KR20230065046A - Low-cost luminance measurment device - Google Patents

Abstract

According to an embodiment of the present invention, a device for measuring luminance, which can be implemented at low cost, includes a barrel formed in a long passage structure; an illuminance sensor disposed in one of the holes on both sides of the lens barrel to sense the amount of front light collected through the remaining second holes; the substrate supporting the illuminance sensor and the lens barrel to minimize light leaking into the gap between the first hole and the substrate; and a controller configured to determine brightness, that is, brightness of light reflected from a front object, based on the amount of light sensed by the illuminance sensor.

Description

Luminance measurement device that can be implemented at low cost {LOW-COST LUMINANCE MEASURMENT DEVICE}

The present invention relates to a device for measuring luminance that can be implemented at low cost.

As a criterion for indicating the degree of brightness, illuminance indicates the amount of light incident on a target surface, and lx (lux) is used as a unit.

On the other hand, luminance indicates the amount of light reflected from a target surface, and cd/m ² is used as a unit.

Considering these criteria, a brightness detection sensor suitable for the case should be used. For example, when it is necessary to collect the brightness of light reflected from an area to be measured, a luminance sensor must be provided so that the performance of the equipment to which the sensor is attached can be properly demonstrated.

Recently, lighting devices that output adaptive output according to the brightness of the surroundings are being developed, away from lighting that outputs a constant amount of light. That is, lighting devices equipped with both a sensor for collecting brightness and a light source are appearing.

In this case, the brightness sensed by the sensor and the brightness irradiated by the light source must be clearly distinguished. Accordingly, a luminance sensor is preferably used as a sensor that collects brightness reflected from the measurement area. In particular, in the case of a lighting device included in mobile equipment, light reflected from a forward object such as a road must be sensed so that the output of the light source can be accurately controlled accordingly.

However, since the luminance sensor is expensive, it is difficult to employ it in general equipment. For example, in the case of a lighting device mounted on mobile mobility common to the public, such as bicycles, kickboards, delivery robots, and drones, it is practically impossible to have a luminance sensor.

Conversely, providing an illuminance sensor to cope with such an economic problem makes it difficult to ensure proper performance of the lighting device. For example, since the brightness around the sensor is sensed, it is inaccurate and easily exposed to the influence of the light emitted by the light source.

Accordingly, there is a demand for a brightness measuring device capable of practical use in consideration of economic feasibility while sensing light reflected from a front object rather than around the sensor.

The present invention is to solve the above-mentioned problems of the prior art, and includes a long passage-shaped lens barrel and detects light reflected from an object in front by arranging an illuminance sensor in one hole inside the barrel, Disclosed is a luminance measuring device that can be implemented as

According to an embodiment of the present invention, a device for measuring luminance, which can be implemented at low cost, includes a barrel formed in a long passage structure; an illuminance sensor disposed in one of the holes on both sides of the lens barrel to sense the amount of light collected through the remaining second holes; the substrate supporting the illuminance sensor to minimize light leaking into the gap between the first hole and the substrate; and a controller configured to determine brightness, that is, brightness of light reflected from a front object, based on the amount of light sensed by the illuminance sensor.

According to an embodiment of the present invention, the luminance measuring device further includes at least one light source for radiating light so that forward brightness is maintained at a first target brightness set according to the luminance determined by the controller.

According to an embodiment of the present invention, the illuminance sensor is spaced apart from the light source by a predetermined distance so as not to be affected by heat emitted from the light source.

According to an embodiment of the present invention, the luminance measuring device further includes a support part extending from a lower end of the lens barrel so that the lens barrel is fixed in close contact with the substrate.

According to an embodiment of the present invention, the luminance measuring device further includes at least one condensing lens disposed in an inner region of the lens barrel to amplify light collected through the second hole.

According to one embodiment of the present invention, the numerical value of the amount of light received and measured by the illuminance sensor through the second hole does not correspond to lx (lux) units.

According to an embodiment of the present invention, the control unit determines the luminance determined for a predetermined time from the time the light is received by the illuminance sensor, and sets the first target brightness corresponding to the luminance obtained by applying a predetermined ratio to the luminance. .

According to an embodiment of the present invention, the controller determines the maximum value of luminance determined for a predetermined time from the time when the illuminance sensor receives light, and sets the first target brightness in response to the luminance obtained by applying a predetermined ratio to the maximum value. Set up.

According to an embodiment of the present invention, after setting the first target brightness, the control unit sets the second target brightness corresponding to the luminance obtained by applying a preset ratio to the changed maximum value from a point in time when the maximum value is changed to a preset difference or more. is set to control the light source so that the front is maintained at the second target brightness.

According to an embodiment of the present invention, the controller determines the maximum and minimum values of luminance determined for a predetermined time from the time the light is received by the illuminance sensor, and responds to the luminance included in a predetermined range between the maximum and minimum values. Set the first target brightness.

According to an embodiment of the present invention, after setting the first target brightness, the control unit is included in a preset range between the maximum value and the minimum value, from a time when at least one of the maximum value and the minimum value is changed to a preset difference or more. A second target brightness corresponding to the luminance is set, and the light source is controlled so that the front is maintained at the second target brightness.

According to an embodiment of the present invention, the luminance measuring device further includes an input unit providing a light source brightness control function, and the control unit generates a brightness control input by the input unit after setting the first target brightness, The setting of the first target brightness is released, and the light source is controlled so that the front brightness is maintained with the brightness received from the input unit.

According to an embodiment of the present invention, the control unit determines the luminance for a predetermined time from the time the light is received by the illuminance sensor, and when the determined luminance is less than the first target brightness, the front is at the first target brightness. The amount of light output from the light source is determined so as to reach the light source, and the light source is turned off when the determined luminance is higher than the first target brightness.

A luminance measuring device according to an embodiment of the present invention can detect light reflected from a front object using an illuminance sensor.

A luminance measuring device according to an embodiment of the present invention is not affected by light output from a light source when measuring luminance according to a structure that seals around the illuminance sensor except for the front side.

In the luminance measuring device according to an embodiment of the present invention, the illuminance sensor and the light source are spaced apart from each other to prevent the illuminance sensor from being damaged by heat generated by the light source.

A luminance measuring device according to an embodiment of the present invention can be designed with an algorithm capable of controlling the output of a light source regardless of the brightness unit. That is, although the illuminance sensor replaces the function of the luminance sensor, the effect of maintaining the front at the intended target brightness is achieved.

In this way, according to one embodiment of the present invention, the function of an expensive luminance sensor can be replaced by using an inexpensive illuminance sensor. Furthermore, since it can be applied to light source control rather than simply measuring luminance, it is possible to implement a lighting device that saves battery and secures user safety and visibility.

1 is a perspective view of a luminance measuring device according to an embodiment of the present invention.
2 is a cross-sectional view of a luminance measuring device according to an embodiment of the present invention.
3 is a part diagram for explaining a coupling structure of a luminance measuring device equipped with a lighting function according to an embodiment of the present invention.
4 is a perspective view of a luminance measuring device equipped with a lighting function according to an embodiment of the present invention.
5 is a flow chart of a lighting control method according to an embodiment of the present invention.
6 is an exemplary view of a graph for explaining a lighting control algorithm according to an embodiment of the present invention.
7 is an exemplary view of a graph for explaining a change in target brightness in a lighting control algorithm according to an embodiment of the present invention.
8 is a flowchart illustrating another embodiment of a lighting control method.

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily practice the present invention with reference to the accompanying drawings. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein. And in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.

Throughout the specification, when a part is said to be "connected" to another part, this includes not only the case where it is "directly connected" but also the case where it is "electrically connected" with another element interposed therebetween. . In addition, when a certain component is said to "include", this means that it may further include other components without excluding other components unless otherwise stated.

Hereinafter, with reference to FIGS. 1 and 2, an embodiment of a structure of a luminance measurement device will be described in detail.

1 is a perspective view of a luminance measuring device according to an embodiment of the present invention.

2 is a cross-sectional view of a luminance measuring device according to an embodiment of the present invention.

An apparatus for measuring luminance according to an embodiment of the present invention may include a barrel 100 , an illuminance sensor 200 and a substrate 300 .

According to one embodiment, the barrel 100 may have a passage structure in which holes 101 and 102 are formed at both ends and have a length connecting them. The holes 101 and 102 may have preset diameters, and each hole may have the same or different diameters. That is, the inside of the barrel 100 may be in a cylindrical or truncated cone shape. In addition, in order to enhance the function of the barrel, an additional auxiliary means may be provided in one area inside and outside of the barrel, and the auxiliary means is not limited in its configuration, such as an auxiliary hole or a guide member.

According to an embodiment, the illuminance sensor 200 may be disposed in any first hole 101 of both holes of the barrel 100 . According to one embodiment, the first hole 101 can be closed without an empty space due to the arrangement of the illuminance sensor 200, and at this time, the illuminance sensor 200 can be accommodated at one end inside the barrel 100. . For example, the diameter of the first hole 101 may be set such that the circumference of the first hole 101 and all or part of the outer circumferential surface of the illuminance sensor 200 come into contact with each other.

According to an embodiment, the illuminance sensor 200 may be disposed in the first hole 101 and detect front light collected through the remaining second hole 102 .

According to an embodiment, since the lens barrel 100 is formed in a long passage structure and only the second hole 102 is open, light reflected from a preset sensing area in front is received through the illuminance sensor 200. can do. That is, since the periphery of the illuminance sensor 200 except for the direction of the second hole 102 is sealed, the brightness of the front, which is the direction of the second hole 102, can be sensed without the interference of light around the illuminance sensor 200.

In addition, since the second hole 102 is extended by the long passage structure of the lens barrel 100, interference of noise light during brightness detection can be further minimized.

According to an embodiment, a preset detection area in front may be specified by the second hole 102, like a pin hole used in a camera or the like. In this regard, the diameter of the second hole 102 and the length of the barrel 100 may be determined according to the distance to the object to be sensed for brightness and the area of the object.

According to a further embodiment, the barrel 100 may have an adjustable length. That is, the user may adjust the length of the lens barrel 100 to set the distance and area of the object to be sensed for brightness. Here, a method for adjusting the length of the barrel 100 may be a manual or automatic method, and a specific method does not limit the present invention.

According to a further embodiment, the second hole 102 may be openable. In a luminance measuring device including a light source, which will be described later, when a certain amount of light is to be irradiated without detection by the illuminance sensor 200, a command to close the second hole 102 may be transmitted to the controller. Accordingly, it is possible to reduce the possibility of unnecessary power consumption and malfunction. Here, the method of opening and closing does not limit the present invention.

According to one embodiment, the illuminance sensor 200 may be mounted on one region of the board 300, and preferably may be mounted on the center of the board 300. Here, the substrate 300 may include a controller (not shown) that controls overall operations of the luminance measurement device.

According to an embodiment, the substrate 300 is configured with the first hole 101 to prevent light from penetrating into a gap between the first hole 101 of the lens barrel 100 and the substrate 300. ), and can support the illuminance sensor 200 and the lens barrel 100 by being completely in close contact with one surface. Alternatively, light penetrating into the illuminance sensor 200 may be completely blocked in such a way that the barrel 100 penetrates the substrate 300 with a length equal to or less than the width of the substrate 300 .

According to one embodiment, the substrate 300 may support only the illuminance sensor 200 . For example, when the standard of the illuminance sensor 200 is equal to or greater than a preset standard, the barrel 100 may be supported by the illuminance sensor 200 .

According to an embodiment, the control unit of the luminance measuring device may receive a sensing value of light detected by the illuminance sensor 200 . Thereafter, luminance, which is the brightness of light reflected from a forward object in the direction of the second hole 102, may be determined based on the received sensing value.

According to an embodiment, the numerical value of the amount of light received and measured by the illuminance sensor 200 through the second hole 102 may not correspond to lx (lux) units. Although it is possible to measure the brightness corresponding to the luminance due to mechanical features including the lens barrel 100, the measured brightness does not mean the absolute value of the amount of light reflected from the object in front. That is, since the actual brightness of the front side is not detected, the role of the brightness sensor cannot be substituted if the original lx unit of the illuminance sensor 200 is applied. Accordingly, the controller may change the sensed value of the illuminance sensor 200 in a preset unit, measure the brightness corresponding to the luminance, and store the measured value. Here, the preset unit may be a conventional unit representing luminance or a unique unit preset in the controller to represent a relative value of brightness.

Through the above-described embodiments, even if an expensive luminance sensor is not provided, it is possible to measure brightness reflected from the front using an inexpensive illuminance sensor, thereby reducing cost. Therefore, since mass production is possible, it is not burdensome even when used in popular fields such as bicycles and kickboards, so high utilization can be expected. Of course, bicycles and kickboards are only examples, and any field in which lighting is used including mobility equipment such as delivery robots and drones should be interpreted as being included in the scope of the present invention.

As a representative example in which the luminance measuring device of the present invention is utilized, a portable lighting device that can be attached to a means of transportation such as a bicycle may be mentioned. For example, it is possible to implement a lighting device that measures the brightness (luminance) reflected from an object in front (the road ahead) in real time and determines the amount of light output from a light source based on the measured brightness, thereby maintaining a constant front brightness while driving. there is. That is, by reducing the amount of light irradiated in a bright space and increasing the amount of light irradiated in a dark space while driving, it is possible to save a battery and secure a driver's view and safety.

Of course, in the case of using only the conventional illuminance sensor, since the brightness around the sensor is measured instead of the brightness in the front, it is impossible to implement a lighting device that is mounted on a moving means and can output adaptively as described above.

Hereinafter, with reference to FIGS. 3 and 4 , a luminance measuring device equipped with a lighting function according to an embodiment of the present invention will be described.

3 is a part diagram for explaining a coupling structure of a luminance measuring device equipped with a lighting function according to an embodiment of the present invention.

4 is a perspective view of a luminance measuring device equipped with a lighting function according to an embodiment of the present invention.

According to an embodiment of the present invention, the luminance measurement device may include a first substrate 300 on which the barrel 100, the illuminance sensor 200 is mounted, and a second substrate 310 on which the light source 400 is mounted. there is. Any one of the first substrate 300 and the second substrate 310 may include a control unit that generally processes the operation of the luminance measurement device.

According to an embodiment, the surface of the barrel 100 where the first hole 101 is formed is in close contact with the first substrate 300, and the surface where the second hole 102 of the barrel 100 is formed is in close contact with the second substrate ( 310) may pass through one area. In this way, one side of the barrel 100 may be coupled to the first substrate 300 and the other side to the second substrate 310 .

According to one embodiment, the second substrate 310 may have a barrel penetration part 312 having a size corresponding to the diameter of the barrel 100 formed in the center. The barrel 100 may be coupled to the second substrate 310 by penetrating the barrel penetrating portion 312 .

According to an embodiment, the luminance measuring device may further include at least one light source 400 . For example, at least one or more light source mounting parts 311 may be formed around the barrel-through part 312 in the second substrate 310 . The light source 400 may be mounted on the light source mounting unit 311 in a direction parallel to the direction through which the lens barrel 100 passes. That is, the light source 400 may be disposed to radiate light to an area equal to or within a predetermined difference from the front area detected by the illuminance sensor 200 .

According to an embodiment, the light source 400 may emit light so that the brightness of the front is maintained at a target brightness set according to the luminance of the front determined by the controller. That is, the output intensity of the light source 400 may be controlled by the controller so that the corresponding area has a target brightness according to the brightness of the front area detected by the illuminance sensor 200 .

Here, the light source 400 may be an LED, and the type of the light source 400 does not limit the present invention.

According to an embodiment, the luminance measuring device may further include a support 110 extending from a lower end of the barrel 100 in a direction perpendicular to the barrel 100 . The support part 110 supports the main body of the barrel 100 so that the barrel 100 is fixed to the first substrate 300 in a state of close contact.

According to an embodiment, the support part 110 may include at least one protrusion 111 formed on a surface in contact with the first substrate 300 . For example, one protrusion 111 may be formed on the left and right sides of the first hole 101, respectively. By fastening the protrusion 111 to the support insertion hole 301 formed on the first substrate 300, the barrel 100 including the support 110 can be fixed to the first substrate 300 in a state of complete contact. can

According to an embodiment, the sensor mounting unit 302 may be formed on the first substrate 300 at a position corresponding to the center of the barrel 100 . The illuminance sensor 200 is coupled to and mounted on the sensor mounting unit 302, and as described above, the first substrate 300 and the barrel 100 may be accommodated inside the barrel 100 as they come into close contact with each other.

According to an embodiment, the illuminance sensor 200 and the light source 400 may be disposed in the luminance measuring device while being spaced apart by a preset distance. Accordingly, the illuminance sensor 200 may not be affected by the heat emitted from the light source 400, so that the lifespan of the sensor and the device is extended.

According to an embodiment, the support 110 of the lens barrel 100 may be formed to have a preset thickness, and the thickness may be set equal to the separation distance between the illuminance sensor 200 and the light source 400. Referring to FIG. 4 , the first substrate 300 on which the illuminance sensor 200 is mounted is attached to one side of the support 110, and the second substrate 310 on which the light source 400 is mounted is attached to the opposite side. Therefore, by appropriately adjusting only the thickness of the support portion 110, a structure that prevents the illuminance sensor 200 from being damaged by the heat of the light source 400 can be easily implemented.

According to a further embodiment, the support part 110 may include cylindrical support fixing pins (not shown) protruding in the direction of the second hole 102 on both sides. In addition, second substrate fixing holes (not shown) may be formed on both side surfaces of the second substrate 310 at positions corresponding to support fixing pins. For example, the support fixing pin may have a screw thread formed therein, and may be fastened together with the second substrate fixing hole with a screw. In this case, the distance between the illuminance sensor 200 and the light source 400 may be further separated by the protruding length of the support fixing pin, and thus the possibility of the illuminance sensor 200 being damaged by heat may be further reduced.

According to an embodiment, at least one condensing lens (not shown) may be further included between the first hole 101 and the second hole 102 inside the lens barrel 100 . The condensing lens serves to amplify the amount of light in case the light collected through the second hole 102 is insufficient to measure the luminance.

According to a further embodiment, the luminance measuring device may further include a third substrate 320 on which a control unit is mounted. In this case, the first substrate 300 and the second substrate 310 may be designed to perform only processing related to the operation of the illuminance sensor 200 and the light source 400, respectively, according to a control command transmitted from the controller. Thus, the first substrate 300 and the second substrate 310 can be compactly implemented.

By dividing the substrate in this way, it is possible to reduce the size and weight of the lighting device. For example, as shown in FIG. 4 , the third substrate 320 may be vertically coupled to the first substrate 300 and the second substrate 310 . An empty space may be secured by the first substrate 300 and the third substrate 320, and a power supply unit (battery) may be disposed in the corresponding space. Accordingly, a compact design is possible because an arrangement space for a battery to be included in the portable lighting device is efficiently secured.

Meanwhile, as described above, the luminance measuring device may not measure brightness in lx units. In this case, if the controller directly controls the light source 400 to output a specific lx value corresponding to the measured luminance, light may be irradiated from the light source 400 differently from the actual intended brightness. Therefore, in order to accurately implement a method of adaptively outputting light according to front brightness, a specific algorithm may be further required in addition to mechanical characteristics.

Hereinafter, an algorithm for a lighting control method according to an embodiment of the present invention will be described with reference to FIGS. 5 to 7 . Here, a subject performing the lighting control method refers to a luminance measuring device according to an embodiment of the present invention.

5 is a flow chart of a lighting control method according to an embodiment of the present invention.

6 is an exemplary view of a graph for explaining a lighting control algorithm according to an embodiment of the present invention.

In step S510, after the lighting device is operated, a process of measuring front luminance for a predetermined time may be performed. For example, the controller may determine the maximum value of luminance determined for a preset time from the time when the illuminance sensor 200 receives light. Alternatively, as shown in FIG. 6 , the maximum and minimum values of luminance determined for a predetermined time from the time when the illuminance sensor 200 receives light may be grasped.

According to an embodiment, in the case of a luminance measuring device mounted on a moving means, the luminance measuring time may be determined based on the speed of the moving means. Alternatively, when the deviation of the luminance measured for a specific time falls within a preset range, the controller may consider that sufficient luminance has been collected and stop the luminance measurement time.

In step S520, the controller may set a first target brightness by applying a predetermined ratio to the maximum value identified in step S510. Here, the percentage means a percentage greater than 0%, equal to or less than 100%. For example, the first target brightness may be set corresponding to 50% of the maximum luminance, and the controller may control the output of the light source 400 so that the front is maintained at the first target brightness that is half of the maximum.

Alternatively, when the maximum value and the minimum value are identified in S510, the controller may set the first target brightness corresponding to the luminance included in the preset range therebetween. For example, as shown in FIG. 6 , the controller may set the average of the maximum and minimum values as the first target brightness, and control the output of the light source 400 so that the front is maintained at the first target brightness.

Meanwhile, target brightness may be required to be changed according to the location of the luminance measurement device. For example, in the case of a luminance measuring device mounted on a bicycle, it may enter a generally bright place such as a city or a generally dark place such as a tunnel while driving on a road where streetlights are repeatedly arranged. In this case, if the first target brightness is continuously applied, the forward brightness and field of view experienced by the driver may change rapidly, which is highly likely to cause a safety problem.

7 is an exemplary view of a graph for explaining a change in target brightness in a lighting control algorithm according to an embodiment of the present invention.

According to an embodiment, the controller may change the target brightness. In step S530, after setting the first target brightness, the controller determines that the maximum value is changed by more than a preset difference. Alternatively, it is determined that at least one of the maximum value and the minimum value is changed by more than a predetermined difference.

Referring to FIG. 7 , when the controller sets the first target brightness, the process of measuring the luminance of the front side may continue as long as the corresponding light source control signal remains unchanged. Therefore, the control unit can automatically immediately determine the point in time when the maximum value or the minimum value differs by more than the reference range.

In step S540, the control unit changes the setting from the first target brightness to the second target brightness from the time determined in step S530. Referring to FIG. 7 , when the maximum value is changed by more than a preset difference, the controller calculates the second target brightness by applying a preset ratio to the changed maximum value. Here, the percentage means a percentage greater than 0%, equal to or less than 100%. Alternatively, when at least one of the maximum and minimum values is changed by more than a preset difference, the controller calculates the second target brightness included in a preset range between the changed maximum and minimum values. For example, the average of the changed maximum and minimum values may be set as the second target brightness.

Thereafter, the controller may control the output of the light source 400 so that the front is maintained at the second target brightness, thereby providing the user with brightness optimized according to changes in the environment.

Hereinafter, another embodiment of a lighting control method disclosed in the present invention will be described with reference to FIG. 8 .

8 is a flowchart illustrating another embodiment of a lighting control method.

In step S810, after the lighting device is operated, a process of measuring front luminance for a predetermined time is first performed. According to one embodiment, the measurement of luminance is continuously performed during operating time of the lighting device.

In step S820, the controller compares the measured value of luminance with a preset target brightness. According to an embodiment, the target brightness may mean a maximum value of luminance preset in the controller.

In step S830, when it is determined that the measured value of luminance is less than or equal to the target brightness, the controller determines the amount of light output from the light source 400 so that the measured value (measured brightness) reaches the target brightness. According to an embodiment, the luminance value corresponding to the amount of light output from the light source 400 is preferably a difference value between the target brightness (maximum value) and the measured value. That is, the controller controls the output of the light source 400 so that the front is maintained at a preset target brightness.

Conversely, when the measured value of luminance exceeds the target brightness, the OFF state of the light source 400 is maintained.

In step S840, the controller determines that the measured value of luminance exceeds the target brightness after a predetermined period of time has elapsed. That is, when the target brightness is the preset maximum value of luminance, it is determined whether or not the brightness of the front side is brighter than the reference value.

In step S850, when the measured value exceeds the target brightness, the controller controls the light source to be turned off. Conversely, if the measured value is continuously equal to or less than the target brightness, the process of controlling the light source so that the front is maintained at the target brightness (S830) is continuously performed.

As an additional embodiment, the luminance measurement device may further include a target brightness change button (not shown). The change of the target brightness may be automatically performed as described above, but may also be performed at the user's request. That is, steps S530 and S540 may be performed only when the user presses the corresponding button after the first target brightness is set. For example, the user may determine that the first target brightness is the most optimized forward brightness regardless of location. Alternatively, the user may be less sensitive to environmental changes. In this case, since changing the target brightness may waste unnecessary power, it is possible to prevent this and prolong the life of the battery through the present additional embodiment.

Meanwhile, the luminance measuring device according to an exemplary embodiment may further include an input unit (not shown) providing a light source brightness manipulation function. For example, desired front brightness may be different for each user. Alternatively, desired brightness may be different for each specific place or viewpoint even for the same user. In this case, the user may manually adjust the output intensity of the light source 400 through the light source brightness control function. At this time, even after a specific target brightness including the first target brightness is set, if a brightness manipulation input is generated by the input unit, the controller cancels the setting for the target brightness, and the forward brightness is set to the brightness received from the input unit. The output of the light source 200 may be controlled so as to be maintained.

The above description of the present invention is for illustrative purposes, and those skilled in the art can understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, the embodiments described above should be understood as illustrative in all respects and not limiting. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined form.

The scope of the present invention is indicated by the following claims rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and equivalent concepts should be construed as being included in the scope of the present invention. do.

100: body tube
101: 1st hole
102: 2nd hole
200: illuminance sensor
300: substrate
400: light source

Claims (13)

In a luminance measuring device that can be implemented at low cost,
a body tube formed in a long passage structure;
an illuminance sensor disposed in one of the holes on both sides of the lens barrel to sense the amount of front light collected through the remaining second holes;
the substrate supporting the illuminance sensor to minimize light leaking into the gap between the first hole and the substrate; and
A control unit for determining brightness, which is the brightness of light reflected from an object in front, based on the amount of light sensed by the illuminance sensor;
Luminance measuring device. According to claim 1,
The luminance measuring device further includes at least one light source for radiating light so that the front brightness is maintained at the first target brightness set according to the luminance determined by the controller. According to claim 2,
The luminance measuring device of claim 1 , wherein the illuminance sensor is spaced apart from the light source by a predetermined distance so as not to be affected by heat emitted from the light source. According to claim 1,
The luminance measuring device further comprises a support formed at a lower end of the lens barrel to fix the lens barrel in close contact with the substrate. According to claim 1,
The luminance measuring device further includes at least one condensing lens disposed in an inner region of the lens barrel to amplify light collected through the second hole. According to claim 1,
The luminance measuring device, wherein the value of the amount of light received and measured by the illuminance sensor through the second hole does not correspond to lx (lux) units. According to claim 2,
Wherein the control unit determines the luminance determined for a predetermined time from the time the light is received by the illuminance sensor, and sets the first target brightness corresponding to the luminance obtained by applying a predetermined ratio to the luminance. According to claim 2,
Wherein the control unit determines the maximum value of luminance determined for a predetermined time from the time when the illuminance sensor receives light, and sets the first target brightness corresponding to the luminance obtained by applying a predetermined ratio to the maximum value. According to claim 8,
After setting the first target brightness, the control unit sets a second target brightness corresponding to the luminance obtained by applying a predetermined ratio to the changed maximum value from the time point when the maximum value is changed to a preset difference or more, so that the front is the second target brightness. A luminance measurement device for controlling the light source to maintain brightness. According to claim 2,
The control unit determines the maximum and minimum values of luminance determined for a predetermined time from the time when the illuminance sensor receives light, and sets the first target brightness corresponding to the luminance included in a predetermined range between the maximum and minimum values. Luminance measuring device. According to claim 10,
After setting the first target brightness, the control unit sets a second target brightness corresponding to luminance included in a preset range between the changed maximum and minimum values, from the time when at least one of the maximum and minimum values is changed to a preset difference or more. The luminance measuring device controls the light source so that the front is maintained at the second target brightness by setting a. According to claim 2,
Further comprising an input unit providing a light source brightness manipulation function, wherein the controller cancels the setting of the first target brightness when a brightness manipulation input is generated by the input unit after setting the first target brightness, and the input unit A luminance measurement device for controlling the light source so that the brightness of the front is maintained with the brightness received from the luminance. According to claim 2,
The control unit determines the luminance for a predetermined time from the time the light is received by the illuminance sensor, and when the determined luminance is less than the first target brightness, the amount of light output from the light source so that the front reaches the first target brightness. to determine,
If the luminance determined later is higher than the first target brightness, turning off the light source, the luminance measuring device.

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