Color Imaging in Machine Vision: How to Choose the Right Camera for Your Application
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Optical Coating Capabilities
6/7/2021 Optical Coating Capabilities | Optical Filter Coatings | Andover ISO 9001 AS 9100 ITAR Toll Free (US): +1 (888) 8939992 International: +01 (603) 893 6888 LOGIN CHECKOUT Search CONTROL THE LIGHT, SEE YOUR WORLD Standard & Custom Optical Filters and Coatings Home / Optical Filters & Assemblies | Coating Capabilities | Andover / Optical Coating Capabilities | Optical Filter Coatings | Andover OPTICAL COATING CAPABILITIES What is an Optical Filter Coating? An optical coating is one or more thin layers of material deposited on an optical component such as a lens or mirror, which alters the way in which the optic reflects and transmits light. One type of optical coating is an antireflection coating, which reduces unwanted reflections from surfaces, and is commonly used on spectacle and photographic lenses. Another type is the highreflector coating which can be used to produce mirrors that reflect greater than 99.99% of the light which falls on them. More complex optical coatings exhibit high reflection over some range of wavelengths, and antireflection over another range, allowing the production of dichroic thinfilm optical filters. Technologies Andover has a variety of optical coating technologies at its disposal, providing customers with solutions tailored to their specific applications. Technologies include: Magnetron Sputtering IonAssisted EBeam deposition Resistance Evaporation Hybrid Technologies We can design and manufacture coatings to meet your most demanding requirements. Range of Wavelengths from 193nm to 14 microns, on a wide variety of substrate materials including BK7, filter glass, borosilicate glass, Silicon, Germanium, Sapphire, Fused Silica, Calcium Fluoride, Zinc Selenide, Zinc Sulfide, and more. All Andover chambers are internally custombuilt, computercontrolled, and use the latest deposition techniques. -
Multispectral Imaging for Medical and Industrial Machine Vision Systems
1 | Tech Guide: Multispectral imaging for medical and industrial machine vision systems Tech Guide: Multispectral Imaging Multispectral imaging for medical and industrial machine vision systems 2 | Tech Guide: Multispectral imaging for medical and industrial machine vision systems Table of contents Introduction Chapter 1: What is multispectral imaging? Chapter 2: Multispectral imaging applications Chapter 3: Multispectral camera technologies Chapter 4: Key considerations when selecting camera technology for multispectral imaging Chapter 5: Hyperspectral and the future of multispectral imaging 3 | Tech Guide: Multispectral imaging for medical and industrial machine vision systems Introduction Just as machine vision systems have evolved from traditional monochrome cameras to many systems that now utilize full color imaging information, there has also been an evolution from systems that only captured broadband images in the visible spectrum, to those that can utilize targeted spectral bands in both visible and non- visible spectral regions to perform more sophisticated inspection and analysis. The color output of the cameras used in the machine vision industry today is largely based on Bayer-pattern or trilinear sensor technology. But imaging is moving well beyond conventional color where standard RGB is not enough to carry out inspection tasks. Some applications demand unconventional RGB wavelength bands while others demand a combination of visible and non-visible wavelengths. Others require exclusively non-visible wavelengths such as UV, NIR or SWIR, with no wavebands in the visible spectrum. Complex metrology and imaging applications are beginning to demand higher numbers of spectral channels or possibilities to select application-specific spectral filtering at high inspection throughputs. With the traditional machine vision industry merging with intricate measurement technologies, consistent, reliable, high-fidelity color and multispectral imaging are playing key roles in industrial quality control. -
Reflectance in Thin Films
TECHNICAL PAPER Reflectance in Thin Films Abstract Reflectance (R) is the fraction of incident light reflected from a surface and is an intrinsic optical property of thin films. It is essential in determining color, transparency and polarization characteristics of the film. Total internal reflectance is also important in devices such as optical waveguides. Reflectance depends on the energy band structure and associated plasma frequency of charge carriers. As a result, high reflection spectral regions are different for metals, semiconductors and insulators. Basic relations that determine reflectance will be presented and related to refractive index, extinction coefficient, color and transparency of these three classes of thin film materials. Reflectance of thin films also depends on thickness and surface quality. In addition to spectral dependence, the color associated with reflectance can also be described by Tristimulus values and Chromaticity diagrams. Antireflection and high reflection multilayer thin film coatings will also be addressed. Introduction The reflectivity or reflectance (R), of a surface is an intrinsic optical property of a surface. In many optical, electrooptic, telecommunications, solar concentrator and architectural applications, reflectance must either be controlled (reduced or enhanced), or the color of the object changed (e.g., given a “gold” color). For example, heat mirrors are used to reflect infrared wavelengths to reduce heat loss or ingress through windows. Infrared reflectance must be maximized while keeping visible light transmission through the window high. Multilayer low-e and solar control coatings are used to achieve this performance but must be applied to low cost plastic films and glazings. Combined with absorption, reflectance determines color and intensity (or energy) of reflected light. -
Light and Color
Chapter 9 LIGHT AND COLOR What Is Color? Color is a human phenomenon. To the physicist, the only difference be- tween light with a wavelength of 400 nanometers and that of 700 nm is Different wavelengths wavelength and amount of energy. However a normal human eye will see cause the eye to see another very significant difference: The shorter wavelength light will different colors. cause the eye to see blue-violet and the longer, deep red. Thus color is the response of the normal eye to certain wavelengths of light. It is nec- essary to include the qualifier “normal” because some eyes have abnor- malities which makes it impossible for them to distinguish between certain colors, red and green, for example. Note that “color” is something that happens in the human seeing ap- Only light itself paratus—when the eye perceives certain wavelengths of light. There is causes sensations of no mention of paint, pigment, ink, colored cloth or anything except light color. itself. Clear understanding of this point is vital to the forthcoming discus- sion. Colorants by themselves cannot produce sensations of color. If the proper light waves are not present, colorants are helpless to produce a sensation of color. Thus color resides in the eye, actually in the retina- optic-nerve-brain combination which teams up to provide our color sen- Color vision is sations. How this system works has been a matter of study for many years complex and not and recent investigations, many of them based on the availability of new completely brain scanning machines, have made important discoveries. -
United States Patent (19) 11 Patent Number: 6,072,635 Hashizume Et Al
US006072635A United States Patent (19) 11 Patent Number: 6,072,635 Hashizume et al. (45) Date of Patent: Jun. 6, 2000 54) DICHROIC PRISM AND PROJECTION FOREIGN PATENT DOCUMENTS DISPLAY APPARATUS 7-294.845 11/1995 Japan. 75 Inventors: Toshiaki Hashizume, Okaya; Akitaka Primary Examiner Ricky Mack Yajima, Tatsuno-machi, both of Japan Attorney, Agent, or Firm-Oliff & Berridge, PLC 73 Assignee: Seiko Epson Corporation, Tokyo, 57 ABSTRACT Japan The invention provides a dichroic prism capable of reducing displacements of projection pixels of colors caused by 21 Appl. No.: 09/112,132 chromatic aberration of magnification. A dichroic prism is formed in the shape of a quadrangular prism as a whole by 22 Filed: Jul. 9, 1998 joining four rectangular prisms together. A red reflecting 30 Foreign Application Priority Data dichroic plane and a blue reflecting dichroic plane intersect to form Substantially an X shape along junction Surfaces of Jul. 15, 1997 JP Japan .................................... 9-1900OS the prisms. The red reflecting dichroic plane is convex shaped by partly changing the thickness of an adhesive layer 51 Int. Cl." ............................ G02B 27/12: G02B 27/14 for connecting the rectangular prisms together. Accordingly, 52 U.S. Cl. ............................................. 359/640; 359/634 Since a red beam can be guided to a projection optical System 58 Field of Search ..................................... 359/634, 637, while being enlarged, it is possible to reduce a projection 359/640 image of the red beam to be projected onto a projection plane Via the projection optical System. This makes it 56) References Cited possible to reduce relative displacements of projection pix U.S. -
Backstage Lighting Terminology
Break-out: Adapter consisting of multiple receptacles (FM) wired to a single multipin (M) connector; may be a box or a cable assembly. Synonym: Break-out Box, Fan-out Burn Out: Failed lamp or color media that is burned through Channel: Specific control parameter encompassing single or multiple device attributes (lighting dimmers, audio signals, etc.) controlled as a unit Lighting and Electrics Terminology (A-Le) Channel Hookup: Paperwork designating the connection of Adapter: Electrical accessory that transitions between dimmer circuits to channels of control dissimilar connectors; may be a molded unit, box or cable assembly Circuit: Path for electricity to flow from the source, through a conductor, to a device(s) Amperes: Unit of measure for the quantity of electricity flowing in a conductor. Synonym: A, Amp, Current Circuit Breaker: Mechanical/Electrical device that is designed to automatically open (trip) if the current exceeds the rated Automated Luminaire: Lighting instrument with attributes level protecting the circuit; may be operated manually that are remotely controlled. Synonym: Automated Fixture, Synonym: Breaker, CB, OCPD, Overcurrent Protective Device Automated Light, Computerized Light, Intelligent Light, Motorized Light, Mover, Moving Light Color Extender: Top hat with color media holder. Synonym: Gel Extender Backlight: A lighting source that is behind the talent or subject from the viewers perspective. Synonym: Backs, Back Color Frame: Metal or heat resistant device that holds the Wash, Bx, Hair Light, Rim Light color media in front of a luminaire. Synonym: Gel Frame Balcony Rail: Lighting position mounted in front of or on the Color Media: Translucent material used to color light face of the balcony. -
Characterization of Color Cross-Talk of CCD Detectors and Its Influence in Multispectral Quantitative Phase Imaging
Characterization of color cross-talk of CCD detectors and its influence in multispectral quantitative phase imaging 1,2,3 1 1,2 1 AZEEM AHMAD , ANAND KUMAR , VISHESH DUBEY , ANKIT BUTOLA , 2 1,4 BALPREET SINGH AHLUWALIA , DALIP SINGH MEHTA 1Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India 2Department of Physics and Technology, UiT The Arctic University of Norway, Tromsø 9037, Norway [email protected] [email protected] Abstract: Multi-spectral quantitative phase imaging (QPI) is an emerging imaging modality for wavelength dependent studies of several biological and industrial specimens. Simultaneous multi-spectral QPI is generally performed with color CCD cameras. However, color CCD cameras are suffered from the color crosstalk issue, which needed to be explored. Here, we present a new approach for accurately measuring the color crosstalk of 2D area detectors, without needing prior information about camera specifications. Color crosstalk of two different cameras commonly used in QPI, single chip CCD (1-CCD) and three chip CCD (3-CCD), is systematically studied and compared using compact interference microscopy. The influence of color crosstalk on the fringe width and the visibility of the monochromatic constituents corresponding to three color channels of white light interferogram are studied both through simulations and experiments. It is observed that presence of color crosstalk changes the fringe width and visibility over the imaging field of view. This leads to an unwanted non-uniform background error in the multi-spectral phase imaging of the specimens. It is demonstrated that the color crosstalk of the detector is the key limiting factor for phase measurement accuracy of simultaneous multi-spectral QPI systems. -
Comparative Analysis of Color Architectures for Image Sensors
Comparative analysis of color architectures for image sensors Peter B. Catrysse*a, Brian A. Wande11', Abbas El Gamala aDept of Electrical Engineering, Stanford University, CA 94305, USA bDept ofPsychology, Stanford University, CA 94305,USA ABSTRACT We have developed a software simulator to create physical models of a scene, compute camera responses, render the camera images and to measure the perceptual color errors (CIELAB) between the scene and rendered images. The simulator can be used to measure color reproduction errors and analyze the contributions of different sources to the error. We compare three color architectures for digital cameras: (a) a sensor array containing three interleaved color mosaics, (b) an architecture using dichroic prisms to create three spatially separated copies of the image, (c) a single sensor array coupled with a time-varying color filter measuring three images sequentially in time. Here, we analyze the color accuracy of several exposure control methods applied to these architectures. The first exposure control algorithm (traditional) simply stops image acquisition when one channel reaches saturation. In a second scheme, we determine the optimal exposure time for each color channel separately, resulting in a longer total exposure time. In a third scheme we restrict the total exposure duration to that of the first scheme, but we preserve the optimum ratio between color channels. Simulator analyses measure the color reproduction quality of these different exposure control methods as a function of illumination taking into account photon and sensor noise, quantization and color conversion errors. Keywords: color, digital camera, image quality, CMOS image sensors 1. INTRODUCTION The use of CMOS sensors in digital cameras has created new opportunities for developing digital camera architectures. -
Can I Bring Dreams to Life with Quality & Versatility?
Can I bring dreams to life with quality & versatility? They've been dreaming about the wedding day for months. Positioning the green CCD out of line PROFESSIONAL FLUORITE LENS (pixel shift) sharpens image reproduction Canon has always led the way in optical Every detail has been planned. It goes perfectly. Bride and even if your subject moves. A new Super development. The first to equip a cam- Pixel Shift (horizontal + vertical) achieves corder with a fluorite lens – a lens that groom look radiant and the guests enjoy themselves. wider dynamic range for movies, reducing provides the quality of 35mm and vertical smear and gives 1.7 mega-pixel broadcast TV. The XM2 has a Professional You can bring back those special moments in a top-quality high resolution photos. L-Series fluorite lens. Combined with 20x optical zoom and 100x digital zoom, video recording. plus an optical image stabiliser, you can be sure of superior images. SUPERB QUALITY INSPIRATIONAL VERSATILITY The Canon XM2 Digital Camcorder No two video shoots are alike. What's combines the best of all worlds. Its happening, where it's happening, move- advanced technology delivers unri- ment, colour – it all demands a certain valled image quality in its class, while it amount of fine-tuning to capture the is still easy to operate. That makes it an special moments you want. The XM2 ideal choice for both serious camcorder features adjustments and enhancements enthusiasts, professional video- for sound and picture for your personal graphers and filmmakers. Whether creativity. Plus a LCD screen for easy you're regularly providing broadcast viewing. -
ELEC 7450 - Digital Image Processing Image Acquisition
I indirect imaging techniques, e.g., MRI (Fourier), CT (Backprojection) I physical quantities other than intensities are measured I computation leads to 2-D map displayed as intensity Image acquisition Digital images are acquired by I direct digital acquisition (digital still/video cameras), or I scanning material acquired as analog signals (slides, photographs, etc.). I In both cases, the digital sensing element is one of the following: Line array Area array Single sensor Stanley J. Reeves ELEC 7450 - Digital Image Processing Image acquisition Digital images are acquired by I direct digital acquisition (digital still/video cameras), or I scanning material acquired as analog signals (slides, photographs, etc.). I In both cases, the digital sensing element is one of the following: Line array Area array Single sensor I indirect imaging techniques, e.g., MRI (Fourier), CT (Backprojection) I physical quantities other than intensities are measured I computation leads to 2-D map displayed as intensity Stanley J. Reeves ELEC 7450 - Digital Image Processing Single sensor acquisition Stanley J. Reeves ELEC 7450 - Digital Image Processing Linear array acquisition Stanley J. Reeves ELEC 7450 - Digital Image Processing Two types of quantization: I spatial: limited number of pixels I gray-level: limited number of bits to represent intensity at a pixel Array sensor acquisition I Irradiance incident at each photo-site is integrated over time I Resulting array of intensities is moved out of sensor array and into a buffer I Quantized intensities are stored as a grayscale image Stanley J. Reeves ELEC 7450 - Digital Image Processing Array sensor acquisition I Irradiance incident at each photo-site is integrated over time I Resulting array of intensities is moved out of sensor array and into a buffer I Quantized Two types of quantization: intensities are stored as a I spatial: limited number of pixels grayscale image I gray-level: limited number of bits to represent intensity at a pixel Stanley J. -
Camera Sensors
Welcome Processing Digital Camera Images Camera Sensors Michael Thomas Overview Many image sensors: Infrared, gamma ray, x-rays etc. Focus on sensors for visible light (slightly into infrared and uv light) Michael Thomas, TU Berlin, 2010 Processing Digital Camera Images, WS 2010/2011, Alexa/Eitz 2 The beginnings First Video camera tube sensors in the 1930s Cathode Ray Tube (CRT) sensor Vidicon and Plumbicon for TV-Broadcasting in the 1950s – 1980s Vidicon sensors on Galileo-spacecraft to Jupiter in 1980s Michael Thomas, TU Berlin, 2010 Processing Digital Camera Images, WS 2010/2011, Alexa/Eitz 3 The Photoelectric-Effect How to convert light to electric charge? Inner photoelectric-effect at a photodiode: Photon excites electron creating a free electron and a hole The hole moves towards the anode, the electron towards the cathode Now we have our charge! Michael Thomas, TU Berlin, 2010 Processing Digital Camera Images, WS 2010/2011, Alexa/Eitz 4 Charge-Coupled Device (CCD) Integrated circuit Array of connected capacitors (Shift register) Charge of capacitor is transfered to neighbour capacitor At the end of chain, charge is converted into voltage by charge amplifier Transfer stepped by Clock-Signal Serial charge processing Michael Thomas, TU Berlin, 2010 Processing Digital Camera Images, WS 2010/2011, Alexa/Eitz 5 CCD-Sensor Each capacitor is coupled with a photodiode All capacitors are charged parallelly Charges are transferred serially Michael Thomas, TU Berlin, 2010 Processing Digital Camera Images, WS 2010/2011, Alexa/Eitz -
How Digital Cameras Capture Light
1 Open Your Shutters How Digital Cameras Capture Light Avery CirincioneLynch Eighth Grade Project Paper Hilltown Cooperative Charter School June 2014 2 Cover image courtesy of tumblr.com How Can I Develop This: Introduction Imagine you are walking into a dark room; at first you can't see anything, but as your pupils begin to dilate, you can start to see the details and colors of the room. Now imagine you are holding a film camera in a field of flowers on a sunny day; you focus on a beautiful flower and snap a picture. Once you develop it, it comes out just how you wanted it to so you hang it on your wall. Lastly, imagine you are standing over that same flower, but, this time after snapping the photograph, instead of having to developing it, you can just download it to a computer and print it out. All three of these scenarios are examples of capturing light. Our eyes use an optic nerve in the back of the eye that converts the image it senses into a set of electric signals and transmits it to the brain (Wikipedia, Eye). Film cameras use film; once the image is projected through the lens and on to the film, a chemical reaction occurs recording the light. Digital cameras use electronic sensors in the back of the camera to capture the light. Currently, there are two main types of sensors used for digital photography: the chargecoupled device (CCD) and complementary metaloxide semiconductor (CMOS) sensors. Both of these methods convert the intensity of the light at each pixel into binary form, so the picture can be displayed and saved as a digital file (Wikipedia, Image Sensor).