Photosensitive receiver tube is one of the most common sensors. It has many varieties, such as photocell, photomultiplier tube, photoresistor, phototransistor, infrared sensor, color sensor, CCD, CMOS image sensor and so on. Next, Xiaobian introduces several commonly used photosensitive imitation sensors.
1. Infrared flame sensor:
The flame sensor can be used to detect a heat source or some other heat source with a wavelength in the range of 760 to 1100 nm, and the detection angle is 60°, and the flexibility reaches the maximum when the infrared wavelength is near 940 nm. This flame sensor plays an important role in the fire fighting robot competition or the search and rescue robot competition. It can be used as the robot's eye to find the fire source or the light source football. Separate the Arduino controller and the sensor expansion board, which can be used to manufacture the fire extinguishing robot. Soccer robots, etc. The operating temperature of the flame sensor probe is -25 ~ 85 ° C. During the operation, it must be noted that the flame sensor probe should not be too close to the flame to avoid damage.
Photosensitive receiver parameters:
1. Working voltage: +5v
2. Signal type: imitation signal
3. Working environment: -25~+85°C
4. Storage temperature: -30~+100°C
5. Acceptance wavelength: 760 ~ 1100nm
6. The following is the measured data of the flame sensor, a candle is the source of fire, and the indoor normal fluorescent lamp environment is measured:
When there is no fire source, facing the fluorescent lamp:
When there is a fire source, the sensor is spaced from it:
Since the heat and smoke of the initial fire are difficult to reach places with high space, such as theaters, warehouses, hangars, etc., smoke and temperature sensors are not suitable. Smoke and temperature sensors are also not suitable for outdoor monitoring such as oil refining workshops, forest fires, spark monitoring in pipelines for air delivery, and fire monitoring of vehicles in highway tunnels. Therefore, in order to prevent fires in special places, it is required to use a flame sensor. It is hereby stated that this flame sensor is susceptible to light and sunlight and requires special handling when it is used.
2, light sensor:
The light sensor is developed based on the principle of photoelectric effect of semiconductor. It can be used to stop the detection of ambient light intensity. Separating various single-chip controllers can complete the measurement of light, light control and photoelectric conversion. The sensor 3P is inserted. The needle interface can be separated from the sensor expansion board through the 3P sensor connection cable to create an interactive work related to light perception.
1. Power supply voltage: 3.5~5V
2. Working environment: -25~+85°C
3. Storage temperature: -30~+100°C
A photosensitive receiving tube capable of detecting light. They are small, inexpensive, low power, easy to use, and not worn. They are often presented in toys, small appliances and appliances. They are also often referred to as photoresistors (LDR).
The photocell is essentially a resistor, and the resistance of the light in the bend can change its resistance. Their cost is very low and they are easy to get in a variety of sizes and sizes. Each photosensor will be slightly different from the other sensors, even if they are the same batch. The change is also very big, often changing at around 50% or even higher! For this reason, they should not be used to try to confirm the degree of illumination or brightness to illuminate the fine light. Instead, you can only wait for a certain amount of change in the fundamental light.
From the beginning of the Nokia 7650 (with the speaker sensing in the 7650) in 2002, there is a light sensor. The benefit is that it can adjust the brightness of the screen and the keyboard light according to the light in the environment of the mobile phone.