DOME stands for Digital Optical Measurement and Evaluation
The principle:
Short (also time discontinuous) pulses of light are transmitted via an LED which then strike a photodiode whenever they are reflected by an object such as a hand, etc. Depending upon the movement of the detected object or hand, the resulting signal exhibits a specific, ascertainable characteristic.
In order to evaluate this reflected useful signal, it is necessary to exclude factors of influence that interfere with the photodiode. Interfering influences can result from surrounding light, extraneous light, surface changes, dust or moisture or from mechanical changes of the operating surface. Any disturbances affecting the photodiode are eliminated using a closed loop control, designed with analog technology.
The software then compares the useful signal with a stored profile. The profile contains the definition that specifies what the sensor is supposed to achieve as a part of a product (see also “Areas of application”).
The sensor is constructed discretely using conventional components so that availability of the necessary components is guaranteed. If the sensor technology is an integral part of the product, then a separate IC is not even necessary. RAM/ROM requirements are minimal.
The basic logic function of DOME requires an LED in the optical frontend and a photodiode. If the sensor technology requirements go beyond a single “control point”, a more complex application will be required and more than one LED must be used. However, from a physical standpoint, no more than one receiver is necessary. The construction of the complete sensor electronics increases less than proportionally since the actual DOME electronics (hardware and software) require only minimal adaptation beyond the optical frontend.
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