Infrared LED Drive & Receive mode

Receive mode
An infrared transmitting and receiving has two ways, one is direct style, the second is reflective. The direct type refers to the light-emitting tube and the receiving tube ends are relatively placed in emission and controlled object,and keep one’s distance;
Reflection type refers to the light-emitting tube and receiving tube tied together, usually receiving tube always no light, when infrared lighting of emitting diodes encounter a reflection the reflected Infrared LED was working,
Drive mode
The infrared transmitting to control the controlled device corresponding,the control of transmission power and control distance is proportional. In order to increase the control distance of infrared light, infrared light emitting diode is working on the pulse condition, because the pulse of light (light modulation) the effective transmission distance and peak current pulse is proportional, just try to improve the peak Ip, can increase the transmitting distance of infrared light. Improved Ip method, is to reduce the pulse duty ratio, namely the compressed pulse width of T, some color TV infrared remote control device, the infrared emitting tube work pulse duty ratio of about 1/3-1/4; some electrical appliances infrared remote control, the duty ratio is 1/10. Reducing the pulse duty transmitting distance empty ratio can also make the small power infrared emitting diode increases greatly. Common infrared light emitting diode, the power is divided into small power (1mW-10mW), power (20mW-50mW) and high power (above 50mW-100mW) three categories.To make the infrared light emitting diode produces a modulated light, only in the drive pipe pulse voltage with a certain frequency.When the infrared light-emitting diodes emit infrared to control the controlled device, has a corresponding infrared light and electric conversion element, such as an infrared receiver diode, phototransistor and so on. Practical infrared transmitter and receiver already paired two tubes.
Transmit beam current characteristics
General intensity of visible light-emitting diode light output unit as luminosity, such as infrared light-emitting diodes rather than the visible size of its output light energy, without visible light such as infrared light emitting diode of the output light energy unit as Watt(launch a bunch of Fe). The significance of the transmitted beam can move the amount of light emission energy in a unit of time. Emission beams of infrared light emitting diode generally also with the current ratio cause to be different. At the same time, the emission beam was also affected by the degree of Zhou Weiwen effect, the temperature drops, but enhance the emission beam; temperature rise, decreased (forward current has a fixed value), but because of heat loss and therefore, element temperature will increase the shape, so luminous efficiency will be affected and reduce.