Infrared transmitting tube is composed of infrared transmitting tube matrix luminous body
Infrared transmitting tube is composed of infrared transmitting tube matrix luminous body.
The infrared emission diode by infrared radiation of high efficiency materials (
Commonly used gallium arsenide GaAs)
Made of p-n junction, plus forward biased to the p-n junction injection current stimulate infrared light.
Spectral power distribution as the center wavelength of 830 ~ 950 nm, about 40 nm half peak bandwidth, it is a narrow distribution, for the common CCD camera can feel the scope of the black and white.
Its big advantage is that can be completely without red storm, (
Using 940 ~ 950 nm wavelength infrared tube)
Or only a faint red (
Red critical to have a visible red light)
And long service life.
The launch of the infrared transmitting tube power expressed in irradiance mu W/m2.
The launch of the infrared transmitting tube strength by mW/sr said.
In general, the infrared radiation intensity is proportional to the positive working current, but near the big forward current rating, the temperature of the device for current heat consumption to rise, make the light emitting power decrease.
Infrared transmitting tube current is too small, will affect the radiation power of the play, but the working current overshoot affects its life, and even make the infrared tubes burned.
Emission intensity and temperature also has a certain relationship: in the case of temperature rise, emission intensity will also decline.
Judgment method of infrared light-emitting diodes: step discriminant of infrared light-emitting diode pin positive and negative electrode polarity.
Infrared light emitting diode, there are two pins, usually long pin is positive, negative short pin.
Infrared light emitting diode is transparent, so the electrode is clearly visible inside the shell, internal wider than the larger one is negative electrode, and a narrow and small one for the positive.
The second step puts multimeter R x 1 k block, measuring positive and reverse resistance of infrared light-emitting diodes (leds), usually, the forward resistance should be around 30 k, reverse resistance to above 500 k, so the pipe can be normal use.
For reverse resistance is bigger, the better.
Infrared transmitting tube packaging materials of low hardness, the high temperature resistant performance is even worse, to avoid damage, the roots of solder joints shall be the day away from the pin, also cannot too high welding temperature, welding time shoulds not be too long, had better use metal clips pins roots tweezers, to help the heat dissipation.
Pin bending shape of the switch should be completed before welding, welding during the pipe body and pin shall not force.