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.
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.