CN213880342U

CN213880342U - Intelligent eyesight protector based on PWM dimming

Info

Publication number: CN213880342U
Application number: CN202022758448.3U
Authority: CN
Inventors: 陈冬英
Original assignee: Fujian Jiangxia University
Current assignee: Fujian Jiangxia University
Priority date: 2020-11-25
Filing date: 2020-11-25
Publication date: 2021-08-03
Anticipated expiration: 2030-11-25

Abstract

The utility model provides an intelligence eyesight protector based on PWM adjusts luminance, include: microcontroller and with microcontroller is connected: ultrasonic ranging device, light detection dimmer circuit and infrared human detection device. The myopia-preventing and eyesight-protecting lamp is simple in structure, rich in functions and strong in practicability, and can provide an intelligent lighting environment for myopia prevention and eyesight protection.

Description

Intelligent eyesight protector based on PWM dimming

Technical Field

The utility model belongs to the technical field of the eyesight protector, especially, relate to an intelligence eyesight protector based on PWM adjusts luminance.

Background

Juvenile myopia is one of the focus of social attention. In addition, the requirements of various occupations of the current society on vision are only increased, but many people say that the medical technology is more and more developed now, and the vision can be recovered through operations such as laser, but the method for recovering the vision has hidden troubles, symptoms do not appear at the moment after the operation, the vision is not always safe, and the technology is not available at present, and the original vision can be completely recovered. In the middle and primary schools of children, the primary school is a key period for protecting and correcting vision, and the primary school cannot be recovered once the primary school is missed. This period may be purely physical to protect or correct vision.

It is considered that many children are mainly short-sighted because they are too close to the desktop when writing or reading a book, or they are reading or writing under the environment of too dark or too strong light, which causes eyestrain. The reason of myopia is that parents do not pay attention to the eyesight protection of children from childhood and lack of related knowledge. The situation that 41.6% of students with mild myopia are not corrected in time becomes irretrievable is caused.

SUMMERY OF THE UTILITY MODEL

Not enough and blank to prior art exists, the utility model provides an intelligence eyesight protector based on PWM adjusts luminance, through the efficiency of giving the regulation of light intensity to alleviate user of service's burden with the eye, in order to play the efficiency of protection eyesight.

The utility model discloses specifically adopt following technical scheme:

the utility model provides an intelligence eyesight protector based on PWM adjusts luminance which characterized in that includes: microcontroller and with microcontroller is connected: ultrasonic ranging device, light detection dimmer circuit and infrared human detection device.

Preferably, the system further comprises, connected to the microcontroller: the device comprises a display module, a voice prompt module and an acousto-optic alarm module.

Preferably, the ultrasonic ranging apparatus includes: an HC-SR04 module and a temperature compensation circuit; the light detection dimming circuit comprises: the LED drive circuit comprises a photosensitive resistor, an AD conversion circuit, a PWM dimming circuit and an LED; the infrared human body detection device adopts an HC-S501 module.

Preferably, the light detection dimming circuit further comprises a manual dimming module.

Preferably, the microcontroller employs an STC89C52 chip.

The utility model discloses and preferred scheme structure retrencies, the function is abundant, and the practicality is strong, can provide intelligent daylighting environment for preventing and treating myopia and protection eyesight.

Utilize ultrasonic ranging, adopt light detection circuit to realize PWM and adjust luminance to provide voice prompt and audible-visual alarm circuit, gather external signal through infrared human detection device and AD converting circuit, and reach this signal and carry out the operation processing to the singlechip, and control each module and adjust.

Whether a person exists in the sensing area is detected by adopting the HC-SR501 human body sensing module so as to realize and start functions of learning countdown and the like. Meanwhile, the light detection and adjustment function adopts a PWM dimming technology, can automatically adjust the light of the LED lamp according to the ambient light condition, and has a manual control alternative function.

Drawings

The invention will be described in further detail with reference to the following drawings and detailed description:

fig. 1 is a schematic view of the overall structure of an embodiment of the present invention;

fig. 2 is a schematic view of the working flow of the embodiment of the present invention;

fig. 3 is a schematic diagram of the internal structure of STC89C52 according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of an ultrasonic ranging pulse according to an embodiment of the present invention;

fig. 5 is a functional schematic diagram of a temperature compensation circuit according to an embodiment of the present invention;

fig. 6 is a schematic structural diagram of a light detection dimming circuit according to an embodiment of the present invention;

fig. 7 is a schematic diagram of a principle of an LED driving circuit according to an embodiment of the present invention;

fig. 8 is a schematic diagram of a light detection circuit according to an embodiment of the present invention;

FIG. 9 is a schematic diagram of the infrared human body detection circuit according to the embodiment of the present invention;

fig. 10 is a schematic diagram of a circuit buzzer according to an embodiment of the present invention.

Detailed Description

In order to make the features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail as follows:

the intelligent vision protector device based on PWM adjusts luminance that this embodiment provided, the structure of its design mainly includes ultrasonic ranging circuit, light detection PWM regulating circuit, voice prompt correction circuit, hand automatic switch button and audible-visual alarm circuit isotructure.

The functions required to be realized can comprise: when the infrared human body detection device detects a human body, the infrared human body detection device is automatically started, a learning countdown mode is automatically carried out, and when the time is over, the voice system is started. When in the learning mode, the light intensity is collected through the AD collection device, if the light exceeds the limited upper and lower values, the PWM circuit is started to automatically adjust the light, manual/automatic switching can also be carried out, and the addition and subtraction keys are used for manually adjusting the light. The ultrasonic distance measuring module is used for detecting the measured distance, the distance is smaller than a set range, the acousto-optic alarm is started, and a temperature compensation circuit is added to enable the measured value to be more accurate. And the obtained result is transmitted to the LCD through the singlechip to display the change condition of the light and the distance value in real time.

The key technology is as follows:

(1) and setting the light intensity, and performing PWM automatic dimming according to ambient light.

(2) And (4) ultrasonic distance detection, which is smaller than a limited set distance, and automatic voice prompt.

(3) The infrared human body detection can detect whether a person exists or not, and the learning countdown device is automatically started.

(4) The LCD displays the distance and light intensity in real time.

(5) The manual dimming can be carried out according to the ambient light condition.

The embodiment details the design scheme of the specific hardware structure for implementing the above functions:

the general hardware block diagram of this embodiment is shown in fig. 1, and the general hardware block diagram is divided into seven major modules, including LCD display module, core control module, light detection dimming system, ultrasonic ranging system, voice prompt system, infrared human body detection module, acousto-optic alarm system. The work flow is shown in fig. 2.

In order to achieve the above task, the present embodiment adopts the following hardware technical solutions:

1. designing a main control module: the most important of this embodiment is the core control module, and the main chip to be used in this embodiment is STC89C 52. STC89C52 has the advantages of flexibility and multiple effects, and is a COMS 8-bit microcontroller with 8-bit CPU and Flash programmable in the system. This performance feature will greatly reduce the power consumed by the whole circuit and provide an efficient operation processing speed. The Flash memory which can be repeatedly erased and written 1000 times is the advantage. More importantly, the device can be used for realizing complex and changeable control by programming, is convenient to operate and strong in practicability, and can easily complete functions of light intensity detection, ultrasonic distance detection and the like in the design. The internal structure of STC89C52 is shown in fig. 3.

2. Ultrasonic detection design: the ultrasonic detection circuit of the embodiment mainly comprises an HC-SR04 module and a temperature compensation circuit.

(1) Ultrasonic ranging circuit: the interface sends > =10us pulse trigger signal to the trigger pin, 8 periodic level of 40kHz, will send out from the module inside, detect whether there is echo simultaneously, once receive echo signal, then output the echo signal, the distance measured is directly proportional with echo signal's pulse width, through calculating from launching to the time interval of receiving the signal like this, thereby calculate the distance. The ultrasonic ranging pulse diagram is shown in fig. 4.

(2) The temperature compensation circuit: since the low temperature coefficient oscillation frequency has less influence with temperature, a signal for generating a fixed pulse is stored in the counter 1. The high temperature oscillation signal has a large influence with the temperature, the generated signal is stored in the counter 2, and the counter 1 and the temperature register preset a base value at the temperature of-55 ℃. The pulse signal generated by the low temperature frequency in the counter 1 is counted down, when the value in the counter 1 becomes 0, the value of the temperature register is increased by 1, and the preset value is reloaded back to the counter 1. And a new round of subtraction counting is restarted until the value of the counter 2 becomes 0, the temperature register stops accumulating, and the measured temperature is the value in the temperature register. The temperature compensation function diagram is shown in fig. 5.

3. The light detection dimming circuit is designed as follows: in this embodiment, an AD conversion and PWM dimming circuit is used to detect the intensity of detected light and adjust the light of the LED lamp with respect to the detected light. The light detection dimming function diagram is shown in fig. 6.

(1) LED drive

The LED adjusts the brightness of the USB lamp through the control of current. From I_L=t_onI/T can know that the control of the current magnitude and the duty ratio T are realized_onThe key point is that J6 is a USB lamp, the triode Q3 provides conduction current for the USB lamp, PWM is output by the LED network label end, and the LED network label end normally works at low level. The LED driving diagram is shown in fig. 7.

(2) Manual mode

In the embodiment, the brightness of the LED lamp is adjusted in a grading manner by arranging the key switch, and a manual or automatic mode is adjusted by one mode change-over switch.

(3) Automatic mode

Adopting photoresistor feedback: the intensity of ambient light is judged by adopting a photosensitive resistor with photoelectric effect and through the change of the resistance value. The single chip microcomputer controller receives the feedback result and transmits the feedback result to the interior to start the next processing. The photoresistor can be widely applied to the aspects of light measurement, conversion, control and the like. The system collects the change condition of ambient light by continuously collecting the voltage to ground. Chip ADC0832 is mainly used. Setting the reference voltage of the ADC0832 to be 5V, connecting a clock signal with a corresponding port of the single chip microcomputer through CLK, and interrupting output by using a timer of the single chip microcomputer. The voltage collected by the photoresistor is input from CW0 port, ADC0832 converts the analog signal into digital quantity, and outputs it from D0-1 port to be transmitted to single-chip microcomputer for precision processing. The light detection circuit diagram is shown in fig. 8.

4. Infrared human body induction design: the present embodiment employs the HC-S501 module. J5 is infrared human body induction module interface among this circuit, and when sensing someone, then 2 nd pin output high level, under the current limiting effect of R14, triode Q2 is switched on, and the projecting pole is in the low level state, and the collecting electrode ground connection of Q2 this moment, then pilot lamp D5 is lighted. Whether someone is present is known by observing whether the indicator light is illuminated. Wherein, R13 is a pull-up resistor, when the target is not in the sensing range, the triode is not conducted, and the emitter is changed from low level to high level under the action of the pull-up resistor. The infrared human body detection circuit diagram is shown in fig. 9.

5. Designing an audible and visual alarm circuit: in this embodiment, a 9013 NPN transistor is used, so that the operation of the buzzer and the indicator light can be controlled by the input high and low levels, and when the input voltage is high level, the transistor is turned on, and the buzzer and the indicator light are grounded. Otherwise, when the input voltage is low level, the triode is cut off, and the buzzer and the LED do not work. As shown in fig. 10, where R8 is a pull-up resistor, the operation of the buzzer is not affected only by increasing the current. And R9 and R10 play the role of current limiting and are used for protecting the indicator light and the triode.

The present invention is not limited to the above-mentioned preferred embodiments, and other various forms of intelligent vision protectors based on PWM dimming can be obtained by anyone who can benefit from the teaching of the present invention.

Claims

1. The utility model provides an intelligence eyesight protector based on PWM adjusts luminance which characterized in that includes: microcontroller and with microcontroller is connected: the device comprises an ultrasonic ranging device, a light detection dimming circuit and an infrared human body detection device;

the ultrasonic ranging apparatus includes: an HC-SR04 module and a temperature compensation circuit; the light detection dimming circuit comprises: the LED drive circuit comprises a photosensitive resistor, an AD conversion circuit, a PWM dimming circuit and an LED; the infrared human body detection device adopts an HC-S501 module.

2. The intelligent vision protector based on PWM dimming according to claim 1, wherein: further comprising connected to the microcontroller: the device comprises a display module, a voice prompt module and an acousto-optic alarm module.

3. The intelligent vision protector based on PWM dimming according to claim 1, wherein: the light detection dimming circuit further comprises a manual dimming module.

4. The intelligent vision protector based on PWM dimming according to claim 1, wherein: the microcontroller employs an STC89C52 chip.