The following Hong Jin Xiaobian will introduce you to the principle of infrared emission tube:

   The general infrared LED tube has a shape similar to that of a general visible LED, but emits infrared light. The tube pressure is generally reduced by about 1.4v, and the operating current is generally less than 20mA.

In order to adapt to different operating voltages, a series of finite current resistors are often found in the loop. When infrared rays are emitted to control the corresponding controlled device, the distance controlled is proportional to the transmitted power. In order to increase the infrared control distance, the infrared light-emitting diode operates in a pulse state, because the effective transmission distance of the pulsating light (modulated light) is proportional to the peak current of the pulse, and it is only necessary to increase the peak value Ip to increase the emission distance of the infrared light. The method of improving Ip is to reduce the pulse duty ratio, that is, the width T of the compression pulse. For some color TV infrared remote controllers, the working pulse duty ratio of the infrared light-emitting tube is about 1/3-1/4; some electrical products are infrared. The remote control has a duty cycle of 1/10. Reducing the pulse duty cycle also greatly increases the emission distance of the low power infrared light emitting diode. Ordinary infrared light-emitting diodes are divided into three categories: low power (1mW-10mW), medium power (20mW-50mW) and high power (50mW-100mW or more). In order for the infrared light emitting diode to generate modulated light, it is only necessary to apply a pulse voltage of a certain frequency to the driving tube. When the infrared light emitting diode emits infrared light to control the controlled device, the controlled device has a corresponding infrared light-electrical conversion component, such as an infrared receiving diode, a phototransistor, and the like. In practice, there are already diodes for infrared emission and reception pairing.