Visible light sensor

Abstract

The invention discloses a visible light sensor which mainly solves the problem of low precision because of the influence of dark current and noise because infrared light can not be effectively inhibited in the prior art. The visible light sensor comprises an ambient light detection circuit (1), an infrared light detection circuit (2), a current control circuit (3), an analog digital conversion circuit (4), a time sequence control circuit (5), a reference voltage generation circuit (6), a reference current generation circuit (7) and a data storage circuit (8), wherein an optical signal detected by the ambient light detection circuit is converted into a current signal; the current signal and a current signal converted from an infrared light detection signal are operated by the current control circuit; an operation result is output to the analog digital conversion circuit; the analog digital conversion circuit sends a conversion result to an external microprocessor by the data storage circuit; and the time sequence control circuit provides a time sequence control signal for all circuits. The visible light sensor owns two measuring ranges, infrared light can be effectively inhibited, the dark current is eliminated, flicker noise in a manual light source is filtered, and the visible light sensor mainly responds to visual light and can be applied to intelligent control of electronic products.

Description

technical field [0001] The invention belongs to the technical field of electronic devices and relates to a light sensor, which can be used in the intelligent control of portable devices such as computers, mobile phones, tablet computers and PDAs, and televisions. Background technique [0002] In recent years, the development of liquid crystal display (LCD) has advanced by leaps and bounds, and it plays a decisive role in the field of flat panel display. Televisions, computers, mobile phones, and tablet computers using liquid crystal display devices as display screens are widely used. LCD is a light valve display that modulates lamp or ambient light. It does not emit light itself, but only reflects or transmits external light. Reflective LCD has low brightness and poor color gamut, and is used in low-power applications, such as watches, etc. It is not suitable for the display of TVs, computers, mobile phones and tablet computers, and transmissive LCDs are generally used. Wh...

AI Technical Summary

Problems solved by technology

However, the existing ambient light sensor does not suppress the infrared light in the ambient light to a high degree; the photodiode PD contained in the ambient light sensor has the problem of generating dark current itself, and the dark current is greatly affected by the voltage. Indistinguishable from photocurrent, which will lead to inaccurate results; in artificial light sources, the ambient light sensor is also affected by 50Hz / 60Hz flicker noise, the above factors affect the response accuracy of the ambient light sensor to visible light, thus affecting the ambient light sensor in The effect of adjusting the brightness of the backlight in the LCD backlight system reduces the effect of people watching the LCD in different ambient light

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