Focal Plane Arrays & Multiplexing

NEP has developed a method to manufacture two-dimensional focal plane arrays of PbS and PbSe. These arrays are currently 64 x 64 elements with 65% coverage and pixel sizes of .005" x .005". In the near future we intend to expand this to 128 x 128 with pixel sizes in the area of .002". NEP has also developed the multiplexing to access the pixels and display the data from each pixel. This array works in the DC mode so no chopping is required and the image can be displayed on a standard 486 PC.

There are four basic approaches to using this new technology. The output protocols could be as follows:

• Analog Data Stream - The data is clocked out at a rate set by a clock line (internal or user supplied).
• RS-232 - The analog signal is digitized and converted to an RS-232 signal. The data can be sent over a standard link to a computer display.
• Computer and Camera System - Three small computer cards are used to acquire data not only from the infrared array, but also from a black and white camera. The two images are mixed and the video signal created can be displayed on a computer screen or converted to a standard NTSC signal for display on a TV.
• IR Camera, Stand Alone.

A PC based data acquisition system with software is in development. This system will allow limited manipulation of the multiplexed array signals and display of the data. Future embodiments will allow for computer control of various multiplexor parameters such as the clock and frame rate.

New England Photoconductor Corp. arrays are designed to operate in the 1-3 and 1-5 micron regions. Applications include, but are not limited to, spectroscopy, fire detection, process control, hydrogen fire detection, passive monitoring, alarm systems, and night vision. Please contact NEP for more details on our multiplexed array line.

New England Photoconductor Corp., 253 Mansfield Ave., P.O. Box M, Norton, MA 02766-0927. Tel: 508-285-5561; Fax: 508-285-6480.