What is a photoelectric transistor? The working principle, classification, application, and testing methods of photoelectric transistors 2

3、 Characteristics of phototransistor

1. High sensitivity: The photoelectric transistor has high sensitivity and can respond to weak light signals.

2. Fast response speed: The photoelectric transistor has a fast response speed and can respond to optical signals within microseconds.

3. Wide linear range: The photoelectric transistor has a wide linear range and can respond linearly to the intensity of different optical signals.

4. Good stability: Phototransistors have good stability and can maintain good performance under different environmental conditions.

5. Easy to integrate: Phototransistors come in various packaging forms and are easy to integrate into other circuits.

4、 The Application of Phototransistors

1. Optoelectronic control: Phototransistors can convert optical signals into electrical signals, which can be used for the photoelectric control function of circuits.transistor

2. Optoelectronic measurement: Phototransistors can efficiently convert optical signals and can be applied in the field of optoelectronic measurement.

3. Optoelectronic detection: Phototransistors can linearly respond to the intensity of different optical signals and can be applied in the field of optoelectronic detection.transistor

4. Optoelectronic amplification: Phototransistors can amplify weak optical signals and can be applied in the field of optoelectronic amplification.

5. Optoelectronic isolation: Phototransistors can achieve the photoelectric isolation function of circuits and can be applied in some special circuit designs.transistor

5、 Testing methods for phototransistors

1. Photocurrent testing

The photocurrent test is the most basic testing method for phototransistors, which can be used to detect the sensitivity and response speed of the device. During testing, shine the light source on the photosensitive area of the phototransistor and measure the output photocurrent. The magnitude of photocurrent is directly proportional to the intensity of the light source, and the sensitivity of the phototransistor can be tested by changing the intensity of the light source. The response speed can be evaluated by measuring the rise time and fall time of the photocurrent.

2. Photovoltaic voltage test

Photovoltage testing is a method of measuring the output voltage of a phototransistor, which can be used to detect the linearity and voltage gain of the device. During testing, shine the light source on the photosensitive area of the phototransistor and measure the output photovoltaic voltage. The magnitude of the photovoltaic voltage is directly proportional to the intensity of the light source, and the linearity and voltage gain of the phototransistor can be tested by changing the intensity of the light source.

3. Noise testing

Noise testing is a method of testing the noise index of phototransistors, which can be used to evaluate the signal-to-noise ratio and noise level of the device. During testing, shine the light source on the photosensitive area of the phototransistor and measure the output noise voltage or noise current. The magnitude of noise voltage or noise current is independent of the intensity of the light source, and the noise performance of the device can be evaluated by testing the noise level of the phototransistor