Double-optical-filter switching circuit, double-optical-filter switcher and camera

Abstract

The utility model relates to the technical field of video monitoring, in particular to a double-optical-filter switching circuit, a double-optical-filter switcher and a camera, the double-optical-filter switching circuit comprises a signal control unit and a half-bridge circuit, the output end of the signal control unit is connected with the input end of the half-bridge circuit, and the output end of the signal control unit is connected with the input end of the half-bridge circuit. The output end of the half-bridge circuit is connected with the driving end of the double-optical-filter switcher, and the half-bridge circuit controls the double-optical-filter switcher to switch work based on the control signal output by the signal control unit. Therefore, according to the invention, the half-bridge circuit controls the switching work of the double-optical-filter switcher based on the control signal output by the signal control unit, so that the problem that the double-optical-filter switcher cannot be switched due to voltage drop is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of video monitoring, in particular to a double-filter switching circuit, a double-filter switcher and a camera. Background Art

[0002] With the continuous advancement and development of technology, competition in various electronic products is becoming increasingly fierce, especially in the security video surveillance industry. Manufacturers are increasingly stringent in their product cost requirements. Dual filter switchers are an essential component of security video surveillance cameras.

[0003] Currently, dual-filter switches on the market are typically powered by a 12V adapter. However, these 12V adapters vary in technology and quality, and are prone to voltage drops, making them insufficient to power the dual-filter switch. This results in infrared and other stray light entering the CCD or CMOS during the day, interfering with color reproduction and causing a reddish image cast. At night, low-light performance deteriorates. Therefore, addressing the issue of dual-filter switches being unable to switch due to voltage drops has become a pressing issue. Utility Model Content

[0004] Based on this, it is necessary to provide a dual filter switching circuit, a dual filter switcher and a camera to address the above technical problems, so as to solve the problem that the dual filter switcher cannot switch due to voltage drop.

[0005] In order to solve the above technical problems, the first aspect of the present invention provides a dual-filter switching circuit, characterized in that the dual-filter switching circuit includes a signal control unit and a half-bridge circuit;

[0006] The output end of the signal control unit is connected to the input end of the half-bridge circuit, and the output end of the half-bridge circuit is connected to the driving end of the dual-filter switch;

[0007] The half-bridge circuit controls the switching operation of the dual-filter switch based on the control signal output by the signal control unit.

[0008] Optionally, the half-bridge circuit includes a driving power supply, a first switching element and a second switching element, the first end of the first switching element is used to connect to the negative end of the driving power supply, the second end of the first switching element is connected to the first end of the second switching element, the second end of the second switching element is used to connect to the positive end of the driving power supply, the control ends of the first switching element and the second switching element are respectively connected to the output end of the signal control unit, and the second end of the first switching element and the first end of the second switching element are both connected to the driving end of the dual filter switch.

[0009] Optionally, the driving power supply is 5V / 4.2V.

[0010] Optionally, both the first switching element and the second switching element are MOS transistors.

[0011] Optionally, the control signal includes a high control signal and / or a low control signal.

[0012] The second aspect of the present invention provides a dual-filter switch, which includes a first filter, a second filter, a switching mechanism and a dual-filter switching circuit as described in any one of the first aspects above, and the switching mechanism is respectively connected to the first filter, the second filter and the half-bridge circuit in the dual-filter switching circuit.

[0013] The third aspect of the present invention provides a camera, which includes a main control chip and a lens module. The lens module includes an optical lens, an image sensor and the dual filter switch described in the second aspect. The dual filter switch is arranged between the optical lens and the image sensor, and the dual filter switch and the image sensor are both connected to the main control chip.

[0014] In summary, the present invention provides a dual-filter switching circuit, a dual-filter switch, and a camera. The dual-filter switching circuit includes a signal control unit and a half-bridge circuit. The output of the signal control unit is connected to the input of the half-bridge circuit, and the output of the half-bridge circuit is connected to the drive end of the dual-filter switch. The half-bridge circuit controls the switching operation of the dual-filter switch based on a control signal output by the signal control unit. As can be seen, the present invention uses a half-bridge circuit to control the switching operation of the dual-filter switch based on a control signal output by the signal control unit. This simple control method solves the problem of the dual-filter switch being unable to switch due to a voltage drop. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0016] Figure 1 This is a structural diagram of a dual filter switching circuit provided by an embodiment of the present utility model;

[0017] Figure 2 This is a structural diagram of a camera provided by one embodiment of the present utility model. DETAILED DESCRIPTION

[0018] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0019] In the description of the present invention, it should be understood that descriptions involving orientation, such as up, down, left, right, front, back, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0020] In the description of this utility model, if there is a description of first and second, it is only for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0021] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0022] In order to illustrate the technical solution of the present invention, specific embodiments are provided below for description.

[0023] The utility model provides a dual filter switching circuit, such as Figure 1 As shown, the dual-filter switching circuit includes a signal control unit and a half-bridge circuit. The output end of the signal control unit is connected to the input end of the half-bridge circuit, and the output end of the half-bridge circuit is connected to the driving end of the dual-filter switch. The half-bridge circuit controls the switching operation of the dual-filter switch based on the control signal output by the signal control unit. It can be seen that when the input end of the half-bridge circuit receives the control signal, the switch state in the half-bridge circuit is adjusted by the control signal, and the output signal is transmitted to the driving end of the dual-filter switch, thereby realizing the switching operation of the dual-filter switch.

[0024] Specifically, the switching operation of the dual filter switch IR-CUT includes two switches: forward opening and reverse opening. During operation, when it is daytime or when the light is strong, the output of the control signal output circuit is low, and the filter switching drive circuit controls the dual filter switch IR-CUT to open in the forward direction, that is, the infrared filter in the dual filter switch IR-CUT is turned on and the CCD or CMOS restores the true color; when it is night or when the light is weak, the output of the control signal output circuit is high, and the filter switching drive circuit controls the dual filter switch IR-CUT to open in the reverse direction, that is, the infrared filter in the dual filter switch IR-CUT is turned off and the full-spectrum filter starts to work, so that the CCD or CMOS can fully utilize all the light, thereby greatly improving the low-light performance. The present application controls the level states of the two input terminals of the half-bridge circuit respectively through two control lines to realize the forward and reverse switching of the output current, so as to accurately and quickly enable the dual filter switch to realize the switching operation.

[0025] In one embodiment, the half-bridge circuit includes a driving power supply, a first switching element and a second switching element, the first end of the first switching element is used to connect to the negative end of the driving power supply, the second end of the first switching element is connected to the first end of the second switching element, the second end of the second switching element is used to connect to the positive end of the driving power supply, the control ends of the first switching element and the second switching element are respectively connected to the output end of the signal control unit, and the second end of the first switching element and the first end of the second switching element are both connected to the driving end of the dual filter switch.

[0026] Specifically, the half-bridge circuit includes a driving power supply, a first switching element, and a second switching element. The first end of the first switching element is connected to the negative end of the driving power supply, the second end of the first switching element is connected to the first end of the second switching element, and the second end of the second switching element is connected to the positive end of the driving power supply. The control ends of the first and second switching elements are respectively connected to the output end of a signal control unit, and the second end of the first switching element and the first end of the second switching element are respectively connected to the driving end of a dual-filter switch. By controlling the second switching element to conduct and the first switching element to cut off, the dual-filter switch IR-CUT switching action is achieved, and the output current can be controlled to flow in the forward direction, that is, from right to left through the motor. By controlling the first switching element to conduct and the second switching element to cut off (at this time, the current is in a static state), the output current can be controlled to flow in the reverse direction, that is, from left to right through the motor. It can be seen that the half-bridge circuit controls the switching states of two switching elements through at least two control lines to achieve switching of the current direction. When the input end of the half-bridge circuit receives a control signal, the control signal is used to adjust the switching states of the first switching element and the second switching element respectively to adjust the current direction of the output current corresponding to the half-bridge circuit, that is, to determine whether the current direction is forward or reverse. The forward direction is when the output current flows from the second switching circuit to the drive circuit, and the reverse direction is when the output current flows from the drive circuit to the first switching circuit, thereby realizing the switching operation of the dual filter switch.

[0027] In one embodiment, the driving power supply is 5V / 4.2V.

[0028] Specifically, the driving power supply is 5V / 4.2V. When using the Darlington circuit, the existing 12V high voltage power supply in the circuit design is required, but the driving voltage of the dual filter switch IR-CUT is 3.5-6V, so it is necessary to configure a voltage divider resistor. However, the adapters on the market are uneven, and the voltage drop range cannot be determined. If the voltage divider resistor is designed according to 12V, it will not be suitable for the dropped voltage, and the hidden danger is relatively large. This application uses 5V / 4.2V voltage, the internal voltage is stable, and the output does not require a voltage divider resistor to match the dual filter switch IR-CUT driving capability, which can effectively avoid the input power supply voltage drop.

[0029] In one embodiment, both the first switch element and the second switch element are MOS transistors.

[0030] Specifically, the first switching element and the second switching element are both MOS transistors. MOS transistors have low on-resistance and switching time, which enables the switching circuit to perform energy conversion with high efficiency and reduce energy waste. During the switching process, the MOS transistor can achieve low power consumption, thereby helping to reduce the energy consumption of the entire circuit system. The present application can integrate two MOS transistors into a half-bridge circuit. The gate voltages of the two MOS transistors are controlled separately by the control signals output by the signal control unit, which can conveniently control the on and off states of the MOS transistors, thereby achieving precise switching control. Furthermore, the voltage drop of the MOS transistor of the present application is smaller than that of a triode, which can avoid the situation where the input power supply voltage drops.

[0031] In one embodiment, the control signal includes a high control signal and / or a low control signal.

[0032] Specifically, the control signal includes a high control signal and / or a low control signal. Since the control ends of the first switching element and the second switching element are respectively connected to the output end of the signal control unit, the gate voltages of the two MOS tubes are respectively controlled by the control signals output by the signal control unit. When the control signal A is a high-level signal and the control signal B is a low-level signal, the second MOS tube M2 will be turned on and the first MOS tube M1 will be turned off, and the 5V / 4.2V power supply will output driving power to the output signal to realize the dual-filter switch IR-CUT switching action; and when the control signal A is a low-level signal and the control signal B is a high-level signal, the first MOS tube M1 will be turned on and the second MOS tube M2 will be turned off, and it is static at this time.

[0033] The dual-filter switching circuit of the present invention uses a half-bridge circuit based on the control signal output by the signal control unit to adjust the corresponding switching states of the first switching element and the second switching element using two control lines, so that the 5V / 4.2V power supply will output driving power to the output signal, thereby controlling the dual-filter switch to achieve switching. Its control method is simple, thereby solving the problem of the dual-filter switch being unable to switch due to voltage drop.

[0034] An embodiment of the present utility model also provides a dual-filter switch, which includes a first filter, a second filter, a switching mechanism and a dual-filter switching drive circuit as described in any of the above items, and the switching mechanism is respectively connected to the first filter, the second filter and the half-bridge circuit in the dual-filter switching drive circuit.

[0035] Specifically, for a camera with an infrared night vision function, the first filter and the second filter can both be infrared cutoff filters or full high-transmittance filters, and the first filter and the second filter are different. Taking the case where the first filter is an infrared cutoff filter and the second filter is a full high-transmittance filter as an example, when there is sufficient light during the day, the switching states of the first switch element and the second switch element in the half-bridge circuit can be controlled by controlling the level state of the control signal, that is, the second switch element is turned on and the first switch element is turned off.

[0036] The switching mechanism determines that the first filter is in the tooling state, filters out infrared light, and restores the true picture color on the image sensor; when there is insufficient light at night, the switching state of the first switching element and the second switching element in the half-bridge circuit can be controlled by controlling the level state of the control signal, that is, the second switching element is cut off and the first switching element is turned on. The switching mechanism switches the second filter to the tooling state and removes the first filter. The fully highly transparent second filter starts to work. The fully highly transparent second filter allows all light to pass through, so that the image sensor can obtain more ambient light to improve the contrast and clarity of the black and white image on the image sensor, thereby improving the image display effect.

[0037] It should be noted that the switching mechanism can be an electromagnetic, motor or other power source, which is mainly controlled by two wires to control the forward and reverse rotation of the motor to meet the needs of switching the filter. This application does not impose any restrictions on this.

[0038] The dual-filter switch provided by the present invention connects the second end of the first switching element and the first end of the second switching element in the half-bridge circuit to the driving end of the dual-filter switch, and the control ends of the first switching element and the second switching element are respectively connected to the output end of the signal control unit. Two control lines are used to adjust the corresponding switching states of the first switching element and the second switching element so that the 5V / 4.2V power supply will output driving power to the output signal, thereby controlling the dual-filter switch to achieve switching operation. The control method is simple, thereby solving the problem of the dual-filter switch being unable to switch due to voltage drop.

[0039] The embodiment of the utility model further provides a camera, Figure 2 This is a schematic diagram of the connection of the camera provided by the utility model. Figure 2 As shown, the camera 20 includes: a main control chip 21 and a lens module 22, the lens module includes an optical lens, an image sensor and a dual filter switch of any of the above items, the dual filter switch is arranged between the optical lens and the image sensor, and the dual filter switch and the image sensor are both connected to the main control chip.

[0040] It should be noted that the main control chip can be an ISP (Image Signal Processing) chip or a SoC (System on Chip) chip, and this application does not impose any limitation on this.

[0041] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A dual filter switching circuit, characterized in that: The dual filter switching circuit includes a signal control unit and a half-bridge circuit; The output end of the signal control unit is connected to the input end of the half-bridge circuit, and the output end of the half-bridge circuit is connected to the driving end of the dual-filter switch; The half-bridge circuit controls the switching operation of the dual-filter switch based on the control signal output by the signal control unit.

2. The dual filter switching circuit according to claim 1, wherein: The half-bridge circuit includes a driving power supply, a first switching element and a second switching element, the first end of the first switching element is used to connect to the negative end of the driving power supply, the second end of the first switching element is connected to the first end of the second switching element, the second end of the second switching element is used to connect to the positive end of the driving power supply, the control ends of the first switching element and the second switching element are respectively connected to the output end of the signal control unit, and the second end of the first switching element and the first end of the second switching element are both connected to the driving end of the dual filter switch.

3. The dual filter switching circuit according to claim 2, wherein: The driving power supply is 5V / 4.2V.

4. The dual filter switching circuit according to claim 2, wherein: The first switching element and the second switching element are both MOS transistors.

5. The dual filter switching circuit according to claim 1, wherein: The control signal includes a high control signal and / or a low control signal.

6. A dual filter switch, characterized in that: The dual-filter switch includes a first filter, a second filter, a switching mechanism and the dual-filter switching circuit according to any one of claims 1 to 5, and the switching mechanism connects the first filter, the second filter and the half-bridge circuit in the dual-filter switching circuit respectively.

7. A camera, characterized in that: The camera includes a main control chip and a lens module, the lens module includes an optical lens, an image sensor and the dual filter switch according to claim 6, the dual filter switch is arranged between the optical lens and the image sensor, and the dual filter switch and the image sensor are both connected to the main control chip.

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