afocal system मीनिंग इन हिंदी

This type of system is called an " afocal system ", since it produces no net convergence or divergence of the beam.
Afocal systems are used in laser optics, for instance as beam expanders, Infrared and forward looking infrared systems, camera zoom lenses and telescopic lens attachments such as teleside converters, and photography setups combining cameras and telescopes ( Afocal photography ).