The Model 1508 eight element detector array is available in two configurations: 1508 VM (voltage mode) and 1508 CM (current mode). Both devices come standard in a hermetically sealed 18 pin packages. Elements are photo-lithographically defined onto specially processed lithium tantalate crystals. Detectors windows are AR coated for enhanced transmissivity with selections available in the 2 to 15 micron range.
PERFORMANCE
Description
Servo Corporation's Model 1508VM pyroelectric infrared detector array uses a specially processed and prepared Lithium Tantalate crystal for the detection element coupled to integral low noise hybridized JFET impedance buffering voltage mode preamplifiers.
Servo now utilizes this material's superior properties in a standard linear array. The performance advantages of this material are its large pyroelectric current output, high temperature stability and Curie temperature. This produces arrays with high sensitivity and consistent and stable performance even at higher operating temperatures.
The integral hybridized preamplifier buffers the very high impedance levels of the detection elements with minimal noise production. The low impedance output signal can thus be easily interfaced to standard electronics circuits. The output voltage is proportional to the current produced in the pyroelectric element and its capacitive reactance. The buffer circuits are hermetically sealed in a metal package with the detector, thus problems associated with using this type of electronic circuit are minimized.
The basic 1508VM package in its eight element configuration can be easily modified to a total of 16 elements. In addition, different element geometries and spacings can be supplied. For higher frequency operation the detector's time constant can be adjusted.
The device operates from a single power supply and requires a very low operating current. The standard window supplied is an 8-12 micron filter. Other windows or elements are available. Contact Servo's applications engineers for details.
Specifications (Typical)
Actual Element Size: 0.5mm x 0.5mm, ±.05 mm
Element Gap: 0.1 mm
Responsivity (10 Hz): 5,000 volts/watt
Crosstalk: 8% @ 10 Hz N.E.P.(500K, 10 Hz, I Hz BW): 3.0 x 10-10 W/Hz 1/2
D * (5OOK, 10 Hz, I Hz BW): 1.66 x 108cmHz1/2/W
Operating Voltage: Maximum 18 volts DC, Minimum 3 volts DC, Typical 9 volts DC
Operating Current: (1OOK Source Resistance): Maximum 1.6 ma., Minimum .04 ma., Typical .10 ma.
Output Impedance: (1OOK Source Resistance) 20K ohms
Operating Temperature: -40 deg to +85 deg. C
Spectral Response (STD): 8 to 12 microns
For further information please call 516 938
9700 ext 277or email 
us.