The 80026 Mercury Cadmium Telluride (MCT) detector’s broad spectral response extends into the mid-IR region. This liquid nitrogen cooled detector measures signals approximately 100 times weaker and acquires data about 8 times faster than the Oriel^® 80008 room temperature DTGS detector. Liquid nitrogen holding time is eight hours. A two-stage, low noise amplifier is built into the housing and requires no user adjustments. An off-axis parabolic reflector is integrated into the design, rather than a focusing lens. IR refractive optics are expensive and have transmittance limitations. Using this type of reflector provides several advantages. Its gold coating enhances IR reflectance. The focal point is displaced from the mechanical axis, giving full access to the reflector focus area. There is no shadowing with the detector’s active area positioned at the focal point. A manually adjustable iris is included with the 80026. Its diameter range is from 0.8" to 1.4" (2 to 36 mm). The iris can act as a Jacquinot Stop. By decreasing the effective source size and reducing the spot size on the detector, the resolution increases. The iris uses standard Oriel 1.5-Inch Series male and female flanges, allowing it to be easily integrated into the FT-IR system, if desired.