The measurement starts with the continuous emission of an infrared signal from an infrared emitting diode to the target object. The emitted infrared rays are reflected by the object and the reflection is detected by a special photocell sensitive to infrared rays. The photocell (located next to the IR transmitter), the reflection point and the infrared transmitter are arranged in a triangle with each other. Depending on the measuring device, the determination of the distance can be divided into two different evaluation methods, based on triangulation or time.

Variant one is based on the triangulation principle. The light returning from the reflection point is focused by a lens located in front of the photocell. The result is a focused infrared beam, whose point of impact on the photodiode gives information about the angle of incidence, based on which the infrared rangefinder calculates the distance to the object. In this case, the infrared evaluation depends on the intensity of the incident light. This type of infrared distance measurement is used, for example, for national mapping.

In variant 2, the transit time from the emission of the infrared signal to the detection of the reflection is determined. The distance between the two points can be determined by the known distance between the sensor and the receiver and by the speed of the IR rays stored in the device in combination with the determined time. This technology can be applied from hunting to vehicle parking assistance.

Requirements for infrared optics

The daily applications of infrared optics place increasing demands on their performance and durability. Consistently good imaging performance and a compact and robust design enable them to be optimally used in various fields, such as the automotive industry. Thanks to AceFire's efficient and durable infrared optics, they can be easily adapted to your individual needs and can withstand mechanical and thermal influences.