MEASURING & TESTING BEAMER / PROJECTOR.

Manish Abraham & Reinhard Pollhamer

Table of Contents

Product Description. Technical Aspects. LCD Memory Effect. Humidity and Temperature. Cooling Fan Defect. Lamp Durability.

Product Description

Video projector Receives a video signal from TV-receiver,

PC, BluRay-Player, gaming console etc. Projects the pictures on a projection screen. Uses a lens system.

Product Description

Lens system of a LCD-Projector.

Technical Aspects

Light output measured in lumens. from 1500 lm for small rooms with low

ambient light up to over 4000 lm for big screens and/or no lighting control.

Resolution common resolutions are 800x600,

1024x768, 1280x720 and 1920x1080 pixels.

other formats have to be scaled.

Technical Aspects

Picture deformation when projector has a horizontal or vertical

offset to the projection screen. digital or analog correction.

Temperature and noise heat is produced by the lamp. fans are needed to protect from

overheating.

What could be tested?

LCD Memory Effect. Button durability. Remote control (distance, obstacles). Lamp durability (3000-6000h; On/Off). Humidity and temperature

differences. Defect of cooling fan. Light output (decreasing over lifespan).

What is to be tested?

LCD Memory Effect: places on the lense can get darker if they are exposed to bright pictures.

Lamp durability: lamp is designed for 5000 operating hours.

Humidity and Temperature: the projector should be resistant to inside as well as outside conditions.

Defect of cooling fan: overheating of critical components should be prevented.

LCD Memory Effect Test

To give an idea of different test parameters, I would like to show a presentation on different parameters and then show our test.

LCD Memory Effect

2 test pictures

Testing durations: 15 / 30 / 45 / 60 / 70 / 80 / 90 / 100 / 120 / 150 / 180 minutes

LCD Memory Effect

Results Check image quality of a pure black

respectively pure white image after each time period.

Protocol at which time and place/color the effect occured.

LAMP DURABILITY

The Lamp inside a Projector.

Lamp Durability

Lamp should endure 5000 hours of usage(>200 days).

Long time usage and many Power-On/Off procedures have a bad influence on durability.

To shorten the test time the projector is switched On/Off frequently. Randomized On/Off-signals or fixed values.

Humidity and Temperature

Intended temperature range for use between -5° C and +40° C

Intended humidity range for use between 20 and 90 %

Protocol sheet with intervals shorter intervals at critical temp. or humidity

levels

Test environment climate chamber

Humidity and Temperature

Humidity [%] Temperature [°C] Status

20 20 OK

40 20 OK

60 20 OK

70 20 OK

75 20 …

80 20 …

85 20 …

90 20 …

92 20 …

94 20 …

Cooling Fan Defect

System must shut down before overheating

Temperature sensors in the projector case

Cooling Fan Defect

1st task: find the critical temperature.

2nd task: configure the built-in temperature sensor.

3rd task: test if the system shuts down when the critical temperature is reached.

Questions ?????