Introduction
Optometer allow the precise and sensitive measurement of certain parameters of optical radiation. In dependence of the used detector and his calibration several different application ranges can be distinguished.
- Radiometry
- Photometry
- Colormetry
- Fiber Optic
All described detectors are based on semiconductor sensors (photodiodes) and are therefore suitable for extreme low power applications down to the pW level. To perform measurements with highest possible accuracy it is very important to operate the detectors in the linear response range. The upper limit of the optical power which can be measured directly is 1 mW. Using suitable, well selected and calibrated filters and attenuators it is possible to shift the measurement range to higher power levels.
In order to measure divergent sources like LED’s, laser diodes or optical fibers without collimating optics the detectors can be operated together with integrating spheres of 38 or 127 mm diameter. In dependence of the dimension of the entrance aperture we can reach attenuation factors of 1:6000.
The calibration of the detectors depends on the measurement task. In combination with filters and cosine diffusors or lenses it is possible to measure photometric parameters as well as optical power or phot current.
The calibration factors and the complete curve are stored in an EPROM inside the display unit. It is possible to store curves from several detector heads on one chip.
To operate the detectors three different display units are offered. You can chose between two laboratory units (single or dual channel) and one handheld meter with RS232 interface.
