VIGO System offers an advanced infrared detection module that incorporates an infrared photodetector, heat dissipation systems, optics, signal processing electronics, and other components in a standard package.
A combination such as this makes detectors less sensitive to electromagnetic interferences, electrostatic discharges, overbias, and other environmental exposures. This combination also provides other benefits, like output signal standardization, enhanced high-frequency (HF) performance, cost reduction, and miniaturization.
The detection modules available from VIGO System are equipped with an infrared detector. These modules are optimized for uncooled temperatures or for temperatures that can be realized with Peltier-cooler operation in the spectral range between 2 and 12 μm.
Numerous circuit designs have also been designed to improve the performance of the modules in a wide range of applications.
When an object emits IR radiation, it is focused on the active area of an IR detector to create photoelectric signals that are subsequently detected by the front-end electronics (FEE).
The front-end electronics circuitry is commonly used to:
- Offer the best possible conditions to facilitate the operation of IR detectors (to obtain a quick response, a wide dynamic range, and high sensitivity. This is generally realized with improved constant voltage bias and the current mode of the photoelectric signal readout.
- Intensify the signal within the needed frequency band. This could be achieved by making sure that the preamplifier noise makes only a minimal contribution to the resulting noise of the detection module.
- Shield detector elements from overbias
Besides the front-end electronics, detection modules may feature supplementary electronic blocks for signal conditioning, like analog-digital converters (ADC), thermoelectric cooler controllers, filters, gain blocks, and other components.
Several applications need high-time resolution or, at the most, high frequency-bandwidth optical detection. For such kinds of applications, VIGO System has designed ultra-high-speed detection module series.
An exclusive design should be applied, both in terms of mechanics and electronics. The module was specifically developed to support the propagation of high-speed signals, placing the detector to the enclosure as close as possible to input circuits and a printed circuit board (PCB) board.
During the manufacturing process, the circuit should be further adjusted with a particular detector. The system also features a DC monitor. This DC-coupled signal is directly taken from the first-stage preamplifier. Users should consider the 1 VDC offset at the DC monitor output.
This output could be used to:
- Quantify the mean optical power by the detector
- Monitor the dark current of the photodetector
UHSM is one of the fastest, long-wavelength, commercially available infrared detection modules.
Two models of ultra-high-speed detection modules are available. The two models are optimized to operate in the spectral range from 3 to 12 µm:
- Optically immersed—with frequency bandwidth ranging from 300 to more than 700 MHz
- Without immersion microlens—with frequency bandwidth ranging from 300 to more than 1.3 GHz.
These types of modules are mainly used in heterodyne detection, dual-comb spectroscopy, object scanners, LIDARs, characterization of pulsed laser sources, telemetry, free-space communication, and time-resolved fluorescence spectroscopy systems.
Source: VIGO System
||Optimal wavelength λopt, µm
||Optical area Ao, mm×mm
||Detectivity D* (λopt), cm·Hz1/2/W
||Output voltage responsivity Rv (λopt, RL=50 Ω), V/W
|| -3 dB Bandwidth
||300 Hz to ≥ 1.3 GHz
||300 Hz to ≥ 700 MHz