they got the incorrect information. All sensors are analog. It all depends how the signal is processed.
Many users of cameras with CCD sensors are asking about the advantages of the latest CMOS sensors, particularly if they have been using CCD-based cameras. The two sensor technologies, a comparison of the new CMOS sensors and existing CCD sensors, and tips for when it makes sense to select a new camera with CMOS sensors are provided are provided here.
Charge coupled device (CCD) and complementary metal oxide semiconductor (CMOS) image sensors are currently on the market. Their task is to transform light (photons) into electrical signals (electrons). This information is transmitted by both sensor types using different methods, and the design of each is also fundamentally different.
In CCD sensors, the charges of the light-sensitive pixels are shifted and converted into signals. The charges of the pixels, which are created by exposure to a semiconductor, are transported to a central A/D converter with the support of many very small shifting operations (vertical and horizontal shift registers), similar to that of a “bucket chain.” The transfer of the charges is forced with the support of electrical fields, which are created by electrodes in the sensors.
In the CMOS sensors, a capacitor as a charge storage is put in parallel to each individual pixel. This capacitor is charged with the exposure of each pixel by its photoelectric current. The voltage created in the capacitor is proportional to the brightness and the exposure time. In contrast to CCDs, the electrons captured in the capacitors by the exposure of the sensor to light are not shifted to a single output amplifier, but are transformed into a measurable voltage directly at the source by means of each pixel’s own associated electronic circuit. This voltage can then be made available to the analog signal processor.
By using additional electronic circuits per pixel, each pixel can be addressed without the charge having to be shifted, as with CCDs. This results in the image information being able to be read much more quickly than with CCD sensors, and artifacts due to overexposure such as blooming and smearing occur far less frequently or not at all. The disadvantage of a CMOS is that the additional space required for each pixel’s electronic circuit is not provided as a light-sensitive area. The portion of the light-sensitive area on the sensor surface (defined by the fill factor) is then smaller than that of the CCD sensor. Theoretically, for this reason, fewer photons for the image information of a CMOS can be collected (not as sensitive). There are methods, however, for lessening this disadvantage by using digital manipulation.
So, CCD sensors needs a external A/D (analog to digital) converter and CMOS sensors needs signal processing done in analog internally. True video cameras are digital including their DSP (Digital Signal Processor) There is no such thing as a "analog camera". One way or another, they all end up digital internally.