Silicon avalanche photodiodes are used in the wavelength range between 250 nm and 1100 nm. The avalanche effect of these photodiodes makes them well suited for the detection of extremely weak light intensities.
Si-APD are suitable for the spectral range from 255 nm to 1100 nm.
Since the foundation of Laser Components Detector Group Inc. in 2004 we have built a product range comprising high quality APDs as well as low cost versions. The active area ranges from diameters of 230 µm to 3.0 mm. APDs with even larger areas (5 mm, 10 mm, and 16 mm) are manufactured by our partner Luna Innovations Incorporated.
Depending on type and specifications APDs are used for rangefinding, speed measurements, laser radar, security scanners, spectroscopy, fluorescence measurement as well as test and measurements systems in industrial, military, and medical markets. The avalanche effect is most effective whenever there is not much light available.
The APDs are available in different TO-housings with certain options such as lens cap, integrated filter, with TEC, SMD housing, or just on ceramic submount. In addition to a wide range of standard products our strength clearly is in customer specific developments.
All APDs in a TO-46 housing are available fibre coupled on an optional basis.
We gladly assist you with choosing the optimal APD for your application.
The SAE series features an epitaxial structure and is available as red enhanced (i.e. optimized for visible wavelengths) or NIR enhanced (i.e. optimized for NIR wavelengths) version. These APDs are inexpensive and feature a very large gain and dynamic range.
Low cost APDs in a miniature SMD packages. Responsitivity is optimized for 850 nm and 905 nm rangefinders. Optional, the SAHA series is also available with 905 nm bandpass filter.
The SAR series is based on a reach-through structure with a high sensitivity across the entire spectral range from 400 nm to 1100 nm. At the same time, rise and fall times are extremely fast (typically 450 ps). These APDs feature extremely low noise low dark current. In this series, lightpipe versions are available that have an optical fibre integrated into the cap; this fibre guides the light directly to the chip.
Specifically selected APDs (SARP series) can also be used for photon counting in Geiger mode (VR > VBR), where a single photon triggers an avalanche impulse of approximately 108 charge carriers. This APD is particularly suited for spectroscopy, fluorescence measurement, medical technology, and high end LIDAR applications.
One of the most common applications of Si-APDs is rangefinding systems based on the time-of-flight method (LIDAR). In the time-of-flight method, a 905 nm pulsed laser diode emits a laser pulse that reflects off an object and is focussed through an optic onto an APD chip. In order to achieve an optimal signal-to-noise ratio, an external band-pass filter that blocks the surrounding light has to be mounted in front of the APD or the optic. In the new SARF series, this filter comes already integrated into the TO housing.