New Line of Lead Salt Detectors from Cal Sensors Block Interfering Radiation to Optimize Industry-leading Measurement Performance

CalSensorsSCD-SiDetectorSIZEDCal Sensors announces the launch of a new line of single channel detectors (SCD) that block unwanted radiation below 1.2 microns.  Exploiting the innate transmission bandwidth of Silicon, the new SCD-Si detectors are packaged with anti-reflection Silicon windows to block undesirable energy in the UV and visible spectrums. Thus these detectors focus on the infrared spectrum, minimizing the effects of unwanted radiation that can interfere with test results and reduce measured dynamic range. Optimizing performance in the 1.2 to 5.5 microns infrared spectrum, the SCD-Si detectors combine the superior sensitivity and fast response-times of lead salt detectors with the band-limiting attributes of Silicon to provide excellent quality, long life and high performance detection.

Design & Applications

Anti-reflective (A/R) coated Silicon is readily available, robust and can be designed to optimize the transmission in the near to mid-IR spectrum.  It is an ideal material for filtering the radiation that hits the detector in the 1.2 to 5.5 microns operational bandwidth. The synergistic attributes: superior sensitivity, fast response times, and band-limited radiation combine to produce a line of detectors that are ideal for a wide range of applications including:

  • medical diagnostics
  • environmental gas analysis
  • fire detection
  • process and quality control
  • thermal imaging or hot-spot detection

The SCD-Si detectors are available in a variety of configurations. Users can select PbS or PbSe detector material, 2×2 mm or 3×3 mm active area sizes and ambient or cooled configurations.

Long-Pass Filtering and Enhanced Field-of-View

The SCD-Si line of detectors is the result of numerous customer requests to block shorter wavelength “unwanted” radiation (long-pass filtering). Cal Sensors has provided detectors with this attribute for many industry leaders in the above mentioned applications.

Packaging enhancements have also been addressed with the new SCD-Si detectors.  The line´s ambient detectors (AP and BXP models) double the field of view (FOV) as compared to existing lines of Cal Sensors detectors.  Maximizing FOV is particularly important for gas or fire detection applications that monitor a large area such as an oil refinery or manufacturing plant.  The AP-x5Si and BXP-x5Si series of detectors feature a short cap (0.13 inches tall with 0.25 inches aperture) to optimize the FOV.  The cooled detectors (ATx and BXTx series) require a standard cap height (0.233 inches tall) to support the additional space required by the thrermo-electric cooler (TEC).

Industry-Leading Sensitivity

Lead salt (PbS and PbSe) detectors offer superior sensitivity and measurement response speed over the near to mid-IR spectrum.  Lead Selenide (PbSe) covers the 1.0 to 5.5 µm infrared region offering a typical detectivity (D*) of 1.5E10 Jones (cm(Hz)1/2/W).  Lead Sulfide (PbS) provides 1.0 to 3 µm coverage with a typical D* of 1E11 Jones. Cooling the detectors with an integrated TEC can improve the D* by up to a factor of 3.  The new SCD-Si line will offer the same performance with a cut-on wavelength of 1.2 microns. PbS and PbSe lead salt detectors are more cost-effective than more complex technologies such as InSb, InAs and HgCdTe and provide 10 times or greater sensitivity than low cost detectors like pyroelectric, bolometric or thermopile options.

The new SCD-Si detectors address frequent industry requests with a cost-effective alternative to Cal Sensors’ existing detector lines.  Custom solutions are still supported when needed to address unique application requirements.

Cal Sensors presented the new SCD-Si lead salt detectors at booth 3620 at the 2014 Pittcon Conference & Expo held March 2-6, 2014 at McCormick Place in Chicago. Lead time for SCD-Si detectors varies between 12 to 16 weeks depending on complexity.