Charge-coupled devices, or CCDs, are frequently used as camera sensor in microscope systems. These devices work by capturing the photons that are reflected off of an object and converting them into an image.
Even when a CCD is not being exposed to any light, dark current signals are being generated and create unwanted noise in an image. This noise is largely temperature-dependent, increasing as a CCD gets warmer. In order to combat this, CCDs that are used for highly-sensitive imaging are cooled, using various methods, to reduce the amount of noise. For example, the BZ Series Fluorescence Microscope utilises a Peltier-cooled CCD that reduces the temperature of the camera to 25 °C (45 °F) below the ambient temperature.