An adaptive detection circuit for triggering signal of fill light

Abstract

The embodiment of the present invention discloses an adaptive detection circuit for a fill light trigger signal. The adaptive detection circuit for the fill light trigger signal comprises: a signal isolation circuit for isolating an input external signal; a logic control circuit, the logic control circuit being connected to the signal isolation circuit and being used to convert the external signal into a level digital signal; a control unit for controlling the on and off of the logic control circuit and the duty cycle of the level digital signal to determine the signal type of the external signal, and controlling the on and off of the fill light according to the signal type of the external signal. The circuit has the characteristics of low cost, high reliability and strong applicability, can effectively solve the problem of incompatibility between the existing fill light and the trigger signal of the camera device, and greatly facilitates the use of users.

Description

Technical Field

[0001] The present invention relates to the technical field of camera equipment, and in particular to an adaptive detection circuit for a fill light trigger signal. Background Art

[0002] In actual application, existing fill lights need to be triggered synchronously with the camera equipment to provide sufficient shooting brightness for the camera. There are many types of trigger signals for existing cameras, including switch quantities and level quantities, so fill lights are required to be synchronized with different trigger signals.

[0003] At present, most manufacturers need to confirm the type of trigger signal before the fill lights are shipped out of the factory, and then provide fill lights with corresponding trigger signal types. However, some projects require fill lights with different trigger signal types from multiple manufacturers.

[0004] If the fill light is not compatible with the trigger signals of cameras from different manufacturers, the procurement, supply, and on-site installation and debugging of the fill light will be extremely troublesome.

[0005] In the process of implementing the present invention, the inventors found that the related technology has the following problems: in the existing mainstream cameras, there are two triggering modes: switch quantity and level quantity, among which the level quantity also has 3.3V, 5V and 12V, etc. The signal triggering modes of the fill light of different manufacturers are different, so there is often a problem of mismatch between the signal of the fill light and the camera equipment. At the same time, some of the trigger input signals of the fill light are not isolated, and there is a possibility of being damaged by static electricity or interference voltage. Summary of the invention

[0006] The embodiment of the present invention provides an adaptive detection circuit for a fill light trigger signal, which is used to solve the problem of mismatching signals between the existing fill light and the camera device.

[0007] A first aspect of an embodiment of the present invention provides an adaptive detection circuit for a fill light trigger signal, comprising:

[0008] Signal isolation circuit, used to isolate the input external signal;

[0009] A logic control circuit, connected to the signal isolation circuit, for converting the external signal into a level digital signal;

[0010] a control unit, used for controlling the on-off of the logic control circuit and the duty cycle of the level digital signal to determine the signal type of the external signal, and;

[0011] According to the signal type of the external signal, the fill light is controlled to be turned on and off.

[0012] Optionally, the signal isolation circuit converts the external signal into an optical signal through an optical coupler, and converts the optical signal into the level digital signal.

[0013] Optionally, the signal isolation circuit further includes a surge protector and a switching diode for protecting the logic control circuit and the control unit.

[0014] Optionally, the adaptive detection circuit includes two input signal lines derived from the signal isolation circuit; the input signal lines can reuse the switching quantity and level quantity trigger signals and have the same positive and negative polarity wiring mode.

[0015] Optionally, the control unit is specifically configured to filter invalid external signals through a duty cycle of the level digital signal.

[0016] Optionally, the control unit includes: a first optical coupler, a first resistor, a second resistor, a third resistor and a single chip microcomputer;

[0017] The input end of the first optocoupler is connected to the first DC voltage and the first resistor respectively; the output end of the first optocoupler is connected to the second DC voltage and the output port of the microcontroller respectively through the second resistor; the third resistor is connected between the second DC voltage and the output port of the microcontroller.

[0018] Optionally, the signal isolation circuit further includes: a fourth resistor, a fifth resistor and a second optical coupler;

[0019] The input signal lines are respectively connected to the surge protectors; the fourth resistor is connected between the two input signal lines, and the switch diode is connected to the input signal line through the fifth resistor;

[0020] The input end of the second optical coupler is connected to the fifth resistor and the ground respectively; the two input signal lines are connected to the fifth resistor and the ground respectively.

[0021] Optionally, the logic control circuit includes: a sixth resistor; the output end of the second optocoupler is connected to the second DC voltage and to the ground through the sixth resistor respectively; and the input port of the single-chip microcomputer is connected to the output end of the second optocoupler.

[0022] Optionally, the control unit is specifically configured to control the indicator light to display an indication corresponding to the signal type according to the signal type of the external signal.

[0023] The adaptive detection circuit of the fill light trigger signal provided by the embodiment of the present invention has the characteristics of low cost, high reliability and strong applicability, can effectively solve the problem of incompatibility between the existing fill light and the camera device trigger signal, and greatly facilitates user use.

[0024] The above description is only an overview of the technical solution of the embodiment of the present invention. In order to more clearly understand the technical means of the embodiment of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the embodiment of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0026] Figure 1 is a schematic diagram of an adaptive detection circuit provided by an embodiment of the present invention;

[0027] Figure 2 It is a schematic diagram of a signal type determination method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0030] Figure 1 FIG. 1 is a schematic diagram of an adaptive detection circuit provided by an embodiment of the present invention. Figure 1 As shown, the adaptive detection circuit may include the following three parts: a signal isolation circuit 100 , a logic control circuit 200 and a control unit 300 .

[0031] The signal isolation circuit 100 is used to isolate the input external signal. The signal isolation circuit 100 may be a circuit for isolating the external signal through photoelectric isolation. Specifically, it may convert the external signal into an optical signal through an optical coupler, and convert the optical signal into the level digital signal, thereby isolating the external signal from the internal electrical components.

[0032] In some embodiments, the signal isolation circuit may further include a surge protector and a switching diode, etc., for protecting the logic control circuit and the control unit, and providing functions such as lightning protection and anti-static electricity.

[0033] The logic control circuit 200 is connected to the signal isolation circuit 100 and is used to convert the external signal into a level digital signal.

[0034] The control unit 300 is used to control the on and off of the logic control circuit and the duty cycle of the level digital signal to determine the signal type of the external signal, and control the on and off of the fill light according to the signal type of the external signal.

[0035] Specifically, the control unit 300 can be used to filter invalid external signals through the duty cycle of the level digital signal. For example, a suitable threshold can be preset according to the specification of the output signal of the camera device. When the duty cycle reaches a specific threshold, the level digital signal is determined to be an invalid interference signal.

[0036] Preferably, the control unit 300 may also be used to control the indicator light to display an indication corresponding to the signal type according to the signal type of the external signal.

[0037] Please continue reading Figure 1 The adaptive detection circuit may specifically include: a first optocoupler U1, a second optocoupler U2, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a surge protector U3, a switching diode U4 and a single-chip microcomputer.

[0038] The two input terminals (4, 3) of the first optical coupler U1 are respectively connected to the first DC voltage VCC1 and the first resistor R1. The two output terminals (1, 2) of the first optical coupler U1 are respectively connected to the second DC voltage VCC2 and the output port P / K of the single-chip computer through the second resistor R2. The third resistor R3 is connected between the second DC voltage VCC2 and the output port P / K of the single-chip computer.

[0039] Specifically, the first DC voltage VCC1 and the second DC voltage VCC2 can be set to appropriate voltage values ​​according to actual needs. For example, VCC1 can be set to 12V, and VCC2 can be set to 5V.

[0040] Furthermore, the adaptive detection circuit leads to two input signal lines (+, -) respectively connected to the surge protector U3. The fourth resistor R4 is connected in parallel with the surge protector and is also connected between the two input signal lines. The switch diode U4 is connected to the input signal line + through the fifth resistor R5.

[0041] The output terminal 3 of the first optical coupler U1 is connected to the input signal line + through the first resistor R1. The input terminal (1, 2) of the second optical coupler U2 is connected to the fifth resistor R5 and the ground respectively, and the two input signal lines (+, -) are also connected to the fifth resistor R5 and the ground respectively, serving as the input part of the second optical coupler U2.

[0042] The output terminal (4, 3) of the second optical coupler is connected to the second DC voltage VCC2 and the ground through the sixth resistor R6. The input port F_IN of the single chip microcomputer is connected to the output terminal 4 of the second optical coupler U2. The output terminal 3 of the second optical coupler U2 is connected to the ground.

[0043] like Figure 1 As shown, the adaptive detection circuit provided by the embodiment of the present invention has two input signal lines led out from the signal isolation circuit.

[0044] Through the above-mentioned adaptive detection circuit, the input signal line can reuse the light-on quantity and level quantity trigger signal, and has the same positive and negative polarity wiring method, so as to facilitate the use and debugging of the fill light in actual application.

[0045] In addition, the voltage range of the level signal that can be input into the signal input line is 3 to 12V, which can meet the output interface requirements of existing camera equipment.

[0046] The adaptive detection circuit provided in the embodiment of the present invention can confirm the specific signal type of the external signal through the duty cycle and signal logic, and flexibly set it to the corresponding trigger mode accordingly, so that the flash can achieve signal compatibility with the camera device.

[0047] Figure 2 The method for confirming the type of external signal provided by the embodiment of the present invention is as follows: Figure 2 As shown, the signal type confirmation process includes the following steps:

[0048] 210: Control the output terminal of the first optical coupler U1 to be disconnected, and detect whether F_IN has an input signal. If there is an input signal, execute step 220; if there is no input signal, execute step 230.

[0049] 220: The signal type is preliminarily determined to be a level signal.

[0050] 230: The signal type is preliminarily determined to be a switch signal.

[0051] 240: Control the output terminal of the first optical coupler U1 to conduct, and detect whether the input signal state of F_IN changes. If F_IN changes from a state of no input signal to a state of signal input, execute step 251. If F_IN still has an input signal, execute step 252; if F_IN still has no input signal, execute step 253.

[0052] 251: Determine the signal type as a switch signal.

[0053] 252: Determine that the signal type is a level signal.

[0054] 253: Determined to be a bad connection or no external signal.

[0055] 260: Perform duty cycle analysis on the detected input signal to determine whether the duty cycle of the input signal is greater than 50%. If so, return to step 210; if not, determine the signal type of the input signal.

[0056] 270: Control the on and off of the second optical coupler according to the signal type.

[0057] When the signal type is a switch signal, the second optical coupler is turned on, and when the signal type is a level signal, the second optical coupler is turned off to realize signal detection, achieve an adaptive effect, and realize perfect synchronization between the opening and closing of the fill light and the input signal of the camera device.

[0058] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0059] Similarly, it should be understood that in order to streamline the present invention and aid in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of the present invention, the various features of the embodiments of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. However, this disclosed method should not be interpreted as reflecting the following intention: that the claimed invention requires more features than the features explicitly recited in each claim. More specifically, as reflected in the claims below, inventive aspects lie in less than all the features of the individual embodiments disclosed above. Therefore, the claims that follow the specific embodiment are hereby expressly incorporated into the specific embodiment, with each claim itself serving as a separate embodiment of the present invention.

[0060] Those skilled in the art will appreciate that the modules in the devices in the embodiments may be adaptively changed and arranged in one or more devices different from the embodiments. The modules or units or components in the embodiments may be combined into one module or unit or component, and in addition they may be divided into a plurality of submodules or subunits or subcomponents. Except that at least some of such features and / or processes or units are mutually exclusive, all features disclosed in this specification (including the accompanying claims, abstracts and drawings) and all processes or units of any method or device disclosed in this manner may be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstracts and drawings) may be replaced by an alternative feature providing the same, equivalent or similar purpose.

[0061] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. An adaptive detection circuit for a fill light trigger signal, characterized in that: include: A single chip microcomputer, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a first optical coupler U1, a second optical coupler U2, a surge protector U3 and a switching diode U4, wherein an output port P / K of the single chip microcomputer is connected to one end of the third resistor R3 and a pin 2 of the first optical coupler U1, the other end of the third resistor R3 is connected to one end of the second resistor R2 and is connected to a second DC voltage VCC2, the other end of the second resistor R2 is connected to a pin 1 of the first optical coupler U1, a pin 4 of the first optical coupler U1 is connected to the first DC voltage VCC1, a pin 3 of the first optical coupler U1 is connected to one end of the first resistor R1, the other end of the first resistor R1 is connected to one end of the fourth resistor R4, a fifth resistor R5 One end of the fifth resistor R5 is connected to one end of the surge protector U3 and leads to a positive input signal line, the other end of the fifth resistor R5 is connected to pin 1 of the second optical coupler U2 and the center point of the switching diode U4, the cathode of the switching diode U4 is connected to the first DC voltage VCC1, the anode of the switching diode U4 is grounded, the pin 2 of the second optical coupler U2 is connected to the other end of the fourth resistor R4 and the other end of the surge protector U3 and grounded, and leads to a negative input signal line, the pin 4 of the second optical coupler U2 is connected to one end of the sixth resistor R6 and connected to the input port F_IN of the single-chip computer, the other end of the sixth resistor R6 is connected to the second DC voltage VCC2, and the pin 3 of the second optical coupler U2 is grounded; the positive input signal line and the negative input signal line are connected to the external signal from the camera device; Pin 1 of the first optocoupler U1 and the second optocoupler U2 is the LED anode, pin 2 is the LED cathode, pin 3 is the emitter of the photodetector, and pin 4 is the collector of the photodetector; the switching diode U4 is composed of two diodes connected, wherein the anode of the first diode serves as the anode of the switching diode U4, the cathode of the first diode is connected to the anode of the second diode as the center point of the switching diode U4, and the cathode of the second diode serves as the cathode of the switching diode U4; The signal isolation circuit includes a second optical coupler U2, a switching diode U4, a fourth resistor R4, a fifth resistor R5 and a surge protector U3. The second optical coupler U2 converts the external signal into an optical signal, and converts the optical signal into a level digital signal, thereby isolating the external signal from the internal electrical components. The logic control circuit includes a first resistor R1, a second resistor R2, a third resistor R3 and a first optical coupler U1, and the logic control circuit is connected to the signal isolation circuit and is used to convert the external signal into a level digital signal; The control unit includes a single chip microcomputer, which is used to control the on and off of the logic control circuit and determine the signal type of the external signal through the duty cycle of the level digital signal; The control unit controls the fill light to be turned on and off synchronously according to the signal type of the external signal.

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