Glossary - alphabet order - "U"
UV & IR-cut filter coating
It is a multi-layer coating for filtering out both ultraviolet light (light with wavelength of 400 nm or below) and infra-red light (light with wavelength of 650 nm or above). A CCD or CMOS device is sensitive to both ultraviolet and infra-red light. Ultraviolet light casts a bluish tinge on images. This filter coating remove this coloring.
Reference: IR-cut filter coating
This refers to a crystal device's resistance to the ultrasonic vibrations that are applied for cleaning in the assembly process. Crystal devices require more care during cleaning than other electronic devices, due to the hard, brittle nature of the quartz crystal itself and to the (one-sided) support structure for the crystal chip in the package. In particular, special care is required for products that contain a tuning fork crystal chip.