Single-element detector diffraction effects

Improvement of lateral spatial resolution In the mapping method using a single-element detector, reduction of spatial resolution can be caused by diffraction due to the presence of a masking aperture which is needed to define the area from which the infrared spectrum should be measured. As already pointed out, no aperture is needed for a measurement with an array detector as each pixel of the array detector is responsible for interrogating a different small area of a sample, diffraction effects are lessened. 

---