Oct 23, 2017: Prüftechnik Schneider & Koch offers the measurement of ultra-bright LEDs in its LaserVision-LED AOI and function test system. LEDs used in the automotive sector are today far beyond 500lm per individual LED and deliver more than 1000lm in modular design.
The LaserVision LED test system does a complete testing, including AOI testing, of a PCB up to 1500mm long. It also tests LEDs with regard to light parameters. The testing of ultra-bright LEDs is difficult due to their brightness. The new AOI system has an optical attenuation and an additional camera to solve this problem. This does not change the LEDs’ colour characteristics, and hence, the unit can be defined according to the maximum brightness of the LEDs to be tested.
With the test system LaserVision LED, LED units can be tested in the production line to 100% in the cycle time. This includes the AOI inspection as well as the complete electrical test, and as a result of the combination also the optical measurements of the operated LEDs. Therefore, a 100% inspection in the
LED assemblies including the components can be checked automatically for placement, solder joints, shorts, polarities etc.. In addition, photometric tests are possible. The unique combination of photometric measurement and camera inspection is used here under requirements of inline production. LED lights can be tested completely as final products and / or in different production levels. The test is done on the level of single LED.
The electric contacting during inline mode is carried out by a contacting unit that is powered parallel by servomotors. This unit can be constructed to work from either the bottom or the top. A special holding-down device was developed.
Areas of application
The combination of photometric measurement, camera inspection and electric test is implemented in various stages:
Automatic calibration by means of a photometric measurement
- light intensity
- color temperature
- light density
LED control in line speed by means of a camera (AOI)
- color angle
Possibility of additional testing by means of a camera (AOI)
- examination for presence and polarity of LED and SMD components
- solder joint examination on LED and SMD components
- short-circuit test (solder bridges)
- electric functional test