OPTOELEKTRONIKA

The Golay cell is a type of opto-acoustic detector mainly used for infrared spectroscopy. It consists of a gas-filled enclosure with aninfrared absorbing material and a flexible diaphragm or membrane. When infrared radiation is absorbed, it heats the gas, causing it to expand. The resulting increase in pressure deforms the membrane. Light reflected off the membrane is detected by a photodiode, and motion of the membrane produces a change in the signal on the photodiode. The concept was originally described by Marcel J. E. Golay,^[2] after whom it came to be named.

The Golay cell has high sensitivity and a flat response over a very broad range of frequencies. The response time is modest, of order 10 ms. The detector performance is degraded in the presence of mechanical vibrations.

Golay Cell is one of the most efficient detecting devices. It has excellent sensitivity at room temperature and flat optical response over a wide wavelength range.

Golay detectors are manufactured in-house and calibrated individually. Delivery includes a detector head and a power supply unit. A mount for the filters can be supplied as an option.

Various THz optical components such as low pass filters, polyethylene polarizers as well as windows, lenses, and beamsplitters from HRFZ-Si and TPX can be supplied as a useful complement for THz applications. 

For transforming an analog signal of Golay cell to a digital signal we can offer  hardware-software complex. It is served for detecting, processing, and analyzing optoacousticaldetector signals. The complex consists of  a specialized software and an electronic unit connecting Golay detector with personal computer through USB interface.

Application:                                                                                  

Monitoring and control of MIR and THz radiation.

Technical specification:

Diameter of entrance cone, mm: 11.0 Diameter of entrance window, mm: 6.0 Material of entrance window: High-Density Polyethylene (HDPE) Optimal operating wavelength range, μm: 15 ÷ 8000 Recommended detected power, W, up to: 1 x 10-5 Optimum modulation frequency, Hz: 15 ± 5 Noise-equivalent power @ 20Hz: typical, W/Hz1/2 minimum, W/Hz1/2 1.4 x 10-10  0.8 x 10-10 Optical responsivity @ 20Hz: typical, V/W maximum, V/W 1 x 105  1.5 x 105 Response rate: typical, ms minimum, ms 30  25 Detectivity (D*) at entrance cone aperture:  typical, cm x Hz1/2/W maximum, cm 7.0 x 109  11.0 x 109 Ambient operating pressure range, mm Hg 760 ÷ 10-3 Operational and storage temperature range, °C 5 ÷ 40 Humidity, % 45 ÷ 80 Vibration avoid vibrations at 1 ÷ 100 Hz Rated voltage, VAC 100/115 ± 10%,  220/230 ± 10% Line frequency, Hz 50 ÷ 60 Overall dimensions, L x W x H, mm3 126 x 45 x 87 Weight, kg 0.8

sources : 

http://en.wikipedia.org/wiki/Golay_cell