Final answer:
The light-sensitive chip in modern optical telescopes is the Charge-Coupled Device (CCD), which detects photons and converts them into electronic signals that can be counted and processed for imaging in fields like astronomy and biomedical imaging.
Step-by-step explanation:
The light-sensitive chip used in modern optical telescopes is called a Charge-Coupled Device (CCD). CCDs are semiconductor chips that detect photons of radiation. When these photons strike the CCD, they generate a stream of charged particles (electrons) which are then stored and subsequently counted at the end of the exposure time. Each area where radiation is detected and counted is known as a pixel, with modern CCDs capable of measuring photons in millions of pixels—referred to as megapixels, or MPs. This technology is analogous to that which is used in devices like digital cameras and cell phones, enabling the electronic processing and storage of images.
Photon detectors like CCDs rely on the particle-like properties of photons interacting with a sensitive area to record images. CCDs have multiple applications beyond astronomy, including biomedical imaging systems where there is ongoing research focused on enhancing the efficiency of photon reception.