IREM Technology

IREM-I

The IREM-I (also IREM1) introduced three essential technologies for the world’s first infrared emission microscope: (a) high sensitivity HgCdTe infrared FPAs (Focal Plane Array) originally developed for NASA, (b) near-IR and thermal-IR Optics and (c) LN2 cryostats designed by Infrared Laboratories to maintain low temperatures. In addition, LN2 cooling of lenses, blocking filters and a cryo-stepper motor driven cooled filter wheel were also introduced.

HgCdTe FPA

The benefit of using the full bandwidth of the HgCdTe FPA is that thermal microscopy at 2.5 microns provides a useful way to detect and measure hot-spots caused by electrical shorts.

IREM-II PE

As transistors have grown smaller and less power hungry the IREM-II (also NG-IREM) was designed and developed by Infrared Laboratories as the next generation of IREM to view photoemission sites. In the IREM-II, InGaAs FPAs are cooled to 78 K.  Depending on the particular objectives in use, quantitative measurements show very large enhancements relative to the IREM-I.

Optics

1X and 25X

For the IREM-II optics, new optical materials and new AR coatings were used. As a result, the IREM-II 1x design provides a numerical aperture (NA) of 0.25 and a large working Distance (WD). The 25x objective uses the same optical materials and coatings to provide a NA of 0.50 and a 17 mm WD.  Measured performances of both custom designs show exceptional efficiency and resolution, compared with the standard spectral band of 1.07 to 1.55 microns.

Infrared LED

Illuminators are important components for microscopes, and infrared LEDs were first introduced in the IREM-II.

AIRIS

Software

Both IREMs are fully supported by AIRIS, our Advanced Infrared Emission Imaging Software. All of the various hardware operations are well integrated, and image processing functions are designed to optimize signal-to-noise along with real-time image conditioning such as precision flat-fielding and bad-pixel removal. The built in image processing is based on a number of key astronomical techniques and algorithms that enhance spatial resolution and localization. 

Thermal Emission Microscopy

For the next generation of thermal emission microscopy the HgCdTe FPA now operates faster. Unwanted blackbody emission is rejected by LN2 cooling of a special baffle and Lyot stop. In conjunction with a 2-position cooled optics slide a 3-position warm slide provides a large cooled set of lenses to increase the thermal signals.  Magnifications are 1x, 15x and 36x. Thermal mapping will employ a proprietary calibration procedure.