LABORATORIES OF AMERICA
Avoid TV Brightness Limits
Limits on TV brightness would be ineffective and counter to the goals of Energy Star LABORATORIES OF AMERICA Proposed luminance measurement
The home or standard mode Measured with the JEITA test luminance level shall not be signals (black, white, colorbar less than 80% of the & 3-bar) luminance level of the Measured in the middle of the manufacturer’s selectable screen mode with the highest Measured on axis luminance level.
2 LABORATORIES OF AMERICA Proposed measure would be ineffective
Dynamic Broadcast-Content Video Signal APL′
The brightness of the JEITA 600.0Black 75% CB 3 bar White signals (black, white, colorbar, 500.0
400.0
3-bar) does not correlate with Master 300.0 Test Video IEC power 200.0
100.0 Frequency ( Frames per 1% APL' bin ) 1% APL' per Frames ( Frequency
0.0 0 102030405060708090100 APL' ( % )
Static test signals can be Home Mode Retail Mode “gamed.” Brightness Brightness
APL’ (%) APL’ (%)
“gaming the system” 3 LABORATORIES OF AMERICA A correlated brightness measure is impractical
What about measuring the brightness of the IEC loop?
10 minutes Exactly corner to corner + =
Requires a dark environment Requires expensive test equipment Requires exact calibration
What about off-axis luminance?
Does not consider perceived brightness
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LABORATORIES OF AMERICA Different technologies – are very different!
PDP Efficacy LCD Efficacy 180 400 160 350 140 BL = -15 300 120 Color bar BL = -10 (green brightness/0.44) Cinema 250 100 BL = -5 Standard 80 200 BL = 0 Vivid 60 150 BL = +5
BL = +10 Brightness (cd/m2) 40
Brightness (cd/m2) 100 3 bar White BL = +15 20 50 0 0 0 100 200 300 400 0 50 100 150 200 Pow er (W) Pow er (W)
LCD brightness is naturally Power-limited Plasma TVs are linear with respect to the non-linear at high-brightness backlight power. settings.
* 37-inch, pre-3.0 LCD TV * 42-inch, pre-3.0 Plasma TV 5 LABORATORIES OF AMERICA We convert watts to light
TV Manufacturers are working hard to improve efficiency
Reduce TV Power consumption
Increase perceived brightness
TV technologies turn watts into light. More watts mean…
LCD: brighter peak levels
Plasma: brighter levels during mid/high APL conditions
6 LABORATORIES OF AMERICA Performance limits reward inefficiency
High efficiency panel Low efficiency panel
Retail mode Retail mode 25% more brightness Home mode 25% more brightness Home mode Very little additional power allotted Huge amounts of Eco mode Eco mode additional power allotted JEITA Brightness JEITA Brightness JEITA
IEC Power IEC Power
I can slow down an automobile by Installing a smaller engine -OR - Adding lead weights!
Energy Star should avoid performance limits
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LABORATORIES OF AMERICA Energy Star should be 100% IEC 62087 based
IEC 62087 should be the basis of all Energy Star measurements It cannot be “gamed” It correlates with real world power consumption It is technology neutral It rewards efficiency It requires no new test equipment
Dynamic Broadcast-Content Video Signal APL′ The measurement can be performed at 600.0 retail 500.0
The test loop has been internationally 400.0
Master vetted 300.0 Test Video
The test loop has been embraced by all 200.0
100.0 stakeholders bin ) 1% APL' per Frames ( Frequency
0.0 0 102030405060708090100 APL' ( % )
8 LABORATORIES OF AMERICA The current proposal is too restrictive
Home Mode Brightness vs. Power
Too much restriction limits power savings on all TVs Power
Shipped brightness Shipped “Sweet Spot”
No restriction risks a small number of overly dark TVs
Nobody knows exactly where the sweet spot is. (Allow the manufacturers to find it.) 9 LABORATORIES OF AMERICA Energy Star should reward efficiency
A ratio rewards inefficiency
With a ratio, an efficient TV gets a smaller additional allotment for retail than an inefficient TV
An “adder” rewards efficiency
All TVs of a given size would get the same allotment
10 LABORATORIES OF AMERICA Leave no “holes” in the measurement
If a TV fails to meet a home to retail relationship, what is it’s rated average
power consumption?
Currently, there are no measurement “holes” in Energy Star 3.0.
Tier 2 should also have no measurement “holes.”
11 LABORATORIES OF AMERICA Summary
The current proposal…
Does not correlate with IEC 62087 levels
Can be “gamed”
Is not technology neutral
Rewards inefficiency (performance limit; ratio)
Is too restrictive – takes away the “sweet spot”
Measuring IEC loop brightness is impractical
Adders reward efficiency; ratios don’t
Tier 2 should avoid measurement “holes”
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LABORATORIES OF AMERICA
Thank you!
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