sensor A photosensor that measures the image density (reflectivity) of the drum and of a test pattern (ID sensor pattern). The output of this sensor is used to control toner supply. ID Sensor Pattern A standard pattern that is exposed and developed for sensing by the ID sensor. Image Density The quality of an original or copy that describes its relative lightness or darkness; high image density refers to a very dark copy, low image density refers to a very light copy Image Density Control The system in a copier that compensates for the variation in reflectivity among different originals. Some adjust the brightness of the exposure lamp. Others regulate toner transfer during development, by adjusting a bias circuit. In either case, image density controls can be manual, automatic or both.

10 March 2004 9 Appendix 1 Glossary of Terms

Interleave Duplexing A duplexing method used by some digital machines that speeds up duplexing by storing original images in memory. Sheets continually feed and reverse without stopping and the correct image for each sheet and side is selected from memory. ITU-T Standards International standards for data communication. JBIG Compression The JBIG compression method consists of four processes: conversion to bi-level data, progressive coding, division into strips, and coding. LAN Local Area Network. See LAN Fax, LAN Basics. Large Capacity Paper A copier peripheral that holds a much greater amount of paper than a standard tray, Tray thereby enabling the copier to run for longer periods without the supply being refilled, typically holds between 500 and 3000 sheets. An LED that outputs laser light. Latent Image A photographic term which refers to an undeveloped image on a piece of film; in xerography, it refers to the invisible, electrostatic image formed on the photoconductor during exposure. LCD LCD is an abbreviation for Liquid Crystal Display. An LCD is a digital display that consists of two sheets of glass separated by hermetically sealed liquid crystal material. The liquid crystal is normally transparent. LCT See Large Capacity Tray. Lead Edge The first paper edge to contact the latent image on the photoconductor. The “front edge” of a copy as it travels through the paper path.

10 March 2004 10 Appendix 1 Glossary of Terms

Lead Edge Erase The removal of that portion of a latent image which corresponds to a narrow strip along the lead edge of the copy, usually no more than 5 mm wide. This prevents a dark line from the edge of the original document from appearing on the copy. Achieved through the action of an erase lamp immediately after the exposure process. Light Emitting Diode A kind of diode that emits photons. Usually shortened to “LED”. LED Array LEDs mounted together in an array as a light source. Line Buffer A memory buffer that ensures synchronization of video data transfer between different components of the circuit. Magnetic Brush A localized concentration of two-component developer formed on the surface of a development roller by magnetic fields. It brushes developer over the photoconductor during the development process. This allows toner particles in the brush to be attracted to the latent image. Magnetic Clutch See Electromagnetic Clutch. Magnetic Similar to the non-magnetic monocomponent toner, this type has iron oxide particles encapsulated in the resin matrix of each individual particle of toner. The toner isn’t Monocomponent Toner actually magnetic itself, but it can be attracted by a magnet. Magnetic Spring Clutch The magnetic spring clutch is a hybrid of the electromagnetic and spring clutches. Unlike the normal spring clutch, the spring is loose when idling. Magnification Lines Two lines of an identical specified length, one vertical and one horizontal, printed on a copier test chart. Used to check the vertical and horizontal magnification of a copier’s optical system.

10 March 2004 11 Appendix 1 Glossary of Terms

Main Control Board A containing the most important components in a copier’s electronic control system, including the Central Processing Unit (CPU), and factory- programmed instructions stored on Read Only Memory (ROM) chips. The main board is linked to other parts of the control system with a number of multi-wire connectors. Master Belt A wide, flexible loop of plastic with an organic photoconductor surface. Modified Huffman This compression method has one-dimensional coding scheme codes scan line data Compression without reference to data on adjacent lines. Microswitch Microswitches are electromechanical switching devices containing two contacts. MIME Multipurpose Internet Mail Extensions is a specification for the inclusion of various types of data in e-mail. Modified MR The Modified MR method uses the same algorithm as the MR method, but has 6 main Compression differences. Modulating Signal The data signal from the fax machine. See Modulation Techniques. Moisture Content Moisture content directly affects paper transport, copy quality, and curl. The generally (of paper) acceptable range is 4 ~ 6 percent moisture. See Paper Characteristics. Monocomponent Toner A special toner formulation that has both magnetic and electrical properties; functions without carrier. See Monocomponent Developer. Motor, Stepper See Stepper Motor. Moving Platen A type of scanning optical system in which originals are placed on a glass document surface (the platen) which moves across a fixed exposure slit and lamp during an exposure; found only on relatively small, low-speed copiers.

10 March 2004 12 Appendix 1 Glossary of Terms

Moving Scanner A type of scanning optical system in which originals are placed on a fixed glass document surface, under which is a moving lamp and mirror assembly (the scanner). This scanner moves under the original during an exposure. Found on most medium- to-high speed copiers; this design is also known as “fixed platen” scanning Modified Read This is the Modified Read compression method. It is an expanded form of the one- Compression dimensional run length encoding method. While the MH method encodes pixels in the pixel scanning direction, the MR also takes notice of the pixels in the feed direction. Lamp Similar to the fluorescent lamp, but light emission is from the neon gas rather than the phosphorous inside coating. Network Control Unit Interfaces a fax machine with the telephone network. (NCU) Network Interface The filters, relays, attenuators and other components in these circuits interface the Circuits machine with the public telephone network. New Estimated Fillbit Fill bits are never added to the data and the receiver uses the SAF memory or hard Control disk instead of the FIFO memory. If the receiver's memory is full, it sends PIN to the transmitter and the line is disconnected. Non-magnetic All-in-One toner that contains pigments for printing in a matrix of resin. This kind of toner usually comes in a cartridge and is used with non-magnetic rollers. Monocomponent Toner Offset Image A partial image that remains on the photoconductor or fusing rollers due to incomplete cleaning and is transferred to subsequent copies. Opacity of Paper Paper must be sufficiently opaque to prevent image show through. This is especially important in paper used for duplexing. Most brands of paper use some kind of filler to enhance opacity. See Paper Characteristics.

10 March 2004 13 Appendix 1 Glossary of Terms

Organic A type of photoconductor based on certain organic chemicals, rather than metallic Photoconductor (OPC) elements like selenium or silicon. An OPC requires negative charging before exposure. It is generally non-toxic, enabling it to be handled and disposed of more easily than selenium types. Over-toning A condition that occurs when a copier’s toner supply system is delivering too much toner to the development unit; the excess toner builds up inside the copier, especially around the photoconductor and paper path. Paddle Roller Part of the development unit of many copiers. It pushes charged developer (a mix of toner and carrier) against the development roller, which picks up the developer through magnetic attraction and brushes it over the latent image. Paper Brightness The brightness of a paper is a measure of its light reflectivity. See Paper Characteristics. Paper Curl Curl in paper is a major cause of transport problems resulting in misfeeds. See Paper Characteristics. Paper Feed System The various rollers, belts, sensors and control devices that are responsible for moving sheets of paper through the copier; begins with the paper supply, and ends with the exit tray or sorter that holds the finished copies. See Paper Feed Paper Size There are several standard systems for measuring paper size. The most commonly used is the ISO (International Organization for Standardization) series of paper sizes. In the United States, paper sizes are usually measured in inches. Paper Stiffness Paper stiffness is a result of the orientation of the fibers within the paper. Stiffness affects paper feeding and transport in copiers and laser printers. Paper is generally two or three times stiffer in the with grain direction than in the cross grain direction. See Paper Characteristics.

10 March 2004 14 Appendix 1 Glossary of Terms

Paper Weight There are three systems for classifying paper weight. These are the ISO system (g/m2), the USA system (lb), and the Japanese system (Kg). Parallel Circuit A type of electrical connection in which components each have a direct, independent path to a power source. A chemical coating on the inside of a fluorescent tube that produces visible light when struck by radiation. See Fluorescent Lamp. Photoconductor A special material that acts as an insulator in darkness and as a conductor when exposed to light. Photointerrupter An electronic sensors that has a photocell and a light emitting diode (LED) on either side of a small gap. When a tab on a moving component enters the gap, it blocks the light from the LED, shutting off the photocell and signaling the component’s position to the machine’s Main Control Board. Phototransistor A phototransistor works like an ordinary bipolar transistor, except that light shining on the base of the transistor it on. Pick-off Pawls Part of a copier’s paper separation system that provides a mechanical separation method. Pick-off pawls ride along the surface of the photoconductor to peel off any paper not removed electrically. Point-to-point Diagram An electronic map, specially designed for troubleshooting equipment with replaceable circuit boards; combines features of a schematic drawing and a block diagram, concentrating on connections to and from different components.

10 March 2004 15 Appendix 1 Glossary of Terms

Polarity The quality of electricity that describes its tendency to exist in either a positive or negative state. In most electrical circuits, polarity determines the direction of current flow. In electrostatic charges, polarity indicates the charge of ions that make up an electrical field, and therefore determines the polarity of materials that can be attracted by that field. A charge of a given polarity always attracts materials with a charge of the opposite polarity Polyphase Shift Keying A type of phase modulation (PM) where data modulation occurs by altering the phase of the carrier wave and frequency remains constant. POP Post Office Protocol servers are computers that receive mail using SMTP. The mail includes a setting to ensure that it is directed to the POP server. POP servers are used when the user is not permanently connected to the internet. Pre-cleaning Corona A corona unit used just before cleaning in the copy cycle. It creates an electrical field Unit that reduces the charge on the photoconductor before mechanical cleaning, making it easier to remove leftover toner. Pressure Roller Part of a copier’s fusing system. During fusing, toner is forced into the surface of the paper by two rollers, the pressure roller and the hot roller. The pressure roller is usually made of silicon rubber, to help it withstand heat and provide a good grip on the paper. See Hot Roller. Pre-transfer Lamp Used in some copiers to reduce the charge of the latent image after development, weakening its attraction just enough to assure a clean transfer. It also prevents toner particles from being attracted back to the photoconductor during separation. Process Control Process control is a system that automatically changes machine processes to compensate for changes in the environment or the machine condition.

10 March 2004 16 Appendix 1 Glossary of Terms

Protocol Signals Fax machines use two types of signals: Single (short, timed transmitted tones like CED and CNG) and frame-like HDLC signals that transmit digital information like DIS and NSF. PSTN Public Switched Telephone Network Quadrature Amplitude QAM is a combination of amplitude modulation (AM) and phase modulation (PM). Modulation (QAM) Quenching Quenching is the process that eliminates any residual electric charge remaining on the photoconductor after the cleaning process. Quenching prepares the photoconductor for the charge step of the next copy or print cycle. Quenching Corona A corona used at the end of the copy process; it creates an electrical field to help remove latent image charge on the photoconductor after mechanical cleaning, preparing the surface for the next copy cycle; always used in conjunction with a quenching lamp Quenching Lamp Shines light on the surface of the photoconductor to remove the latent image, after the leftover toner has been removed by the cleaning system. See Quenching. Reception Modes There are two types of reception modes: manual (telephone mode) and automatic (fax mode). Reed Reed switches are magnetically operated switches with contacts hermetically sealed in a glass capsule. Reflective Photosensor Reflective photosensors are short-range sensors that have a light emitting element (usually an LED) and a light sensitive element (usually a phototransistor).

10 March 2004 17 Appendix 1 Glossary of Terms

Registration The process by which paper is lined up properly with the developed image on the photoconductor; registration is usually accomplished with a system of rollers, mechanical guides and electronic sensors. Registration Marks These marks are printed at the top and side of a copier test chart as a gauge of paper alignment and copier erase margins. They consist of thin parallel lines that will show if the paper is improperly meeting the latent image on the photoconductor. Registration Rollers Part of a copier’s paper feed system. A pair of rollers that align a sheet of paper to remove skew, and then feed the sheet toward the photoconductor at the correct time during the copy cycle to align it with the image on the photoconductor. Registration Sensor Part of a copier’s paper feed system; an electronic sensor mounted in the paper path just before the registration rollers. This sensor alerts the copier’s control system when a sheet of paper approaches the registration rollers, so that they can be stopped before the sheet contacts them. Devices Required to expand LANs. These devices do the following: extend the connection distance, enable connection between networks of different standards, allow control of high-speed transmission routes and filtering. They include repeaters, bridges, switches, gateways and routers. Relay Rollers Part of a copier’s paper feed system; used in machines with long or complex paper paths simply to move sheets from one area to another. They have no special copy- related function. Reproduction Ratio An optical specification that determines the relationship between original size and copy image size. A one-to-one reproduction ratio indicates that the original and copy have the same image size. This ratio can vary in most copiers to produce enlarged and reduced copies.

10 March 2004 18 Appendix 1 Glossary of Terms

Resolution Bars Printed on a copier test chart as a gauge of the overall sharpness of a machine’s optical system; should be clearly visible on copies as individual lines. SAF Memory Store and Forward Memory stores fax messages to send later or for transmission to more than one location. It also holds the incoming message if, for example, the printer is out of paper. Scanner Part of the exposure system in a moving-scanner copier; these exposure systems have two scanners. The first consists of a lightweight metal frame containing one mirror and the exposure lamp. The second has a similar frame and two mirrors. Both scanners move along guide rails during an exposure, and reflect the image between them during the scan to maintain a constant optical distance from the original to the lens. Schematic Diagram The most traditional and detailed type of electronic map; shows every circuit, no matter how complex, and every component, no matter how small. Selenium Drum A commonly used photoconductor. It consists of a hollow aluminum cylinder coated with a layer of selenium-tellurium or selenium-arsenic alloy. The selenium alloy layer provides the key photoconductive property of having high electrical resistance in the dark, and low resistance when exposed to light. SELFOC An acronym for Self-Focusing Fiber Optic Array. SELFOCs are used for strip exposure with fixed optics, in contact image sensors, and direct scanning digital systems. SEP/PWD/SUB/SID The ITU-T recommendations were changed in 1996 to allow polling and confidential Signals communications. At this time, this could only be done between Ricoh-made products. With the institution of these signals, communication between all fax makers became possible. Separation That step in the copy process during which the paper and toner are separated from the photoconductor. See Image Transfer And Paper Separation

10 March 2004 19 Appendix 1 Glossary of Terms

Servomotor Used in many copiers to move scanners in the optical system; servomotors emit a specific number of electrical pulses with each revolution, allowing a control circuit to monitor and regulate their speed. Servomotors use feedback to maintain a constant rotating speed. Setting Powder A dry lubricant powder applied to new photoconductors and or cleaning blades immediately before installation. During initial operation, the powder protects the surface from scratches that might result from contact with other copier components. Slip Clutch Another name for a torque limiter clutch. See Torque Limiter Clutch. SMR Compression The Simple Modified Read method is identical to MR coding except that the K parameter is 8 for Standard and Detail resolution and 16 for Fine. SMTP Simple Mail Transfer Protocol is the protocol for communication between internet mail MTAs (message transfer agents). Solenoid A simple electrical control device, consisting of a hollow electromagnet and a metal plunger. When the magnet is energized, the metal plunger is pulled inside it, triggering whatever mechanism is attached. Sorter A sorter is a paper handling device that feeds finished copies into multiple output bins; can produce sets of collated copies, matching the order of the original documents, or count out stacks of single copies. Spring Clutch A popular clutch for copier applications; its internal components are normally held together by a spring connected to an external sleeve, and rotation is transmitted to a given component. When the sleeve is kept from turning, the spring expands, releasing one internal component and preventing the transfer of rotation. Super Speed Coding The Super Speed Coding method combines EFC with Short Preamble and white line (SSC) Method double-speed processing to achieve a further reduction in transmission time.

10 March 2004 20 Appendix 1 Glossary of Terms

Stator A stationary part of an electric motor in or about which a rotor turns. See DC Motors. Stepper Motor A type of electric motor designed to be controlled in individual steps that are portions of a full rotation, each step as small as one degree of arc. It is often used to adjust lens position in copiers with variable reproduction ratio. The design of a stepper motor allows for extremely precise lens placement and easy electronic control. Stepper motors are used whenever accurate positioning of a component is required. Stripper Pawls Part of a copier’s fusing system; stripper pawls ride along the surface of the hot roller, and peel off copies that stick to the roller despite the roller’s lubrication. Subnet It is difficult for one network to handle 65,534 hosts, therefore the subnet mask creates subnets to take some of the burden off of the main network. See Subnet and Subnet Masks. Subnet Mask Subnet masks divides the host block into a maximum of 255 subnets within which a maximum of 255 hosts can exist. This helps to increase the speed with which a user can access a particular portion of the network. See Subnet and Subnet Masks. Substitute Reception Data is stored in memory as it comes in to avoid loss of data if there is a printer problem. Basically, this means that memory substitutes for the print engine during reception. TCP/IP (Transmission A standard internet protocol supported by Windows 95, it allocates 32-bit network Control Protocol/ addresses to nodes. The host requires a procedure for passing IP packets to the desired application. This procedure is filled by the TCP/IP. Internet Protocol) Test chart A specially designed copier original, with printed gauges used to assess many aspects of copy quality.

10 March 2004 21 Appendix 1 Glossary of Terms

Thermal Head The thermal head is the central component of the thermal printer. A thermal head consists of a row of heating elements. If a heating element is turned on, it will heat up. The heat from the element will make a dot on thermosensitive printer paper. Thermal Paper Thermosensitive printer paper. This is the paper used for white-board printers and thermal fax machines. A thermistor is a thermally sensitive . It is a heat-sensitive , which indicates changes in temperature by varying its electrical resistance. Thermoswitch An electrical control device used for overheat protection in office machines. Toner The “ink” of an electrostatic copier that forms the actual image on finished copies. It is made from resin and a solid lubricant combined with carbon or a colored pigment. In dual-component development systems it is bound to carrier particles by a triboelectric charge, creating two-component developer. See Triboelectric Charge. Toner Density Sensor The toner density sensor (or TD sensor) measures the concentration of toner in the (TD Sensor) developer. Toner End Sensor Part of a copier’s development system. The toner end sensor monitors the level of toner in the toner supply. When the sensor detects a predetermined “low-toner” condition, it signals the control system, which then a corresponding indicator on the machine’s operation panel. It usually detects two different toner levels: “Toner Near End” (low) and “Toner End” (too low to continue operation). Toner Overflow Sensor Part of a copier’s cleaning system. This sensor monitors the level of toner in the used toner storage tank. When the sensor detects a predetermined used toner tank full condition, it signals the control system, which then lights a corresponding indicator on the operation panel of the machine.

10 March 2004 22 Appendix 1 Glossary of Terms

Toner Shield Glass A piece of ordinary glass used in copiers as a “window” in the exposure slit; allows light to reach the photoconductor, but keeps toner from contaminating the optical system. Toner Supply System A combination of electronic and mechanical components that monitor the density of toner and add toner to the development unit whenever the density falls too low. Toner, Dual See Dual Component Toner. Component Toner, Magnetic See Magnetic Monocomponent Toner. monocomponent Toner, Non-magnetic See Non-magnetic Monocomponent Toner. monocomponent Torque limiter clutch In concept, torque limiter clutches transmit rotation to a drive component (usually a roller, pulley, or gear mounted on a rotating shaft). As long as the resistance to rotation is less than the torque (twisting force) limitation of the clutch, the roller turns with the shaft. If the resistance exceeds the torque limitation, the roller stops turning. It slips and in fact, may turn in the opposite direction if sufficient counter force is applied. Transfer That step in the copy process in which toner, held by the latent image on the photoconductor, is transferred to a blank sheet of paper, thereby creating a copy.

10 March 2004 23 Appendix 1 Glossary of Terms

Transfer and A corona unit used immediately after development. The T/S corona unit creates two Separation (T/S) coronas. The first, the transfer corona, is an electrical field that pulls the developed toner image away from the latent image on the photoconductor, transferring it to a Corona Unit sheet of paper. The second corona, the separation corona, is an electrical field that releases the paper, together with the developed toner image, from the photoconductor. Transport The primary job of a copier’s paper feed system: moving sheets of paper from the supply, through the machine, and out into the exit tray; accomplished with a variety of rubber belts and rollers. Trapping Layer The surface layer of a photoconductor. It receives and traps an electrostatic charge on the surface as long as the photoconductor is in darkness. Tray Heater Paper in a copier's paper tray tends to curl as it picks up moisture from the air. Some machines, especially higher speed models, have heaters in the paper trays to prevent such curling. Trellis Code Modulation TCM uses QAM, but part of the data signal is encoded, using trellis coding, for error (TCM) correction purposes. Triboelectric Charge A type of static charge that builds up when certain materials are rubbed together. Triboelectric charges attract toner to carrier in a two-component developer system. Two-component The most popular developer formulation; uses tiny, metallic carrier beads to deliver Developer much smaller toner particles to the photoconductor during the development process. Under-toning A condition that occurs when a copier’s toner supply system is delivering too little toner to the development unit; can lead to carrier abrasion, which may damage the photoconductor and shorten the useful life of the carrier particles.

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V Sensor A reflective photosensor similar to the ID sensor that indirectly measures drum potential. Used before the development of the potential sensor system, it can be found in earlier models using process control. Acts like two zener diodes connected back to back.

VB or VBB Development bias. VD (Dark Potential) The drum potential in black image areas after exposure. Standard VD is the potential measured after exposing a black pattern. VD Pattern A standard black pattern used for reference. VG or VGRID Charge corona grid potential. VH (Halftone Potential) A standard halftone drum potential. This value is used for laser power adjustment in the process control system of some digital products. Video Processing The processing that is applied to image data after the machine scans the document. Both analog and digital video processing steps may be applied to the image data. VL (Light Potential) The drum potential in white image areas after exposure. Standard VL is the potential measured after exposing a white pattern. VL Pattern A standard white pattern used for reference. On some machines the VL pattern is actually a light gray tone rather than pure white. VLAMP Exposure lamp voltage. VO (Original Potential) The drum potential after the drum is charged.

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Voice Message This converts recorded voice messages from analog (audio) to digital for storage in the memory. It also retrieves the message from memory to send it out over the telephone line. VR (Residual Voltage) The drum potential after the drum has been exposed by the erase lamp. VREF, VTREF A targeted control reference for the TD sensor. When VTD becomes too low, toner is added to the developer to bring VTD back to the VREF value. VSG The ID sensor output when checking the erased drum surface. VSP The ID sensor output when checking the ID sensor pattern image. VTD, VT, or VOUT The output voltage of the TD sensor. Xenon Flash Lamp The xenon flash lamps used in office machines are basically the same as the flash lamps used in photography only much larger. Xenon Lamp A xenon lamp is a xenon-filled glass tube with terminals at each end. When a voltage is applied across the lamp terminals, the xenon gas ionizes and current flows through the gas, which emits light. The terminals do not have to be preheated, unlike in fluorescent lamps. Fluorescent xenon lamps also utilize a phosphor coating on the inside wall of the lamp to generate light. Xerography The indirect electrostatic copying system which is the basis of all modern plain paper copiers; patented in 1939 by Chester Carlson, Xerography comes from the Greek words for “dry writing”. Zener Diode A diode connected in reverse to a normal diode and is designed to work in excess of the breakdown voltage.

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