Photo-electric signal receiving circuit used for an infrared touch screen
A technology of infrared touch screen and receiving circuit, which is applied in electrical digital data processing, input/output process of data processing, instruments, etc., can solve the problems of difficult design, difficult to meet signal amplification, difficult amplifier design, etc., and achieve the effect of simplifying design
Inactive Publication Date: 2012-01-11
BEIJING UNITOP NEW TECH CO LTD
View PDF6 Cites 0 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
This makes amplifier design difficult
Especially at present, the amplifiers of infrared touch screens are powered by a single power supply, which makes it more difficult to design.
At the same time, when the performance of the photoelectric receiving tube changes with time, temperature and other conditions, the original amplifier design is more difficult to meet the needs of signal amplification.
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0023] image 3 A schematic diagram of the most basic circuit principle of the present invention is given. As shown in the figure, on the connection channel between the DC blocking coupling capacitor Cin of the photoelectric signal amplification channel and the input terminal of the photoelectric signal amplifier Ap, a grounding switch SW is set; the output terminal of the amplifier and the grounding switch The control ends are all connected with the I / O interface of the microcontroller system that controls the work of the touch screen. JL1 and JL2 in the figure are still cross-connection coupling elements.
[0024] Since the infrared emitting and receiving circuits of infrared touch screens are generally in a matrix structure, the commonly used basic circuit structures are based on the technical solutions disclosed in US patents No. 3,764,813, 3,775,560 and 3,860,754 and Chinese patent application No. 00121462. It is also often divided into several groups, that is, one row ...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
Login to View More Abstract
The invention relates to a photo-electric signal receiving circuit used for an infrared touch screen, comprising an infrared receiving pipe, a detecting resistor, a blocking condenser and an earthing switch, wherein the detecting resistor is connected in series with the infrared receiving pipe; the blocking condenser is respectively connected with the input ends of the detecting resistor and an infrared photo-electric signal amplifier by coupling elements; the earthing switch is connected between a connecting passage of the blocking coupling condenser and the infrared signal amplifier and thecommon end of input signals; and the control end is coupled and connected with an I / O port of a microcontroller controlling the whole infrared touch screen to work. The invention returns uncertained DC potentials of the input end of the amplifier to zero by the earthing switch before starting to detect the infrared signals, solves the problem that the amplifier in the prior photo-electric signal receiving circuit needs to be provided with a DC operating point in advance, greatly simplifies amplifier design and can ensure the adaptability and operating stability of an amplifying circuit when the performance of the receiving pipe is changed.
Description
technical field [0001] The invention relates to a photoelectric signal receiving and processing circuit for an infrared touch screen, which belongs to the field of photoelectric technology, in particular to the field of photoelectric signal processing technology used in an infrared touch screen. Background technique [0002] Existing photoelectric signal receiving and processing circuits for infrared touch screens have various structures, such as using an expensive instrumentation amplifier to directly sample and hold the amplification structure; wait. There are other circuits too, too many to list. figure 1 The principle of a relatively commonly used circuit is given. An infrared signal receiving circuit composed of multiple identical channels, such as 8 channels, selects which channel is connected to the input terminal of the main amplifier Ap at a certain moment by switching the switch TS. Taking the first path as an example, the photoelectric signal generates a voltage...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & Authority Patents(China)
IPC IPC(8): G06F3/042
Inventor 刘建军刘新斌叶新林
Owner BEIJING UNITOP NEW TECH CO LTD