Advantages of Image Sensor | disadvantages of Image Sensor
This page covers advantages and disadvantages of Image Sensors (CCD and CMOS) and their basics. It mentions benefits or advantages of Image Sensor and drawbacks or disadvantages of Image Sensor.
What is Image Sensor?
It consists of two-dimensional array of thousands of discrete pixels. The amount of light on these pixels generates free electrons. The quantum of charge depends on intensity of incident photons.
Both CCD and CMOS depend upon photoelectric effect in order to create electrical signal from the incident light photons. Both uses different technologies in order to capture digital image. Both the sensors differ in conversion of charge into voltage as well as readout of the chip.
The figure-1 above depicts CCD image sensor.
The figure-2 above depicts CMOS image sensor. Unlike CCD sensor, in CMOS sensor, each pixel has its own charge to voltage converter, amplifier and pixel select switch. Refer CCD vs CMOS image sensors >> for more information.
Benefits or advantages of Image Sensor
Following are the benefits or advantages of Image Sensor:
➨CCD image sensor offers high sensitivity in poor light conditions.
➨CCD image sensor possesses high speed imaging capabilities including better daytime imaging performance.
➨CCD sensor has reduced likelihood of damage while viewing in bright conditions.
➨The data transmitted from two different LED transmitters (mounted on vehicle rear LED array and trafc light) can be captured easily and distinguished simultaneously by using image sensor.
➨Background noise sources such as sunlight, ambient light and digital signage can be discarded by separating the pixels associated with such noise sources. Hence Image Sensor provides secure, interference free and reliable communications in outdoor conditions.
Drawbacks or disadvantages of Image Sensor
Following are the drawbacks or disadvantages of Image Sensor:
➨CCD image sensor offers high power consumption due to requirement of active cooling of CCD.
➨In CMOS sensor, uniformity and imade quality is poor as each pixel does its own conversion.
➨The frame rate of commonly used image sensor is 30 frame per second. This is not adequate to achieve high data rate communication.
➨Image sensor works by detecting optical light which is LOS. Hence the performance of link degrades when link is blocked by any object which prevents light penetration such as walls, buildings, thick gas and thick fog.
➨CCD image sensor has higher power consumption and consecutively shorter battery life.