High Reliability Cooled Hgcdte Fpa Long Range Surveillance Thermal Camera

      High Reliability Cooled HgCdTe FPA Long Range Surveillance Thermal Camera 

1 Introduction

1.1 Principle

The common camera is an equipment of visible imaging. Its image-forming principle is based on the difference between reflect and reflectance on the target surface. But the infrared thermal camera is different totally, it utilized the thermal contrast difference between targets and surrounding environmental conditions to forming the thermal radiation energy density images, we call it as "thermal imaging". As same as light wave and radio wave, the infrared radiation is a kind of electromagnetic wave. The wave band diagram refers to Figure 1.

Figure 1 Infrared wave band diagram

Because the human vision is not sensitive to infrared light, the thermal camera have to transform the infrared light to visible light and change the infrared image to visible image. As shown Figure 2, the function of transformer consists of 2 steps. Firstly, through the infrared thermal detector to transform the thermal radiations into electrical signals, which amplitude can reflect the strength of thermal radiation; Secondly, to display the electrical signals on monitor and get the visible infrared thermal image.

Figure 2 Principle of infrared imaging

JH640-800 long range surveillance thermal camera utilizes third generation HgCdTe 640x512 MWIR focal plane arrays (FPA) detector. The detector transform the target thermal radiations to electrical signals, after the process of a detailed analysis of electrical signals on image processing circuit boards, detector output analog and digital video signals together; the host PC control the thermal camera via RS232 communication interface. The basic principle diagram refers to Figure 3.

Figure 3 Principle of thermal camera

1.2 Features

JH640-800 long range surveillance thermal camera  is a matured and high reliability product which developed by our company independently. To ensure the thermal camera can totally meet the strict standard, we choose high-quality material and adopt top-ranking manufacture technology. Now the thermal camera has widely applied in the fields of aerospace, border & coast defense and city safety surveillance. This high-tech cooled infrared thermal camera is desperate needed in all-weather target detection, recognition and pre-warning system.

The thermal camera has advantages of small size, high sensitivity, easy to control, long surveillance range, continuous zoom (focal length is 80~800mm, the complete focusing movement time is not more than 6s), all weather operations, and good integration. It can be used as a single machine for monitoring, also can be integrated in the electro-optical pod used as forward looking infrared (FLIR) component.