Anti-optical circuit of infrared touch screen and anti-optical method thereof

Abstract

The invention discloses an anti-optical circuit of an infrared touch screen, comprising a background light intensity acquisition unit, a background light hold circuit, a background light intensity AD conversion unit, a control singlechip, a compensation level DA conversion unit and a subtracting circuit; wherein the control singlechip is connected with and used for controlling the background light intensity acquisition unit, the background light hold circuit, the background light intensity AD conversion unit and the compensation level DA conversion unit; the input of the subtracting circuit is connected with an infrared receiving signal channel, the background light hold circuit and the compensation level DA conversion unit. The invention also provides an anti-optical method of the infrared touch screen, comprising the steps: A. acquiring background light intensity; B. transmitting effective infrared light signals; C. receiving the infrared light signals by a receiving end; D. using the received infrared light intensity to substrate the background light intensity to obtain effective intensity of the received light. The invention has the advantages that on the premise of ensuring a certain anti-optical property, the transmitting time and current of a lamp can be shortened as much as possible, a receiving circuit is simplified, the transmitting distance is prolonged, and the scanning speed is accelerated.

Description

technical field [0001] The invention relates to an anti-light circuit and an anti-light method of an infrared touch screen, especially capable of obviously improving the shortcomings of the existing infrared touch screen such as poor anti-light performance, short emission distance, and high power consumption of the whole machine. Background technique [0002] The infrared touch screen uses the dense infrared matrix in the X and Y directions to detect and locate the user's touch. The infrared touch screen installs a circuit board frame in front of the display, and the circuit board arranges infrared emitting tubes and infrared receiving tubes on the four sides of the screen, one by one corresponding to form an infrared matrix that crosses horizontally and vertically. When the user touches the screen, the finger will block the two infrared rays passing through the position, so the position of the touch point on the screen can be judged. [0003] At present, in order to weaken...

AI Technical Summary

Problems solved by technology

However, since the emission of the infrared emission tube requires a certain preheating time for the filament, otherwise the nominal luminous intensity cannot be achieved, so the existing circuit needs to occupy a long emission time or consume a large emission power, and the infrared ray The actual transmission distance is greatly shortened

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