╗╩╣┌ÎŃ▓╩Thermoelectric Cooling Solutions

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Uncooled Matrix Photodetectors

A range of uncooled matrix photodetectors consists of two classes of devices: uncooled microbolometer matrices and charge coupled devices.

The microbolometer matrix (often named as Focal Plane Array - FPA) is a two-dimensional matrix of tiny thermal sensors elements. The principle of operation of each element is based on the change of electrical resistance with temperature. Temperature changes by absorption of light. A high sensitivity is achieved by state-of-art methods of manufacturing very small items with low thermal inertia and heat capacity. The technology is based on techniques of microelectronic devices (lithography, vacuum deposition, etc.) and elements of modern technology of MEMs.

Charge coupled devices (matrices of photodetectors based on charge-coupled device elements) are relatively young multi-element photodetector devices (matrices and linear arrays). The principle of operation is based on generating (and holding) the charges due to the absorption of light at the point of absorption and transport of the charge and his reading.

A significant advantage of such matrix photodetectors unlike photodetectors based on quantum photoelectric effect is that for them the cooling is not necessary in principle, at least, significant cooling. They operate well under normal room conditions. For example, in a variety of everyday digital imaging applications.

However, for high-precision applications the temperature control is required. These photodetectors have temperature dependence of key performance parameters, such as thermal noise, a dark current. In addition, because of notable size matrices with large integration (dimensions 10 x 10 ...15 x 15 mm2 and more), there is a need for temperature stabilization and temperature uniformity along the sensitive surface.

Such tasks are performed using thermoelectric cooling – typically single-stage TECs.

RMT produces TECs for uncooled matrix Photodetectors.

Thetre are large single-stage TECs in the series 1MC06 and 1MC10. The maximal size of the TECs are un to 18Đů18 đ╝đ╝2 and more.

To increase the homogeneity of temperature across the surface the TEC are made with use of aluminum nitride ceramics having high thermal conductivity.

If you also want to cool below room temperature, RMT has developed and produces special two-stage modules with increased cold area 2MDX06, 2MDX10. With use of three stage TECs of the series 3MDC10 temperature of matrix devices can be decreased much more below 0°C.

The company RMT also advises complete solutions – TECs mounted onto standard and customized packages suitable for matrix devices use.

All the products are manufactured in whole conformity with the standard of reliability Telcordia GR468 Core. The modules of RMT are fully compliant with RoHS đŞ REACH requirements.

To select a suitable solution and the optimal TEC for an application, the supporting Online TEC Assistance is available at RMT’s website. For detailed modeling and calculations the company RMT provides our customers by free software TEC Cad or iTECPad.

And contact RMT for advice and assistance.