26-04-2011, 09:28 AM
Presented by :-
Ganesh Prasad
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What is Opto-electronics .:-
It the branch of electronics dealing with devices that generate, transform, transmit, or sense optical, infrared, or ultraviolet radiation, as solar cells and lasers.
Component of opto-electronics. :-
What is Opto-electronics Sensor.:-
An opto-electronic sensor is a device that is capable of producing an electrical signal that is proportional to the amount of light incident on the active area of the device.
Integrated optoelectronic sensors are designed to recognize fundamental stimuli such as patterns, images, motion and intensity and colour.
Basic Types of Integrated Opto-electronic Sensors. :-
Opto-electronics sensor system. :-
All of these types of integrated optoelectronic sensors can be used in automotive applications.
In an automotive environment, this can be especially important because mechanical sensors typically are less robust. Non-contact optoelectronic sensors are generally more cost-effective because they have a much longer ‘lifetime’ and are able to achieve a significantly higher level of resolution, which in turn increases the accuracy of the ‘sensed’ or ‘measured’ results.
In the automobile, sensors are being used under the hood and in the cabin as well as being scattered around the outside of the cabin and engine compartment. However, integrated optoelectronic solutions are used almost entirely in the cabin, primarily in the safety, comfort and convenience features.
Some of the basic type opto-electronics sensor systems used. :-
Ambient light sensor in-cabin backlight control.
Rain sensor systems.
Electro-chromatic mirrors system.
Sun load sensors system.
Daylight/twilight and exterior lighting control system.
Occupancy detection sensors system.
Lift gates and van door safety sensors system.
Keypad Backlighting system.
Ambient light sensor in-cabin backlight control. :-
ambient light sensors automatically adjust the backlighting of the instrument panel and various other displays in the vehicle according to the varying available – or ambient – light conditions. In addition to providing a pleasant-looking display, ambient light sensors also help reduce power dissipation and maximise the life of the backlighting system.
Rain sensor systems. :-
optoelectronic sensors are used in a reflective mode in rain sensor systems to detect the presence of water on the windshield so that the windshield wipers can be controlled automatically.
Electro-chromatic mirrors system. :-
Optoelectronic sensors are used in chromatic mirrors to sense the approaching lights of a following vehicle and automatically dim rearview mirrors.
Sun load sensors system. :-
sun load sensors incorporate optoelectronic sensors to detect the position and intensity of sunlight and automatically control air conditioning and heating levels.
Daylight/twilight and exterior lighting control system. :-
optoelectronic sensors are used to detect various environmental light levels so that headlights can be turned on or off automatically.
Occupancy detection sensors system. :-
Occupancy detection sensors incorporate optoelectronic sensors to detect the presence or absence of human body forms and adjust the deployment of air bags accordingly. In addition, optoelectronic sensors can be used to automatically adjust both seat and belt positions.
Keypad Backlighting system. :-
Most phones from a leading US mobile phone manufacturer features an ambient light sensor. It is used to control the keypad backlight. When there is enough ambient light to see the keypad, the backlight remains off until any of the keys are pressed.
Why opto-electronics sensor system used. :-
The sensors used in an automotive environment must be reliable.
produce exactingly accurate results.
require little maintenance.
help reduce overall system cost and extend the life of the system or sub-system unit.
Integrated optoelectronic sensors are non-contact sensors. that is, they are able to perform their sensing or measurement functions without the need for physical contact with other parts of the system or sub-system
Advantages. :-
reducing the number of required components.
improving the reliability of the system or subsystem.
improving the styling, aesthetics and ergonomics of the overall vehicle through better utilisation of the available space.
improving the manufacturability of the vehicle by reducing the number of sensors that need to be positioned during production.
Disadvantages. :-
One disadvantage of optoelectronic input devices is that they are often not giving any direct feedback.
