1 | Energy Efficiency and Renewable Energy eere.energy.gov 

# Television Set On Mode Automatic Brightness Control Testing: Effect of Infrared and Neutral Density Filters February 2013 Department of Energy Energy Efficiency and Renewable Energy2 

# Research Overview

• Based on DOE’s Round Robin Test Report 1 

## , DOE n oticed a variation in power consumption when testing automatic brightness control (ABC) TVs using the distance test s et -up c ompared the adjacent test set-up

• A possible cause could be Infrared (IR) light leading to more 

## rapid ABC sensor saturation

– DOE research indicated that some TVs may use higher quality ABC sensors that filter to visible light only, whereas other TVs may use sensors sensitive to IR light

– Halogen lamps emit light outside of the visible spectrum

1 Round Robin Test Report available in Docket #EERE- 2010 - BT - TP -0026 at regulations.gov.3 

# Testing Overview

• Lamp: 980 lumen PAR 30S halogen • T est set-up: Distance and Adjacent 2 

## • Measurement:

– Illuminance meter placed in front of the ABC sensor

– Measured light wavelength and spectral intensity

– Measurements made at 12, 35, 50 and 100 lux illuminance values

– Measurements made with Konica Minolta T- 10 Illuminance meter

2 Round Robin Test Report available in Docket #EERE- 2010 - BT - TP -0026 at regulations.gov.4 

# Spectral Analysis

• The area under each curve represents the amount of light emitted by the lamp at that illuminance value • The vertical line separates the visible and IR spectrums 0 50 100 150 200 250 300

350 450 550 650 750 850 950Spectral Intensity (μW/nm)

Wavelength (nm) Distance Test Set - up

100 lux 50 lux 35 lux 12 lux IR Spectrum (750-1000 nm)5 

# Spectral Analysis

• The area under each curve represents the amount of light emitted by the lamp at that illuminance value • The vertical line separates the visible and IR spectrums 0 50 100 150 200 250 300

350 450 550 650 750 850 950Spectral Intensity (μW/nm

Wavelength (nm) Adjacent Test Set - up

100 lux 50 lux 35 lux 12 lux IR Spectrum (750 - 1000 nm)6 

# IR to Visible Light Ratio

• The ratio of IR to visible light increased as the lamp decreased in illuminance Illuminance (lux) Ratio of IR to visible light Distance Adjacent 12 3.5 18 35 3.5 8.5 50 3.3 7.6 100 3.1 7.57 

# IR Filter Testing

• DOE conducted additional ABC on mode testing with an IR filter to determine the effects on illuminance • TVs selected based on saturation values of round robin 

## testing 3 

## to determine a range of effects

– TV 1 (lowest saturation value)

– TV 5 (highest saturation value) 

## • Stabilization – played IEC 62087 dynamic video clip for one hour prior to testing • Method

– Tested both Distance and Adjacent test set-ups

– Filter - Hoya 67 mm ultraviolet (UV) and IR blocking filter to ensure only visible light entered the ABC sensor
3 Round Robin Test Report available in Docket #EERE- 2010 - BT - TP -0026 at regulations.gov.8 

# IR Filter Testing

• IR filter placement

– All set-ups ensured no unfiltered light entered the ABC sensor



## • TVs tested at the following illuminance values

– 3, 10, 12, 35, 50, 75, 100, 300 lux 

## • All testing conducted in on mode Distance IR test set-up 1 Filter directly in front of the lamp Distance IR test set-up 2 Filter directly in front of the sensor Adjacent IR test set- up Filter at the end of the apparatus9 

# IR Filter Test Set- up Distance IR Test S et -up 1

Figure not to scale10 

# IR Filter Test Set- up Distance IR Test S et -up 2

Figure not to scale11 

# IR Filter Test Setup Adjacent IR Test S et -up

Figure not to scale12 

# IR Filter Results

Illuminance (lux) TV 1 – Distance IR Set- up On Mode Power Consumption (watts) % Difference Test set-up 1 Filter at lamp Test set-up 2

Filter at ABC sensor 3 71.6 71.7 0.22% 10 75.5 79.5 5.05% 12 81.6 81.7 0.16% 35 137.6 139.4 1.28% 50 153.7 153.8 0.07% 75 153.5 153.6 0.09% 100 153.3 153.4 0.08% 300 153.2 153.4 0.08%13 

# IR Filter Results

Illuminance (lux) TV 5 – Distance IR Set- up On Mode Power Consumption (watts) % Difference Test set-up 1 Filter at lamp Test set-up 2

Filter at ABC sensor 3 27.0 27.0 0.02% 10 30.9 31.6 2.13% 12 32.8 33.7 2.50% 35 39.3 39.0 0.84% 50 43.0 43.1 0.10% 75 61.2 59.1 3.59% 100 61.6 61.5 0.06% 300 71.5 71.5 0.09% Remaining analyses performed using data from Distance IR test set-up 214 

# TV 1 Results

Lines connecting data points used only for visual aid and do not indicate any trends or relationships between the data 60 80 100 120 140 160 180

0 50 100 150 200 250 300Power (watts)

Illuminance (Lux) TV 1

Distance test set-up Adjacent test set-up Distance IR test set-up 2 Adjacent IR test set-up15 

# TV 5 Results

Lines connecting data points used only for visual aid and do not indicate any trends or relationships between the data 0 10 20 30 40 50 60 70 80 90

0 50 100 150 200 250 300Power (watts)

Illuminance (Lux) TV 5

Distance test set-up Adjacent test set-up Distance IR test set-up Adjacent IR test set-up16 

# IR Filter Results

Illuminance (lux) % Reduction in Power

TV 1 % Reduction in Power TV 5 Distance* Adjacent** Distance* Adjacent** 10 37% 54% 32% 56% 12 38% 54% 33% 55% 35 12% 31% 42% 44% 50 2% 21% 41% 24% 75 2% 2% 20% 19% 100 2% 2% 19% 14% 300 2% 3% 7% 6% * Reduction in power measured when using Distance test set-up 2 compared to the Distance test set-up with no IR filter ** Reduction in power measured when using Adjacent test set-up compared to the Adjacent test set- up with no IR filter Note: Highlighted cells indicate illuminance values at which the TV is saturated 

## • On mode percent difference in power consumption with ABC enabled without an IR filter compared to with an IR filter17 

# ND Filter Testing

• In Working Draft 3 of CEA- 2037 -A, CEA proposed using 3 lux for one of the ABC testing illuminance values



## • CEA proposed two methods for achieving 3 lux

– Directly measure 3 lux using a high quality illuminance meter

– Measure 12 lux at the ABC sensor and then place 2 stop neutral density (ND) filter in front of the sensor, resulting in 3 lux18 

# ND Filter Testing

• DOE performed testing using both methods proposed by CEA

– Directly measure 3 lux using a high quality illuminance meter

– Measure 12 lux at the ABC sensor and then place 2 stop neutral 

### density (ND) filter in front of the sensor, resulting in 3 lux



## • Stabilization

– Played IEC 62087 dynamic video clip for one hour prior to testing



## • Testing performed

– On three TVs with ABC – TVs 1, 3, and 5 4



### – Using the Distance test set- up

– Without an IR filter 4 Round Robin Test Report available in Docket #EERE- 2010 - BT - TP -0026 at regulations.gov.19 

# ND Filter Test Set- up
• Without ND filter

– Illuminance set to 3 lux

– Measured directly using a Konica Minolta T- 10 illuminance meter • Accuracy of ± 2% ± 1 digit 

## • With ND filter

– Illuminance set to 12 lux, measured directly using a Konica Minolta T10 illuminance meter



### – A 67 mm Hoya Pro1 Digital ND4 filter was placed directly in front of the ABC sensor



## • Measured power consumption and compared results20 

# ND Filter Test Set- up

Figure not to scale 

## Test Set -up without ND Filter21 

# ND Filter Test Set- up

Test Set -up with ND Filter

Figure not to scale22 

# ND Filter Results

Test Set - up Power Consumption (watts) @ 3 lux

TV 1 TV 3 TV 5 No ND filter 71.6 65.0 34.1 With ND filter 71.6 64.8 30.9 Coefficient of Variation* 0.04% 0.23% 6.91%

* Coefficient of Variation (CV) is the ratio of the standard deviation to the mean of a given sample23 

# IR and ND Filter Testing DOE repeated its testing using an IR filter

• Hoya 67 mm UV and IR blocking filter placed directly in front 

## of ABC sensor • Without ND filter:

– Illuminance set to 3 lux measured with a Konica Minolta T- 10 illuminance meter 

## • With ND filter:

– Illuminance set to 12 lux measured with a Konica Minolta T- 10 illuminance meter

– Hoya Pro1 Digital ND4 Filter placed in series with the UV/IR blocking filter

– DOE tested this set-up twice – reversed the order of the filters to ensure this had no effect on power consumption24 

# IR and ND Filter Test Set-up 1

Figure not to scale 

## • Test set-up with filters placed at the ABC sensor • The ND filter is positioned closer to the lamp25 

# IR and ND Filter Test Set-up 2

Figure not to scale 

## • Test set-up with filters placed at the ABC sensor • The IR filter is positioned closer to the lamp26 

# IR and ND Filter Results

Test Set- up Power Consumption (watts)

TV 1 TV 3 TV 5 IR filter Only 71.6 64.9 27.0 IR/ND Set-up 1 ND filter closest to lamp 71.3 65.5 26.9 IR/ND Set-up 2 IR filter closest to lamp 71.7 64.9 27.1

CV 0.27% 0.58% 0.41%