control device for fill lights

Abstract

This invention provides a control device for a supplementary light. Based on this application, the control device utilizes a signal sampling circuit to sample a brightness sensing component, obtaining a sampling voltage signal representing the ambient brightness. Furthermore, it can generate a switching logic signal to indicate the start or stop of the supplementary light's LED module by comparing the sampling voltage signal with a threshold voltage. In addition, the control device includes a hysteresis control circuit. This hysteresis circuit adjusts the adjustable resistance value upon which the signal sampling circuit generates the sampling voltage signal based on the switching logic signal. This suppresses the voltage increment of the sampling voltage signal caused by the supplementary light brightness when the LED module starts up, thereby creating a hysteresis constraint to suppress supplementary light brightness interference during the switching process from start to stop of the LED module. This, in turn, suppresses flickering of the supplementary light when the ambient brightness changes.

Description

Technical Field

[0001] This invention relates to supplementary lighting technology, and particularly to a control device for a supplementary lighting lamp, a supplementary lighting lamp using the control device, and a camera using the supplementary lighting lamp. Background Technology

[0002] For cameras deployed in outdoor environments, ambient brightness can vary significantly due to changes in sunlight conditions caused by factors such as day-night cycles or weather variations. Therefore, such cameras are typically equipped with supplemental lighting. Supplemental lighting includes an LED module, which may include LEDs (Light Emitting Diodes). The supplemental lighting also includes a control device that detects ambient brightness and adaptively activates or deactivates the LED module in response to changes in detected ambient brightness. Specifically, the LED module can adaptively activate in response to low ambient brightness caused by weakened sunlight (e.g., cloudy / rainy weather) or complete absence of sunlight (e.g., day / night cycle) to improve image quality when the camera's field of view is low by supplementing illumination. Conversely, the LED module can adaptively deactivate in response to the restoration of sunlight and the attainment of adequate ambient brightness to prevent overexposure when the ambient brightness is sufficient, thus improving image quality when the ambient brightness is adequate.

[0003] However, ambient brightness is often affected by other light sources besides sunlight. For example, the brightness produced by supplementary lighting is a type of interference with ambient brightness.

[0004] That is, when the control device adaptively starts due to the low ambient brightness detected, the supplementary light generated by the LED module causes the ambient brightness detected by the control device to reach the standard. As a result, the LED module that has just started will be turned off again because the ambient brightness reaches the standard. If the process of the LED module being turned off immediately after starting is repeated, it will cause the supplementary light to flicker.

[0005] Conversely, when the control device adaptively shuts down because it detects that the ambient brightness of the supplementary light is sufficient, the ambient brightness detected by the control device becomes too low due to the sudden disappearance of the supplementary light. As a result, the LED module that was just shut down will be shut down again due to the low ambient brightness. Furthermore, if the LED module is repeatedly shut down and then immediately restarted, it will also cause the supplementary light to flicker.

[0006] The aforementioned flicker not only fails to improve the image quality of the camera, but also causes light pollution.

[0007] It is evident that how to suppress the flicker of supplementary lights when the ambient brightness changes has become a technical problem that needs to be solved in the existing technology. Summary of the Invention

[0008] The technical solutions provided by the embodiments of the present invention help to suppress the flickering of supplementary lights when the ambient brightness changes.

[0009] In one embodiment of this application, a control device for a fill light includes:

[0010] A brightness sensing component is used to generate a photocurrent signal based on the sensed ambient brightness, and the current value of the photocurrent signal is associated with the ambient brightness;

[0011] A signal sampling circuit is used to generate a sampling voltage signal based on the photocurrent signal. The voltage value of the sampling voltage signal is proportional to the current value of the photocurrent signal. The proportionality coefficient between the voltage value of the sampling voltage signal and the current value of the photocurrent signal is an adjustable resistance value. Furthermore, the voltage value of the sampling voltage signal is used as a brightness sampling value to characterize the ambient brightness.

[0012] A logic determination circuit is used to generate a switching logic signal based on the comparison result between the voltage value of the sampled voltage signal and a threshold voltage. The threshold voltage is used to characterize a brightness threshold, which is a switching condition between the start and stop of the LED module of the supplementary light. The level state of the switching logic signal is set to an effective level state to indicate the start of the LED module when the voltage value of the sampled voltage signal is lower than the threshold voltage, and the level state of the switching logic signal is set to an invalid level state to indicate the stop of the LED module when the voltage value of the sampled voltage signal is higher than or equal to the threshold voltage.

[0013] A hysteresis control circuit is used to adjust the adjustable resistor value based on the switching logic signal, wherein adjusting the adjustable resistor value includes:

[0014] When the switch logic signal is at an active level, the adjustable resistor value is reduced from a first resistance value to a second resistance value to suppress the voltage value increment of the sampled voltage signal caused by the supplementary light brightness generated by the lamp module when the lamp module is started.

[0015] When the switch logic signal is in an invalid level state, the adjustable resistor value is raised from the second resistance value to the first resistance value, so as to remove the suppression of the voltage value of the sampled voltage signal when the lamp module is turned off.

[0016] In some examples, optionally, the signal sampling circuit includes a sampling resistor, and the first resistance value is the resistance value of the sampling resistor; the hysteresis control circuit includes a compensation resistor, and the second resistance value is the equivalent resistance value when the sampling resistor and the compensation resistor are connected in parallel; the hysteresis control circuit is specifically used to: enable the parallel connection of the compensation resistor and the sampling resistor when the switch logic signal is at an active level; and deactivate the parallel connection of the compensation resistor and the sampling resistor when the switch logic signal is at an inactive level.

[0017] In some examples, optionally, the signal sampling circuit includes a current receiving terminal for receiving the photocurrent signal and a voltage output terminal for generating the sampled voltage signal. The sampling resistor is connected in series in a fixed current loop between the voltage output terminal and ground, and the fixed current loop is connected to the current receiving terminal. The compensation resistor is connected in series in a controllable current loop between the voltage output terminal and ground, and the controllable current loop is connected to the current receiving terminal. Furthermore, the controllable current loop is connected in parallel with the fixed current loop. The hysteresis control circuit is specifically used to: turn on the controllable current loop when the switch logic signal is at an active level to enable the parallel connection of the compensation resistor and the sampling resistor; and turn off the controllable current loop when the switch logic signal is at an inactive level to cancel the parallel connection of the compensation resistor and the sampling resistor.

[0018] In some examples, the hysteresis control circuit may optionally further include a first switching element connected in series with the compensation resistor in the controllable current loop, wherein: when the switching logic signal is at an active level, the first switching element is set to a closed state that turns on the controllable current loop; and when the switching logic signal is at an inactive level, the first switching element is set to an open state that turns off the controllable current loop.

[0019] In some examples, optionally, the preset brightness drop is proportional to the threshold voltage, the preset brightness drop is inversely proportional to the brightness threshold, and the preset brightness drop is proportional to the difference between the reciprocal of the second resistance value and the reciprocal of the first resistance value.

[0020] In some examples, optionally, the effective level state of the digital level signal is low, and the invalid level state of the digital level signal is high; the logic determination circuit includes an OR gate, a NAND gate, and an AND gate, wherein: the two inputs of the OR gate respectively receive the digital level signal and a continuously high reference level signal; the two inputs of the NAND gate respectively receive the digital level signal and the reference level signal; the two inputs of the AND gate are respectively connected to the output signals of the OR gate and the NAND gate, and the output signal of the AND gate is the switching logic signal; the effective level state of the switching logic signal is high, and the invalid level state of the switching logic signal is low.

[0021] Optionally, in some examples, a signal processing circuit is further included to generate a digital level signal based on the sampled voltage signal, wherein the level state of the digital level signal is used to characterize the comparison result between the voltage value of the sampled voltage signal and the threshold voltage; the logic determination circuit is specifically used to generate the switching logic signal based on the digital level signal, wherein: when the level state of the digital level signal is an effective level state characterizing that the brightness sample value is lower than the brightness threshold, the level state of the switching logic signal is an effective level state for activating the LED module; when the level state of the digital level signal is an invalid level state characterizing that the brightness sample value is higher than or equal to the brightness threshold, the level state of the switching logic signal is an invalid level state for deactivating the LED module.

[0022] In some examples, the signal processing circuit may optionally include a second switching element whose cutoff voltage is associated with the threshold voltage, wherein: when the voltage value of the sampled voltage signal is lower than the threshold voltage, the second switching element is closed, and the level state of the digital level signal is set to an effective level state indicating that the luminance sample value is lower than the luminance threshold due to the closure of the second switching element; when the voltage value of the sampled voltage signal is lower than the threshold voltage, the second switching element is open, and the level state of the digital level signal is set to an invalid level state indicating that the luminance sample value is higher than or equal to the luminance threshold due to the openness of the second switching element.

[0023] In some examples, the circuit may optionally include an LED driver circuit for generating a constant current drive output that causes the LED module to produce supplemental lighting brightness when the switch logic signal is at an active level, and for stopping the constant current drive output to the LED module when the switch logic signal is at an inactive level.

[0024] In another embodiment of this application, another control device for a supplementary light includes:

[0025] A brightness sensing component is used to generate a photocurrent signal based on the sensed ambient brightness, and the current value of the photocurrent signal is associated with the ambient brightness;

[0026] A signal sampling circuit is used to generate a sampling voltage signal based on the photocurrent signal. The voltage value of the sampling voltage signal is proportional to the current value of the photocurrent signal. The voltage value of the sampling voltage signal is used to characterize the ambient brightness as a brightness sampling value. The comparison result between the voltage value of the sampling voltage signal and a threshold voltage characterizing the brightness threshold is used to determine the state of the LED module of the supplementary light. Furthermore, the proportionality coefficient between the voltage value of the sampling voltage signal and the current value of the photocurrent signal is an adjustable resistance value.

[0027] Hysteresis control circuit, used for:

[0028] When the LED module is in the off state, the adjustable resistor value is adjusted to the first resistance value;

[0029] When the LED module is in the start state, the adjustable resistor value is adjusted to the second resistance value;

[0030] The first resistance value is greater than the second resistance value, so that when the ambient brightness is at the same brightness value within the brightness range equal to or higher than the brightness threshold, the sampling voltage signal will have a first voltage value and a second voltage value lower than the first voltage value when the state of the lamp module is the off state and the on state, respectively.

[0031] The first voltage value represents the first brightness sample value, which is matched with the current true brightness value of the ambient brightness, so that the lamp module switches from the off state to the on state and is triggered in response to the current true brightness value of the ambient brightness dropping below the brightness threshold.

[0032] The second voltage value represents a second brightness sample value that is lower than the first brightness sample value. The second brightness sample value has a brightness drop compared to the current true brightness value of the ambient brightness. The brightness drop is used to trigger the lamp module to switch from the start state to the off state for the light-off operation. It has a hysteresis at the time when the current true brightness value of the ambient brightness rises to be equal to or higher than the brightness threshold.

[0033] In some examples, optionally, the signal sampling circuit includes a sampling resistor, and the hysteresis control circuit includes a compensation resistor; the first resistance value is the resistance value of the sampling resistor, and the second resistance value is the equivalent resistance value when the sampling resistor and the compensation resistor are connected in parallel; the hysteresis control circuit is specifically used to: enable the parallel connection of the compensation resistor and the sampling resistor when the LED module is in the start-up state; and deactivate the parallel connection of the compensation resistor and the sampling resistor when the LED module is in the off state.

[0034] Optionally, in some examples, a logic determination circuit is further included to generate a switching logic signal based on a comparison between the voltage value of the sampled voltage signal and a threshold voltage, wherein the threshold voltage is used to characterize a brightness threshold, which is a switching condition between the activation and deactivation of the LED module of the supplementary light; the level state of the switching logic signal is set to an effective level state for activating the LED module when the voltage value of the sampled voltage signal is lower than the threshold voltage, and the level state of the switching logic signal is set to an ineffective level state for deactivating the LED module when the voltage value of the sampled voltage signal is higher than or equal to the threshold voltage; the state of the LED module is indicated by the level state of the switching logic signal, and the hysteresis control circuit is controlled by the level state of the switching logic signal.

[0035] In another embodiment of this application, a supplementary light includes the control device and the lamp module described in the foregoing embodiments.

[0036] In another embodiment of this application, a camera includes an optical imaging component and the fill light from the foregoing embodiments.

[0037] In another embodiment of this application, a supplementary lighting control method includes:

[0038] Acquire a photocurrent signal, which includes a first photocurrent signal or a second photocurrent signal. The first photocurrent signal is obtained based on a first ambient brightness during the process of the ambient light brightness in the monitoring area changing from strong to weak when the LED module of the supplementary light is turned off. The second photocurrent signal is obtained based on a second ambient brightness during the process of the ambient light brightness in the monitoring area changing from weak to strong when the LED assembly of the supplementary light is turned on. Furthermore, the brightness values ​​of the first ambient brightness and the second ambient brightness are the same.

[0039] The acquired photocurrent signal is input to a preset signal sampling circuit, wherein the signal sampling circuit is configured to generate a sampling voltage signal based on the photocurrent signal and the equivalent sampling resistance;

[0040] Based on the comparison result between the sampled voltage signal and the threshold voltage, the LED module is controlled to turn on and off, wherein:

[0041] The equivalent sampling resistance value is a first resistance value when the lamp module is turned off, so that the sampling voltage signal obtained based on the first photocurrent signal has a first voltage value for characterizing the first ambient brightness.

[0042] The equivalent sampling resistance value is the second resistance value when the lamp module is turned on, so that the sampling voltage signal obtained based on the second photocurrent signal has a second voltage value for characterizing the second ambient brightness.

[0043] Wherein, the first resistance value is greater than the second resistance value, and the first voltage value is greater than the second voltage value, so that the lamp module is turned on when the first voltage value is less than the threshold voltage and turned off when the second voltage value is greater than the threshold voltage.

[0044] Based on the above embodiments, the control device for the supplementary light utilizes a signal sampling circuit to sample the brightness sensing component, obtaining a sampling voltage signal representing the ambient brightness. Furthermore, by comparing the sampling voltage signal with a threshold voltage, a switching logic signal is generated to indicate whether the LED module of the supplementary light is activated or deactivated, supporting adaptive activation and deactivation of the LED module in response to changes in ambient brightness. In addition, the control device includes a hysteresis control circuit. This hysteresis circuit adjusts the adjustable resistance value upon which the signal sampling circuit generates the sampling voltage signal based on the switching logic signal. This suppresses the voltage increment of the sampling voltage signal caused by the supplementary light brightness when the LED module is activated. Furthermore, suppressing this voltage increment ensures that the brightness sampling value represented by the sampling voltage signal has a preset brightness drop below the ambient brightness when the LED module is activated. The preset brightness difference is used as an additional condition to determine whether to turn off the LED module when it is started, so as to form a hysteresis constraint on the switching process of the LED module from start to stop to suppress the interference of the supplementary light brightness, thereby suppressing the flicker of the supplementary light when the ambient brightness changes. Attached Figure Description

[0045] The following figures are for illustrative and explanatory purposes only and do not limit the scope of the invention:

[0046] Figure 1 This is an exemplary structural diagram of the control device for the supplementary lighting in the embodiments of this application;

[0047] Figure 2 For example Figure 1 A schematic diagram of the photoelectric linear relationship of the brightness sensing component in the control device shown.

[0048] Figure 3 For example Figure 1 A schematic diagram of an example structure of the signal sampling circuit and hysteresis control circuit in the control device shown.

[0049] Figure 4 For example Figure 1 A schematic diagram of the hysteresis constraint principle of the hysteresis control circuit in the control device shown.

[0050] Figure 5 For example Figure 1 A schematic diagram of a preferred structure of the control device is shown;

[0051] Figure 6 For example Figure 5 The diagram shows an example of the signal processing circuit and logic decision circuit in the control device. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0053] Figure 1 This is an exemplary structural diagram of the control device for the supplementary lighting in an embodiment of this application. Please refer to... Figure 1 In one embodiment of this application, the control device for the supplementary light may include a brightness sensing component 10, a signal sampling circuit 20, a logic determination circuit 60, and a hysteresis control circuit 30.

[0054] The brightness sensing component 10 is used to generate a photocurrent signal I_sen based on the ambient brightness of the environment where the fill light is located, and the current value of the photocurrent signal I_sen is related to the ambient brightness of the environment where the fill light is located.

[0055] For example, the brightness sensing component 10 may include a photodiode, the photodiode's operating voltage Vcc1 may be 5V, the photodiode may also have a current output pin, and the current output pin may generate a photocurrent signal I_sen.

[0056] Figure 2 For example Figure 1 A schematic diagram illustrating the photoelectric linear relationship of the brightness sensing component in the control device shown. (See diagram for example.) Figure 2As shown, the current value of the photocurrent signal I_sen generated by the brightness sensing component 10 can be linearly related to the ambient brightness it senses (i.e., the ambient brightness of the environment where the supplementary light is located). If W_env represents the ambient brightness sensed by the brightness sensing component 10, then the linear relationship between the current value of the photocurrent signal I_sen generated by the brightness sensing component 10 and the ambient brightness W_env it senses can be expressed as the following expression (1):

[0057] I_sen=k×W_env expression(1)

[0058] In expression (1), k is a linear coefficient, and the value of k is determined by the electrical characteristics of the photodiode included in the brightness sensing component 10. For example, k can be 0.5. In expression (1), the unit of ambient brightness W_env is lux (lumen).

[0059] The signal sampling circuit 20 is used to generate a sampling voltage signal U_sen based on the photocurrent signal I_sen. The voltage value of the sampling voltage signal U_sen is proportional to the current value of the photocurrent signal I_sen. The proportionality coefficient between the voltage value of the sampling voltage signal U_sen and the current value of the photocurrent signal I_sen is an adjustable resistance value R_adj. Furthermore, the voltage value of the sampling voltage signal U_sen is used to characterize the brightness sampling value W_sp of the ambient brightness W_env.

[0060] Figure 3 For example Figure 1 The diagram shows an example of the signal sampling circuit and hysteresis control circuit in the control device. Please refer to [link / reference]. Figure 3 :

[0061] The signal sampling circuit 20 may include a sampling resistor R_sp that receives the photocurrent signal I_sen and a voltage output terminal that generates the sampling voltage signal U_sen. The sampling resistor R_sp is connected in series in the solidified current loop between the voltage output terminal of the signal sampling circuit 20 and ground. The solidified current loop is connected to the current receiving terminal of the signal sampling circuit 20.

[0062] A compensation resistor R_cp is connected in series in the controllable current loop between the voltage output terminal of the signal sampling circuit 20 and ground. This controllable current loop is connected to the current receiving terminal of the signal sampling circuit 20, and the controllable current loop containing the compensation resistor R_cp is connected in parallel with the sampling resistor R_sp.

[0063] Among them, the solidified current loop is a normally closed loop, and the conduction state of the controllable current loop is controlled by the hysteresis control circuit 30. Therefore, based on such Figure 3 The example structure shown:

[0064] When the controllable current loop containing the compensation resistor R_cp is disconnected, the aforementioned adjustable resistance value R_adj can be the first resistance value, which is the resistance value of the sampling resistor R_sp.

[0065] When the controllable current loop containing the compensation resistor R_cp is turned on, the aforementioned adjustable resistance value R_adj can be a second resistance value, which is the equivalent resistance value R_sp×R_cp / (R_sp+R_cp) when the sampling resistor R_sp and the compensation resistor R_cp are connected in parallel.

[0066] That is, the adjustable resistance value R_adj can be regarded as the equivalent sampling resistance value of the signal sampling circuit 20. In particular, the sampling resistor R_sp and the compensation resistor R_cp can both be high-precision resistors, for example, high-precision resistors with a resistance accuracy of 1%.

[0067] In addition, from Figure 3 As can be seen from the diagram, the signal sampling circuit 20 may also include a decoupling voltage regulator capacitor C20 connected in parallel with the sampling resistor R_sp, and a current limiting resistor R20 connected in series with the voltage output terminal.

[0068] In the embodiments of this application, the sampling voltage signal U_sen generated by the signal sampling circuit 20 can be used to determine the state of the LED module 80 of the supplementary light, specifically:

[0069] The logic determination circuit 60 is used to generate a switching logic signal S_ctr based on the comparison result Comp{U_sen,U_ref} between the voltage value of the sampled voltage signal U_sen and the threshold voltage U_ref. The threshold voltage U_ref is used to characterize the brightness threshold W_ref, and the brightness threshold W_ref is the switching condition between the start and stop of the LED module 80 of the supplementary light. Specifically:

[0070] When the voltage value of the sampled voltage signal U_sen is lower than the threshold voltage U_ref, the level of the switching logic signal S_ctr is set to the effective level state for starting the lamp module 80.

[0071] When the voltage value of the sampled voltage signal U_sen is higher than or equal to the threshold voltage U_ref, the level state of the switch logic signal S_ctr is set to an invalid level state for turning off the lamp module 80.

[0072] Among them, the sampling voltage signal U_sen can be a digital signal, the effective level state of the switch logic signal S_ctr can be a high level state that is at the same potential as the working voltage Vcc6 (e.g., 5V) of the logic determination circuit 60, and the ineffective level state of the switch logic signal S_ctr can be a ground level state that is at the same potential as ground.

[0073] In the embodiments of this application, the switching logic signal S_ctr used to turn the indicator light bead module 80 on or off can be sent to the light bead driving circuit 70. The light bead driving circuit 70 is used to generate a constant current drive output I_drv that causes the light bead module 80 to generate supplementary light brightness when the switching logic signal S_ctr is in an active level state, and to stop the constant current drive output I_drv to the light bead module 80 when the switching logic signal S_ctr is in an inactive level state.

[0074] The hysteresis control circuit 30 is used to adjust the adjustable resistance value R_adj based on the switching logic signal S_ctr (i.e., the state of the LED module 80 of the fill light). Specifically, the hysteresis circuit 30 is controlled by the level state of the switching logic signal S_ctr (i.e., the state of the LED module 80 of the fill light). The adjustment of the adjustable resistance value R_adj by the hysteresis control circuit 30 includes:

[0075] When the switch logic signal S_ctr is in an invalid level state (i.e., the state of the lamp module 80 is off), the adjustable resistor value R_adj is adjusted to the first resistance value so that any brightness value (which can be called a high brightness value) of the ambient brightness W_env within the brightness range equal to or higher than the brightness threshold W_ref will trigger the sampling voltage signal U_sen to have the first voltage value when the state of the lamp module 80 is off.

[0076] When the switch logic signal S_ctr is in an active state (i.e., the state of the lamp module 80 is in the start state), the adjustable resistor value R_adj is adjusted to the second resistance value so that the same high brightness value of the ambient brightness W_env will trigger the sampling voltage signal U_sen to have a second voltage value when the state of the lamp module 80 is in the off state.

[0077] That is, since the first resistance value is greater than the second resistance value, for the same brightness value (i.e., the same high brightness value) within the brightness range of the ambient brightness W_env, which is equal to or higher than the brightness threshold W_ref, the sampling voltage signal U_sen will have a first voltage value and a second voltage value lower than the first voltage value when the LED module 80 is in the off state and the on state, respectively.

[0078] The first voltage value of the sampling voltage signal U_sen represents the first brightness sampling value, which is matched with the current real brightness value of the ambient brightness W_env (e.g., the aforementioned high brightness value) so that the lamp module 80 can switch from the off state to the on state and be triggered in response to the change in the current real brightness value of the ambient brightness W_env to be lower than the brightness threshold W_ref.

[0079] The second voltage value of the sampled voltage signal U_sen represents a second luminance sample value that is lower than the first luminance sample value, and this second luminance sample value has a luminance drop ΔW compared to the current true luminance value of the ambient luminance W_env.

[0080] In the embodiments of this application, the preset brightness drop ΔW is directly proportional to the threshold voltage U_ref, inversely proportional to the brightness threshold W_ref, and directly proportional to the difference between the reciprocal of the second resistance value and the reciprocal of the first resistance value. For example, the relationship between the preset brightness drop ΔW and the threshold voltage U_ref, the brightness threshold W_ref, and the first and second resistance values ​​can be expressed as the following expression (2):

[0081]

[0082] The physical meaning of k in the above expression (2) is the same as that of k in the expression (1) described above.

[0083] The voltage value corresponding to the brightness difference ΔW can be approximately equivalent to: the voltage increment caused by the supplementary light brightness generated by the LED module 80 when the sampled voltage signal U_sen is in the activated state. Therefore, the existence of this brightness difference ΔW can be considered as the suppression of the voltage increment caused by the supplementary light brightness generated by the LED module 80. Therefore, the adjustment of the adjustable resistance value R_adj by the hysteresis control circuit 30 can also be considered as:

[0084] When the switching logic signal S_ctr is in an active state (i.e., the state of the lamp module 80 is in the start state), the adjustable resistor value R_adj is reduced from the first resistance value to the second resistance value to suppress the voltage increment of the sampling voltage signal U_sen caused by the supplementary light brightness generated by the lamp module 80 when the lamp module 80 is started.

[0085] When the switching logic signal S_ctr is in an invalid level state (i.e., the state of the lamp module 80 is off), the adjustable resistor value R_adj is raised from the aforementioned second resistance value to the aforementioned first resistance value, so as to remove the suppression of the voltage value of the sampled voltage signal U_sen when the lamp module 80 is off.

[0086] Based on the above embodiments, the control device of the supplementary light uses the signal sampling circuit 20 to sample the brightness sensing component 10, and can obtain a sampling voltage signal U_sp of the brightness sampling value W_sp used to characterize the ambient brightness W_env. Furthermore, based on the comparison result of the sampling voltage signal U_sp and the threshold voltage U_ref, the lamp bead module 80 of the supplementary light can be controlled to start or stop, so as to support the adaptive start and adaptive stop of the lamp bead module 80 in response to changes in ambient brightness W_env.

[0087] Based on this, the hysteresis control circuit 30 of the control device can adjust the adjustable resistance value R_adj on which the signal sampling circuit 20 relies to generate the sampling voltage signal U_sp according to the switching logic signal S_ctr, so as to suppress the voltage value increment of the sampling voltage signal U_sp caused by the supplementary light brightness when the lamp module 80 is started. Furthermore, the suppression of this voltage increment can make the brightness sampling value W_sp represented by the sampling voltage signal U_sp have a preset brightness drop ΔW lower than the ambient brightness when the lamp module 80 is started. This brightness drop ΔW is used to make the trigger time of the lamp module 80 switching from the start state to the off state have a hysteresis at the time when the current real brightness value of the ambient brightness W_env rises to be equal to or higher than the brightness threshold W_ref.

[0088] Figure 4 For example Figure 1 The diagram shows the hysteresis constraint principle of the hysteresis control circuit in the control device shown. (See...) Figure 4 In this example, the effective level of the switch logic signal S_ctr is a high level state, which is at the same potential as the operating voltage Vcc6 of the logic determination circuit 60, and the ineffective level state of the switch logic signal S_ctr can be a ground level state, which is at the same potential as ground. Furthermore:

[0089] The solid arrow line is used to characterize the process curve of the switching logic signal S_ctr switching from an invalid level state to an active level state in response to the decrease of ambient brightness W_env, that is, the start-up process curve of the LED module 80.

[0090] The dashed arrow line is used to characterize the process curve of the switching logic signal S_ctr switching from an active level state to an inactive level state in response to the increase of ambient brightness W_env, that is, the turning-off process curve of the LED module 80.

[0091] By comparison Figure 4 The startup and shutdown process curves show that:

[0092] When the switching logic signal S_ctr is in an invalid level state (i.e., the LED module 80 is started), the brightness sample value W_sp represented by the sampling voltage signal U_sp used by the logic determination circuit 60 to make a determination approaches the current real ambient brightness W_env. Under this condition, the decision condition that causes the switching logic signal S_ctr to switch from an invalid level state to an effective level state can be considered as the real ambient brightness W_env being lower than the reference brightness W_ref.

[0093] When the switching logic signal S_ctr is in an active state (i.e., the LED module 80 is started), the brightness sample value W_sp represented by the sampling voltage signal U_sp used by the logic determination circuit 60 has a preset brightness difference ΔW compared to the actual ambient brightness W_env. Under this condition, the decision condition that causes the switching logic signal S_ctr to switch from an active state to an inactive state can be considered as the sum of the actual ambient brightness W_env and the preset brightness difference ΔW being equal to or higher than the reference brightness W_ref.

[0094] As can be seen above, the preset brightness difference ΔW is used as an additional condition for determining whether to turn off the LED module 80 when it is started: for any brightness value of the ambient brightness W_env within the brightness range equal to or higher than the brightness threshold W_ref, it can trigger the LED module to turn on; however, the difference between it and the brightness threshold W_ref needs to reach the brightness difference ΔW before it can trigger the LED module to turn off. Thus, a hysteresis constraint is formed to suppress the interference of supplementary light brightness during the switching process of the LED module 80 from start-up to shutdown. This avoids the LED module from immediately turning off due to the sudden increase in supplementary light brightness introduced into the ambient brightness W_env after startup, and then starting again after turning off due to the disappearance of the supplementary light brightness introduced into the ambient brightness W_env. Furthermore, it can suppress the flicker of the supplementary light when the ambient brightness changes.

[0095] In the embodiments of this application, the aforementioned compensation resistor R_cp may be part of the hysteresis control circuit 30, that is, the hysteresis control circuit 30 includes the aforementioned compensation resistor R_cp, and in this case, please refer again to Figure 3 The hysteresis control circuit 30 can be specifically used for:

[0096] When the switching logic signal S_ctr is in an active state (i.e., the LED module 80 is started), the parallel connection of the compensation resistor R_cp and the sampling resistor R_sp is enabled, thereby causing the above-mentioned adjustable resistance value R_adj to be reduced to the second resistance value, that is, the equivalent resistance value when the sampling resistor R_sp and the compensation resistor R_cp are connected in parallel is R_sp×R_cp / (R_sp+R_cp).

[0097] When the switch logic signal S_ctr is in an invalid level state (i.e., the LED module 80 is off), the parallel connection between the compensation resistor R_cp and the sampling resistor R_sp is removed, thereby causing the aforementioned adjustable resistance value R_adj to be adjusted back to the first resistance value, that is, the resistance value of the sampling resistor R_sp.

[0098] For example, enabling and deactivating the parallel connection between the compensation resistor R_cp and the sampling resistor R_sp in the hysteresis control circuit 30 can be achieved by controlling the conduction and disconnection of the controllable current loop containing the compensation resistor R_cp, that is:

[0099] When the switching logic signal S_ctr is in an active state (i.e., the state of the lamp module 80 is the start state), the hysteresis control circuit 30 can turn on the controllable current loop where the compensation resistor R_cp is located, so as to enable the parallel connection of the compensation resistor R_cp and the sampling resistor R_sp.

[0100] When the switching logic signal S_ctr is in an invalid level state (i.e., the state of the lamp module 80 is off), the hysteresis control circuit 30 can disconnect the controllable current loop where the compensation resistor R_cp is located, so as to cancel the parallel connection between the compensation resistor R_cp and the sampling resistor R_sp.

[0101] See also Figure 3 To control the on / off state of the controllable current loop containing the compensation resistor R_cp, the hysteresis control circuit 30 may further include a first switching element QS30, which is connected in series with the compensation resistor R_cp in the aforementioned controllable current loop, and:

[0102] When the switching logic signal S_ctr is in an active state (i.e., the LED module 80 is started), the first switching element QS30 is set to a closed state that turns on the controllable current loop containing the compensation resistor R_cp.

[0103] When the switching logic signal S_ctr is in an invalid level state (i.e., the LED module 80 is off), the first switching element QS30 is set to an open state that disconnects the controllable current loop containing the compensation resistor R_cp.

[0104] For example, the first switching element QS30 may include a transistor. If the effective level of the switching logic signal S_ctr is a high level state that is at the same potential as the operating voltage Vcc6 (e.g., 5V) of the logic determination circuit 60, and the ineffective level state of the switching logic signal S_ctr is a ground level state that is at the same potential as ground, then the first switching element QS30 may include an NPN transistor.

[0105] Figure 5 For example Figure 1 A schematic diagram of a preferred structure of the control device is shown. Please refer to [link / reference]. Figure 5In the embodiments of this application, in order to determine the comparison result Comp{U_sen,U_ref} between the voltage value of the sampled voltage signal U_sen and the threshold voltage U_ref, so that the logic determination circuit 60 can generate the switching logic signal S_ctr, the control device of the supplementary light may further include a signal processing circuit 50.

[0106] The signal processing circuit 50 can be used to convert the sampled voltage signal U_sen (i.e., analog voltage signal) into a digital level signal S_dg. That is, the signal processing circuit 50 is used to generate a digital level signal S_dg based on the sampled voltage signal U_sen, and the level state of the digital level signal S_dg is used to characterize the comparison result Comp{U_sen,U_ref} between the voltage value of the sampled voltage signal U_sen and the threshold voltage U_ref.

[0107] That is, based on such Figure 5 The preferred structure shown is:

[0108] The brightness sensing component 10 is used to generate a photocurrent signal I_sen based on the sensed ambient brightness W_env, and the current value of the photocurrent signal I_sen is associated with the ambient brightness W_env;

[0109] The signal sampling circuit 20 is used to generate a sampling voltage signal U_sen based on the photocurrent signal I_sen. The voltage value of the sampling voltage signal U_sen is proportional to the current value of the photocurrent signal I_sen. The proportionality coefficient between the voltage value of the sampling voltage signal U_sen and the current value of the photocurrent signal I_sen is an adjustable resistance value. Furthermore, the voltage value of the sampling voltage signal U_sen is used to characterize the brightness sampling value W_sp of the ambient brightness W_env.

[0110] The signal processing circuit 50 is used to generate a digital level signal based on the sampled voltage signal U_sen. The level state of the digital level signal S_dg is set to an active level state when the voltage value of the sampled voltage signal U_sen is lower than the threshold voltage U_ref, and the level state of the digital level signal S_dg is set to an inactive level state when the voltage value of the sampled voltage signal U_sen is higher than or equal to the threshold voltage U_ref. The threshold voltage U_ref is used to characterize the brightness threshold, and the brightness threshold U_ref is the switching condition between the start and stop of the lamp module.

[0111] The logic determination circuit 60 is specifically used to generate a switch logic signal S_ctr based on the digital level signal S_dg. When the level state of the digital level signal S_dg is an effective level state representing that the brightness sample value W_sp is lower than the brightness threshold W_ref, the level state of the switch logic signal S_ctr is an effective level state for starting the lamp module 80; and when the level state of the digital level signal S_dg is an ineffective level state representing that the brightness sample value W_sp is higher than or equal to the brightness threshold W_ref, the level state of the switch logic signal S_ctr is an ineffective level state for turning off the lamp module 80.

[0112] The LED driver circuit 70 is used to start the LED module 80 when the switch logic signal S_ctr is at an active level, and to turn off the LED module 80 when the switch logic signal S_ctr is at an inactive level. For example, the LED driver circuit 70 generates a constant current drive output I_drv that causes the LED module 80 to generate supplementary light brightness when the switch logic signal S_ctr is at an active level, and stops the constant current drive output I_drv to the LED module 80 when the switch logic signal S_ctr is at an inactive level.

[0113] The hysteresis control circuit 80 is used to adjust the adjustable resistance value R_adj based on the switching logic signal S_ctr (i.e., the state of the LED module 80), and the specific adjustment method is as described above.

[0114] Figure 6 For example Figure 5 The diagram shows an example of the signal processing circuit and logic decision circuit in the control device.

[0115] Please see Figure 6 The signal processing circuit 50 preferably includes a second switching element QS52. For example, the second switching element QS52 may include a transistor, and the transistor included in the second switching element QS52 may be an NPN transistor.

[0116] The cutoff voltage of the second switching element QS52 is related to the threshold voltage U_ref, or in other words, the cutoff voltage of the second switching element QS52 is used to characterize the threshold voltage U_ref, where:

[0117] When the voltage value of the sampled voltage signal U_sen is lower than the threshold voltage U_ref, the second switch element QS52 is closed, and the level state of the digital level signal S_dg is set to an effective level state indicating that the brightness sampled value W_sp is lower than the brightness threshold W_ref due to the closure of the second switch element QS52.

[0118] When the voltage value of the sampled voltage signal U_sen is higher than or equal to the threshold voltage U_ref, the second switching element QS52 is turned off, and the level state of the digital level signal S_dg is set to an invalid level state indicating that the brightness sampled value W_sp is higher than or equal to the brightness threshold W_ref due to the turning off of the second switching element QS52.

[0119] Specifically, the collector of the second switching element QS52 is at the same potential as the operating voltage Vcc5 (e.g., 5V) of the signal processing circuit 50 through the current-limiting resistor R55. The emitter of the second switching element QS52 is grounded. An energy storage capacitor C52 is also connected between the collector and emitter of the second switching element QS52. Furthermore, the base of the second switching element QS52 is controlled by the sampling voltage signal U_sen, thus:

[0120] When the voltage value of the sampled voltage signal U_sen is higher than or equal to the threshold voltage U_ref, the voltage Ube between the base and emitter of the second switching element QS52 is less than or equal to its cutoff voltage. At this time, the second switching element QS52 is turned off, and the operating voltage Vcc5 stores energy in the energy storage capacitor C52, so that a high level is generated at the collector of the second switching element QS52 that is at the same potential as the operating voltage Vcc5. That is, the invalid level state of the digital level signal S_dg generated at the collector of the second switching element QS52 can be a high level.

[0121] When the voltage value of the sampled voltage signal U_sen is lower than the threshold voltage U_ref, the voltage Ube between the base and emitter of the second switching element QS52 is greater than its cutoff voltage. At this time, the second switching element QS52 is turned on, and the energy storage capacitor C52 discharges, so that a low level equal to ground is generated at the collector of the second switching element QS52. That is, the effective level state of the digital level signal S_dg generated at the collector of the second switching element QS52 can be low.

[0122] See also Figure 6 In order to control the voltage Ube between the base and emitter of the second switching element QS52 based on the sampled voltage signal U_sen, the signal processing circuit 50 preferably includes a third switching element QS51. For example, the third switching element QS51 may include a transistor, and the transistor included in the third switching element QS51 may be a PNP transistor.

[0123] Specifically, the emitter of the third switching element QS51 is at the same potential as the operating voltage Vcc5 (e.g., 5V) of the signal processing circuit 50 through the pull-up resistor R51, the collector of the third switching element QS51 is grounded through the pull-down resistor R52, and the base of the third switching element QS51 is connected to the voltage output terminal of the signal sampling circuit 20. That is, the base of the third switching element QS51 is at the same potential as the sampled voltage signal U_sen, and the base of the second switching element QS52 is at the same potential as the collector of the third switching element QS51.

[0124] When the voltage value of the sampled voltage signal U_sen is higher than or equal to the threshold voltage U_ref:

[0125] The voltage Ube between the base and emitter of the third switching element QS51 is less than or equal to its cutoff voltage. At this time, the current flowing through the pull-down resistor R52 is small or even zero, and the potentials of the collector of the third switching element Q51 and the base of the second switching element QS52 are pulled low.

[0126] Therefore, the voltage Ube between the base and emitter of the second switching element QS52 is less than or equal to its cutoff voltage, the second switching element QS52 is turned off, and the operating voltage Vcc5 stores energy in the energy storage capacitor C52, thereby causing a high level at the collector of the second switching element QS52 to be at the same potential as the operating voltage Vcc5. That is, the invalid level state of the digital level signal S_dg generated at the collector of the second switching element QS52 can be a high level.

[0127] When the voltage value of the sampled voltage signal U_sen is lower than the threshold voltage U_ref:

[0128] The voltage Ube between the base and emitter of the third switching element QS51 is greater than its cutoff voltage. At this time, the current flowing through the pull-down resistor R52 is larger, and the potentials of the collector of the third switching element Q51 and the base of the second switching element QS52 are pulled high.

[0129] Therefore, the voltage Ube between the base and emitter of the second switching element QS52 is greater than its cutoff voltage, the second switching element QS52 is turned on, and the energy storage capacitor C52 discharges, thereby generating a low level at the collector of the second switching element QS52 that is at the same potential as ground. That is, the effective level state of the digital level signal S_dg generated at the collector of the second switching element QS52 can be low.

[0130] That is, the third switching element Q51 can be considered as being used to convert the sampled voltage signal U_sen into a linear current signal with which it has a linear relationship, and the voltage generated by the linear current signal in the pull-down resistor R52 is used to replace the sampled voltage signal U_sen to control the on and off states of the second switching element QS52.

[0131] In addition, a filter circuit can be connected between the base of the second switching element QS52 and the collector of the third switching element Q51. The filter circuit may include a filter resistor R53 connected in series between the base of the second switching element QS52 and the collector of the third switching element Q51, and a filter capacitor C51 connected between the base of the second switching element QS52 and ground.

[0132] Please continue reading Figure 6 When the effective level state of the digital level signal S_dg is low and the invalid level state of the digital level signal S_dg is high, the logic determination circuit 60 may include a gate array, such as an FPGA (Field Programmable Gate Array) or a CPLD (Complex Programmable Logic Device).

[0133] Specifically, the gate array of the logic decision circuit 60 may include an OR gate G61, a NAND gate G62, and an AND gate G63, wherein:

[0134] The two inputs of the OR gate G61 receive a digital level signal S_dg and a reference level signal that is continuously high, respectively. For example, the reference level signal can be the operating voltage Vcc6 of the logic determination circuit 60.

[0135] The two inputs of the NAND gate G62 receive the digital level signal S_dg and the aforementioned reference level signal, respectively.

[0136] The two input terminals of AND gate G63 are connected to the output signals of OR gate G61 and NAND gate G62, respectively, and the output signal of AND gate G63 is the switching logic signal S_ctr.

[0137] Referring to Table 1 below, when the digital level signal S_dg is at a valid low level "0", the switch logic signal S_ctr is at a valid high level "1", and when the digital level signal S_dg is at an invalid high level "1", the switch logic signal S_ctr is at an invalid low level "0".

[0138]

[0139] Table 1: Relationship between the level states of digital level signal S_dg and switching logic signal S_ctr

[0140] Assuming the brightness threshold is 2 lux and the threshold voltage is 2V, then, based on the digital level signal S_dg along... Figure 4 The level changes of the startup and shutdown process curves shown can be found in Table 2 below.

[0141]

[0142] Table 2: Relationship between the level states of digital level signal S_dg and switching logic signal S_ctr

[0143] In another embodiment of this application, a supplementary light is provided, which may include the control device and the LED module 80 described in the foregoing embodiments.

[0144] In this embodiment of the application, the fill light can be a separate light body independent of the camera, or it can be integrated into the camera.

[0145] Accordingly, in another embodiment of this application, a camera is also provided. This camera may include the supplementary light (including the control device and LED module 80 as described above) and an optical imaging component. The optical imaging component may include an image sensor for photosensitive imaging, such as a CCD (Charge Coupled Device) or CMOS, and may also include a lens whose field of view covers the photosensitive surface of the image sensor. Furthermore, the camera may also include an image processing module, which may include at least one processor with image processing capabilities.

[0146] In an embodiment of this application, a fill light control method is also provided, which may include:

[0147] Acquire a photocurrent signal, which includes a first photocurrent signal or a second photocurrent signal. That is, the photocurrent signal can be a first photocurrent signal obtained at a first moment during the period when the lamp module is off, or a second photocurrent signal obtained at a second moment during the period when the lamp module is on. The first photocurrent signal is obtained based on the first ambient brightness during the process of the ambient light brightness in the monitoring area changing from strong to weak when the lamp module of the supplementary light is off, and the second photocurrent signal is obtained based on the second ambient brightness during the process of the ambient light brightness in the monitoring area changing from weak to strong when the lamp component of the supplementary light is on. Furthermore, the brightness values ​​of the first ambient brightness and the second ambient brightness are the same.

[0148] The acquired photocurrent signal is input to a preset signal sampling circuit, which is configured to generate a sampling voltage signal based on the photocurrent signal and the equivalent sampling resistance.

[0149] Based on the comparison between the sampled voltage signal and the threshold voltage, the LED module is controlled to turn on and off, wherein:

[0150] The equivalent sampling resistance value is the first resistance value when the lamp module is off, so that the sampling voltage signal obtained based on the first photocurrent signal has a first voltage value for characterizing the first ambient brightness.

[0151] The equivalent sampling resistance value is the second resistance value when the lamp module is turned on, so that the sampling voltage signal obtained based on the second photocurrent signal has a second voltage value for characterizing the second ambient brightness.

[0152] The first resistance value is greater than the second resistance value, and the first voltage value is greater than the second voltage value, so that the LED module is turned on when the first voltage value is less than the threshold voltage and turned off when the second voltage value is greater than the threshold voltage.

[0153] Therefore, although the first voltage value and the second voltage value correspond to the same first ambient brightness and second ambient brightness, since the first ambient brightness and the second ambient brightness are the ambient brightness during the periods when the lamp module is off and on, respectively, the second ambient brightness includes the supplementary light brightness. Therefore, the second voltage value is less than the first voltage value, so as to represent the true ambient brightness after subtracting the supplementary light brightness from the second ambient brightness. Thus, by using the second point suppression as the shutdown condition of the lamp module, the false triggering of the lamp-off operation by the supplementary light brightness can be suppressed, and the repeated lamp-on operation following the false triggering lamp-off operation can be suppressed.

[0154] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A control device for a light supplement lamp, characterized in that include: A brightness sensing component is used to generate a photocurrent signal based on the sensed ambient brightness, and the current value of the photocurrent signal is associated with the ambient brightness; A signal sampling circuit is used to generate a sampling voltage signal based on the photocurrent signal. The voltage value of the sampling voltage signal is proportional to the current value of the photocurrent signal. The proportionality coefficient between the voltage value of the sampling voltage signal and the current value of the photocurrent signal is an adjustable resistance value. Furthermore, the voltage value of the sampling voltage signal is used as a brightness sampling value to characterize the ambient brightness. A signal processing circuit is used to generate a digital level signal based on the sampled voltage signal, and the level state of the digital level signal is used to characterize the comparison result between the voltage value of the sampled voltage signal and the threshold voltage. A logic determination circuit is used to generate a switching logic signal based on the digital level signal; wherein, the logic determination circuit includes a gate array, the threshold voltage is used to characterize a brightness threshold, the brightness threshold is a switching condition between the start and stop of the LED module of the supplementary light, the level state of the switching logic signal is set to an effective level state for indicating the start of the LED module when the comparison result characterized by the digital level signal is that the voltage value of the sampled voltage signal is lower than the threshold voltage, and the level state of the switching logic signal is set to an invalid level state for indicating the stop of the LED module when the comparison result characterized by the digital level signal is that the voltage value of the sampled voltage signal is higher than or equal to the threshold voltage; A hysteresis control circuit is used to adjust the adjustable resistor value based on the switching logic signal, wherein adjusting the adjustable resistor value includes: When the switch logic signal is at an active level, the adjustable resistor value is reduced from a first resistance value to a second resistance value to suppress the voltage value increment of the sampled voltage signal caused by the supplementary light brightness generated by the lamp module when the lamp module is started. When the switch logic signal is in an invalid level state, the adjustable resistor value is raised from the second resistance value to the first resistance value, so as to remove the suppression of the voltage value of the sampled voltage signal when the lamp module is turned off; The suppression of the voltage increment is used to make the brightness sample value represented by the sampled voltage signal have a preset brightness drop below the ambient brightness when the lamp module is started. The preset brightness drop is used to make the triggering time of the lamp module switching from the start state to the off state have a hysteresis relative to the current real brightness value of the ambient brightness rising to be equal to or higher than the brightness threshold.

2. The control device according to claim 1, characterized in that, The signal sampling circuit includes a sampling resistor, and the hysteresis control circuit includes a compensation resistor; The first resistance value is the resistance value of the sampling resistor, and the second resistance value is the equivalent resistance value when the sampling resistor and the compensation resistor are connected in parallel: The hysteresis control circuit is specifically used for: When the switch logic signal is at an active level, the parallel connection between the compensation resistor and the sampling resistor is enabled. When the switch logic signal is in an invalid level state, the parallel connection between the compensation resistor and the sampling resistor is removed.

3. The control device according to claim 2, characterized in that, The signal sampling circuit includes a current receiving terminal for receiving the photocurrent signal and a voltage output terminal for generating the sampling voltage signal. The sampling resistor is connected in series in the solidified current loop between the voltage output terminal and ground, and the solidified current loop is connected to the current receiving terminal. The compensation resistor is connected in series in the controllable current loop between the voltage output terminal and ground. The controllable current loop is connected to the current receiving terminal, and the controllable current loop is connected in parallel with the curing current loop. The hysteresis control circuit is specifically used for: When the switch logic signal is at an active level, the controllable current loop is turned on to enable the parallel connection of the compensation resistor and the sampling resistor; When the switch logic signal is in an invalid level state, the controllable current loop is disconnected to cancel the parallel connection between the compensation resistor and the sampling resistor.

4. The control device according to claim 3, characterized in that, The hysteresis control circuit further includes a first switching element, which is connected in series with the compensation resistor in the controllable current loop, and: When the switch logic signal is at an active level, the first switch element is set to a closed state that enables the controllable current loop to conduct. When the switch logic signal is in an invalid level state, the first switch element is set to an open state that disconnects the controllable current loop.

5. The control device according to claim 1, characterized in that, The preset brightness difference is proportional to the threshold voltage; The preset brightness difference is inversely proportional to the brightness threshold; The preset brightness difference is proportional to the difference between the reciprocal of the second resistance value and the reciprocal of the first resistance value.

6. The control device according to claim 1, characterized in that, The effective level state is low, the invalid level state is high, and the gate array includes OR gates, NAND gates, and AND gates, wherein: The two inputs of the OR gate receive the digital level signal and the reference level signal that is continuously high, respectively. The two input terminals of the NAND gate receive the digital level signal and the reference level signal, respectively. The two input terminals of the AND gate are respectively connected to the output signals of the OR gate and the NAND gate, and the output signal of the AND gate is the switching logic signal.

7. A control device for a light supplement lamp, characterized in that include: A brightness sensing component is used to generate a photocurrent signal based on the sensed ambient brightness, and the current value of the photocurrent signal is associated with the ambient brightness; A signal sampling circuit is used to generate a sampling voltage signal based on the photocurrent signal. The voltage value of the sampling voltage signal is proportional to the current value of the photocurrent signal. The voltage value of the sampling voltage signal is used to characterize the ambient brightness as a brightness sampling value. The comparison result between the voltage value of the sampling voltage signal and a threshold voltage characterizing the brightness threshold is used to determine the state of the LED module of the supplementary light. Furthermore, the proportionality coefficient between the voltage value of the sampling voltage signal and the current value of the photocurrent signal is an adjustable resistance value. A signal processing circuit is used to generate a digital level signal based on the sampled voltage signal, and the level state of the digital level signal is used to characterize the comparison result between the voltage value of the sampled voltage signal and the threshold voltage. A logic determination circuit is used to generate a switching logic signal based on the comparison result of the voltage value of the sampled voltage signal and a threshold voltage. The logic determination circuit includes a gate array. The threshold voltage is used to characterize a brightness threshold, which is a switching condition between the start and stop of the LED module of the supplementary light. The level state of the switching logic signal is set to an effective level state for starting the LED module when the comparison result represented by the digital level signal is that the voltage value of the sampled voltage signal is lower than the threshold voltage. Furthermore, the level state of the switching logic signal is set to an ineffective level state for stopping the LED module when the comparison result represented by the digital level signal is that the voltage value of the sampled voltage signal is higher than or equal to the threshold voltage. Hysteresis control circuit, used for: When the LED module is in the off state, the adjustable resistor value is adjusted to the first resistance value; When the LED module is in the start state, the adjustable resistor value is adjusted to the second resistance value; The first resistance value is greater than the second resistance value, so that when the ambient brightness is at the same brightness value within the brightness range equal to or higher than the brightness threshold, the sampling voltage signal will have a first voltage value and a second voltage value lower than the first voltage value when the state of the lamp module is the off state and the on state, respectively. The first voltage value represents the first brightness sample value, which is matched with the current true brightness value of the ambient brightness, so that the lamp module switches from the off state to the on state and is triggered in response to the current true brightness value of the ambient brightness dropping below the brightness threshold. The second voltage value represents a second brightness sample value that is lower than the first brightness sample value. The second brightness sample value has a brightness drop compared to the current true brightness value of the ambient brightness. The brightness drop is used to trigger the lamp module to switch from the start state to the off state for the light-off operation. It has a hysteresis at the time when the current true brightness value of the ambient brightness rises to be equal to or higher than the brightness threshold.

8. The control device according to claim 7, characterized in that, The signal sampling circuit includes a sampling resistor, and the hysteresis control circuit includes a compensation resistor; The first resistance value is the resistance value of the sampling resistor, and the second resistance value is the equivalent resistance value when the sampling resistor and the compensation resistor are connected in parallel: The hysteresis control circuit is specifically used for: When the LED module is in the start-up state, the parallel connection of the compensation resistor and the sampling resistor is enabled; When the LED module is in the off state, disconnect the parallel connection between the compensation resistor and the sampling resistor.

9. The control device according to claim 7, characterized in that, The effective level state is low, the invalid level state is high, and the gate array includes OR gates, NAND gates, and AND gates, wherein: The two inputs of the OR gate receive the digital level signal and the reference level signal that is continuously high, respectively. The two input terminals of the NAND gate receive the digital level signal and the reference level signal, respectively. The two input terminals of the AND gate are respectively connected to the output signals of the OR gate and the NAND gate, and the output signal of the AND gate is the switching logic signal.

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