This single element detector is effective in sensing wavelengths between 1000 nm and 5500 nm. Please note that it is available in various sensor area sizes and includes a dewar to hold liquid nitrogen for significantly lower dark current and improved signal to noise. The output is an analog signal available through a BNC connector at the back of the detector housing. Since the signal is analog, an optional 12-bit and 16-bit data acquisition system and software is available to digitize its output into a computer. A DC power supply for this detector (sold separately) is also required. This detector is designed for use with scanning monochromators to capture the intensity of one wavelength at a time. An optional mount allows it to mate to any Sciencetech scanning monochromators. Sciencetech can also provide an optional custom mount for mating to non-Sciencetech monochromators and spectrographs.
The output voltage is proportional to radiation incident on the active area as follows:
V_out = P_sig x R_λ x R_f
where P_sig is incident power in watts, R_λ is the photodiode responsivity in A/W at the wavelength of interest, and R_f is the amplifier transimpedence gain. This is DC coupled with high gain and extensive care should be taken in shielding the unit from any ambient light during operation. Exposure to room lights may cause amplifier saturation and can lead to failure of the unit.
Response Time
Liquid nitrogen cooled InSb detectors have very fast response times in the nanosecond range. However, modifications to the circuitry maybe required to obtained these speeds at the sacrifice of gain. Please consult with a Sciencetech Applications Specialist for details.
Technical Specifications

• Shunt Resistance: > 2 MΩ @ 77K
• Shunt Capacitance: 450 pF typical
• Responsivity @ 5.3 µm: 5 x 10⁵ / 10⁴ V/W @ amp out
• Dewar Hold Time: 8 hours minimum with liquid N₂
• Field of View: 60° nominal
• Amplifier: Dual-Gain Transimpedance
• Bandwidth: DC – 200 kHz
• Connections: BNC signal coaxial cable with 3 lead shielded power cable.
  Red = +V, Black = -V, White/Shield = ground
  Note: A DB9 connector is provided on units purchased with optional PS-1 Low Noise Power Supply