Two Color Sandwich Detectors


Dual Sandwich Detectors or Two Color Detectors are mostly employed for remote temperature measurements. The temperature is measured by taking the ratio of radiation intensities of two adjacent wavelengths and comparing them with the standard black body radiation curves. The advantages of optical remote measurement have definitely made these devices the perfect match for this type of measurements. They are independent of emissivity and unaffected by contaminants in the field of view or moving targets. In addition, measurements of targets out of the direct line of sights and the ability to function from outside RF / EMI interference or vacuum areas are possible. They also have the advantages of overcoming obstructed target views, blockages from sight tubes, channels or screens, atmospheric smoke, steam, or dust, dirty windows as well as targets smaller than field of view and / or moving within the field of view. These detectors can also be used in applications where wide wavelength range of detection is needed.

OSI Optoelectronics offers three types of dual sandwich detectors. The Silicon-Silicon sandwich, in which one silicon photodiode is placed on top of the other, with the photons of shorter wavelengths absorbed in the top silicon and the photons of longer wavelengths penetrating deeper, absorbed by the bottom photodiode. For applications requiring a wider range of wavelength beyond 1.1 ┬Ám, an InGaAs photodiode replaces the bottom photodiode. The silicon-InGaAs version is also available with a two stage thermo-electric cooler for more accurate measurements by stabilizing the temperature of the InGaAs detector. All devices are designed for photovoltaic operation (no bias), however, they may be biased if needed, to the maximum reverse voltage specified. They are ideal for coupling to an operational amplifier in the current mode. For further details refer to the "Photodiode Characteristics" section of this catalog.

Product Applications

  • Flame Temperature Sensing
  • Spectrophotometer
  • Dual-Wavelength Detection
  • IR Thermometers for Heat Treating, Induction Heating, and other metal parts processing

Product Features

  • Compact
  • Hermetically Sealed
  • Low Noise
  • Wide Wavelength Range
  • Remote Measurements
  • w/ TEC

Non-Cooled

Model Number Detector Element Active Area Spectral Range Peak Wavelength Responsivity Shunt Resistance Capacitance Rise TIme Dat Peak Reverse Voltage Package Click Image to Zoom
PIN-DSIn Si (top) 2.54 mm² 400 - 1100 nm 950 nm 0.55 A/W at 870nm 150 MΩ 450 pF 4 µs 1.2 e -+13 cm√Hz/W (870nm) 5 V 17 / TO-5 No image found for (PIN-DSIn)
PIN-DSIn InGaAs 1.50 mm² 1000 - 1800 nm 1300 nm 0.6 A/W 1 MΩ 300 pF 4 µs 8.4 e +11 cm√Hz/W 2 V 17 / TO-5 No image found for (PIN-DSIn)
PIN-DSS Si (top) 2.54 mm² 400 - 1100 nm 950 nm 0.45 A/W 500 MΩ 70 pF 10 µs 1.7 e +13 cm√Hz/W 5 V 17 / TO-5 No image found for (PIN-DSS)
PIN-DSS Si 2.54 mm² 950 1100 nm 1060 nm 0.12 A/W 500 MΩ 70 pF 150 µs 4.7 e +12 cm√Hz/W 5 V 17 / TO-5 No image found for (PIN-DSS)

Two Stage Thermoelectrically Cooled

Model Number Detector Element Active Area Spectral Range Peak Wavelength Responsivity Shunt Resistance Capacitance Rise Time Dat Peak Reverse Voltage Package Click Image to Zoom
PIN-DSIN-TEC Si (top) 2.54 mm² --- 950 nm 0.55 A/W at 870nm --- 450 pF 4 µs 1.2 e +13 cm√Hz/W (870nm) --- 24 / TO-8 No image found for (PIN-DSIN-TEC)
PIN-DSIN-TEC InGaAs 1.50 mm² 1000 - 1800 nm 1300 nm 0.6 A/W 1 MΩ 300 pF 4 µs 8.4 e +11 cm√Hz/W 2 V 24 / TO-8 No image found for (PIN-DSIN-TEC)
§ @ 870 nm
‡ Thermo-Electric Cooler and Thermistor Specifications are specified in the tables below.