A kind of device of hiding touch controlled key backlight that shows by infrared induction
Technical field
The utility model relates to a kind of infrared induction display device, particularly a kind of device of hiding touch controlled key backlight that shows by infrared induction.
Background technology
In video intercom and intelligent domestic system, touch controlled key is the parts that often can use, and current many touch controlled keys are all provided with background light; background light is conventionally by infrared sensing switch control, at night, when have people near time; background light can light automatically, with the keyboard that is convenient for people to use.
Human body has constant body temperature, and generally at 37 degree, so can send the infrared ray of the specific wavelength of about 10um, passive type infrared probe carries out work by surveying the infrared ray about the 10um of human-body emitting.The infrared ray of the 10um left and right of human-body emitting gathers on infrared induction source after strengthening by your optical filter of luxuriant and rich with fragrance mud.Infrared induction source adopts pyroelectricity element conventionally, and this element will lose charge balance receiving when human infrared radiation temperature changes, and outwards discharges electric charge, and subsequent conditioning circuit just can produce control signal after processing after testing.But this control mode is easily subject to various thermals source, light source, is subject to the interference of radio-frequency radiation, passive infrared penetration power is poor, the infrared radiation of human body is easily blocked, be difficult for being received by probe, and in the time that environment temperature and human body temperature approach, detection and sensitivity obviously decline, and sometimes cause malfunctioning in short-term.
Utility model content
Technical problem to be solved in the utility model is to overcome the deficiencies in the prior art, a kind of working stability, good in anti-interference performance is provided, easy to use shows by infrared induction the device of hiding touch controlled key backlight.
The technical scheme that the utility model adopts is: the utility model comprises touch controlled key and is arranged on the backlit display at described touch controlled key back, described backlit display comprises CPU, infrared transmitter, infrared remote receiver and display lamp, described infrared transmitter, described infrared remote receiver and described display lamp are all electrically connected with described CPU, it is identical with the direction of described infrared remote receiver receiving infrared-ray that described infrared transmitter is launched ultrared direction, people near time, the infrared ray of described infrared transmitter transmitting by human-body emitting to described infrared remote receiver, described infrared remote receiver sends to detection signal after described CPU again, described CPU controls described display lamp and lights.
On described touch controlled key, be provided with and described infrared transmitter and the suitable light transmission piece of described infrared remote receiver.
Described infrared transmitter comprises infrared transmitting circuit, and described infrared transmitting circuit comprises infrared-emitting diode and triode, the base stage of described triode and resistance
after series connection, be electrically connected with described CPU, the grounded emitter of described triode, described emitter and described base stage are passed through resistance
be connected, the collector of described triode is connected with the negative electricity of described infrared-emitting diode.
Described backlit display also comprises display circuit, and display lamp is light emitting diode, and described display circuit comprises resistance
, resistance
, electric capacity
and electric capacity
, described resistance
with described resistance
after in parallel, one end is connected with the negative electricity of described light emitting diode, and the other end is electrically connected with the positive pole of described infrared-emitting diode, described electric capacity
with described electric capacity
one end ground connection after in parallel, the other end is connected with the negative pole of described light emitting diode, and when use, the positive pole of described light emitting diode is connected with power supply.
Described electric capacity
with described electric capacity
for electrochemical capacitor.
Described infrared remote receiver comprises infrared receiving circuit, and described infrared receiving circuit comprises infrared receiving diode, electric capacity
, electric capacity
, electric capacity
and resistance
, described electric capacity
with described electric capacity
one end ground connection after in parallel, the pin of one end and described infrared receiving diode in addition
electrical connection; Described resistance
one termination power, the other end also with described pin
electrical connection; Described electric capacity
the pin of one end and described infrared receiving diode
electrical connection, after other end ground connection with the pin of described infrared receiving diode
electrical connection.
The beneficial effects of the utility model are: because the utility model comprises touch controlled key and is arranged on the backlit display at described touch controlled key back, described backlit display comprises CPU, infrared transmitter, infrared remote receiver and display lamp, described infrared transmitter, described infrared remote receiver and described display lamp are all electrically connected with described CPU, it is identical with the direction of described infrared remote receiver receiving infrared-ray that described infrared transmitter is launched ultrared direction, people near time, the infrared ray of described infrared transmitter transmitting by human-body emitting to described infrared remote receiver, described infrared remote receiver sends to detection signal after described CPU again, described CPU controls described display lamp and lights, so, in the time that the utility model is applied in video intercom and intelligent domestic system, because video intercom and intelligent domestic system are generally indoor use, avoid much coming from thermal source, light source and other interference source, in touch controlled key backlight, user indoor near and while touching with hand, described infrared remote receiver can receive infrared ray that human body sends and the infrared ray of described infrared transmitter transmitting simultaneously, described CPU can judge accurately, working stability, very easy to use, and described infrared transmitter can be launched the infrared ray of specific wavelength, there is good interference free performance.
Brief description of the drawings
Fig. 1 is simple structure schematic diagram of the present utility model;
Fig. 2 is the circuit diagram of described infrared receiving circuit;
Fig. 3 is the circuit diagram of described infrared transmitting circuit 41 and described display circuit 21.
Embodiment
As shown in Figure 1, in the present embodiment, the utility model comprises touch controlled key 1 and is arranged on the backlit display 2 at described touch controlled key 1 back, described backlit display 2 comprises CPU3, infrared transmitter 4, infrared remote receiver 5 and display lamp 6, described infrared transmitter 4, described infrared remote receiver 5 and described display lamp 6 are all electrically connected with described CPU3, it is identical with the direction of described infrared remote receiver 5 receiving infrared-rays that described infrared transmitter 4 is launched ultrared direction, people near time, the infrared ray that described infrared transmitter 4 is launched by human-body emitting to described infrared remote receiver 5, described infrared remote receiver 5 sends to detection signal after described CPU3 again, described CPU3 controls described display lamp 6 and lights, in the present embodiment, described touch controlled key 1 is made up of transparent material.
On described touch controlled key 1, be provided with and described infrared transmitter 4 and the suitable light transmission piece 7 of described infrared remote receiver 5.
As shown in Figure 3, described infrared transmitter 4 comprises infrared transmitting circuit 41, and described infrared transmitting circuit 41 comprises infrared-emitting diode LED1 and triode, the base stage B of described triode and resistance
after R1 series connection, be electrically connected with described CPU3, the emitter E ground connection of described triode, described emitter E and described base stage B pass through resistance
r2 is connected, and the collector C of described triode is connected with the negative electricity of described infrared-emitting diode LED1.
Described backlit display 2 also comprises display circuit 21, and display lamp 6 is LED 2, and described display circuit 21 comprises resistance
r3, resistance
r4, electric capacity
c1 and electric capacity
c2, described resistance
r3 and described resistance
after R4 parallel connection, one end is connected with the negative electricity of described LED 2, and the other end is electrically connected with the positive pole of described infrared-emitting diode LED1, described electric capacity
c1 and described electric capacity
one end ground connection after C2 parallel connection, the other end is connected with the negative pole of described LED 2, and when use, the positive pole of described LED 2 is connected with power supply.
As shown in Figure 2, described infrared remote receiver 5 comprises infrared receiving circuit, and described infrared receiving circuit comprises infrared receiving diode 51, electric capacity
c3, electric capacity
c4, electric capacity
c5 and resistance
r5, described electric capacity
c3 and described electric capacity
one end ground connection after C4 parallel connection, the in addition pin of one end and described infrared receiving diode 51
electrical connection; Described resistance
r5 mono-termination power, the other end also with described pin
electrical connection; Described electric capacity
the pin of C5 one end and described infrared receiving diode 51
electrical connection, after other end ground connection with the pin of described infrared receiving diode 51
electrical connection.
In the present embodiment, described electric capacity
c1 and described electric capacity
c2, described electric capacity
c3 is electrochemical capacitor.
In the present embodiment, under idle condition, described infrared-emitting diode LED1 always ceaselessly transmission frequency be the infrared ray of 38K HZ, when human body is near designing in sweep limit, described infrared receiving diode 51 receives that human body penetrates the infrared ray of returning outward, detection trigger signal sends to described CPU3, process and send control signal to described display circuit 21 through described CPU3 again, controlling press key lamp is the light and shade of described LED 2, working stability in whole process, very easy to use, and there is good antijamming capability.
The utility model is applied to the technical field of security protection at home.
Although embodiment of the present utility model describes with practical solution, but do not form the restriction to the utility model implication, for those skilled in the art, the amendment according to this instructions to its embodiment and with the combination of other schemes be all apparent.