CN115981074A - Image pickup apparatus - Google Patents

Abstract

The invention provides an imaging device. The size of the device is suppressed, and the incidence of detection light for detecting the position of the filter to an imaging element in an imaging operation is prevented. The imaging device includes: a filter section having a 1 st filter and a 2 nd filter; a moving unit that moves the filter unit; a detection unit that detects a position of the filter unit; a storage section for storing the filter section, the moving section, and the detection section; an image pickup element which receives the light having passed through the filter portion and converts the light into an image signal; and a filter control unit that controls the start and stop of emission of the detection light from the detection light source of the detection unit. The moving unit disposes one of the 1 st filter and the 2 nd filter between the imaging element and the opening. The filter control unit causes the detection light source to start emitting the detection light at a predetermined timing, and causes the detection light source to stop emitting the detection light when the movement of the filter unit is completed.

Description

Image pickup apparatus

Technical Field

The present invention relates to an imaging apparatus.

Background

In various places such as care facilities, hospitals, factories, and stores, surveillance cameras are installed from the viewpoint of theft prevention, disaster prevention, and the like. Depending on the environment in which the monitoring camera serving as the imaging device is installed, the surroundings of the monitoring camera may become darker at night than during the day, and thus monitoring may become difficult. Therefore, a monitoring camera is known which illuminates an auxiliary illumination device to illuminate a monitoring object with infrared light when the surroundings are dark, and cuts off infrared light to capture an image with visible light when the surroundings are bright.

Patent document 1 describes a monitoring camera in which an infrared cut filter and a glass member are alternatively arranged on an optical path of a lens barrel in accordance with measured illuminance.

Patent document 2 describes a filter device that switches between an ND filter and a visible light cut filter. In this filter device, filters are switched by rotating a disk-shaped turntable on which ND filters and visible light cut-off filters are arranged on the same circumference. Patent document 2 describes that a photointerrupter can be used as a device for detecting the rotational position of the turntable.

Patent document 1: japanese patent laid-open publication No. 2019-97046

Patent document 2: japanese patent laid-open publication No. 2012-198410

However, if the photo-interrupter is provided outside the unit provided with the filter, there is a problem that the device becomes large. Further, if a photo-interrupter is provided inside the unit provided with the filter, the detection light of the photo-interrupter enters the image pickup device, and there is a problem that the generated image is adversely affected.

Disclosure of Invention

One aspect of the present invention is an imaging apparatus including: an illumination light source that emits illumination light for illuminating an object; a filter section having a 1 st region not allowing the illumination light to pass therethrough and a 2 nd region allowing the illumination light to pass therethrough; a moving unit that moves the filter unit; a detection unit having a detection light source that emits detection light for detecting a position of the filter unit, and a light receiving unit that receives the detection light; a housing unit that houses the filter unit, the moving unit, and the detecting unit; an imaging unit that receives, of the light that has passed through the opening, light that has passed through the filter unit housed in the housing unit and converts the light into an image signal; and a control unit that controls start and stop of emission of the detection light from the detection light source. The moving unit moves the filter unit to dispose one of the 1 st region and the 2 nd region between the imaging unit and the opening. The control unit causes the detection light source to start emitting the detection light at a predetermined timing, and causes the detection light source to stop emitting the detection light when the detection unit detects that the movement of the filter unit is completed.

According to the present invention, since the start of emission of the detection light for detecting the position of the filter unit and the stop of emission of the detection light can be controlled, it is possible to suppress a decrease in the image quality of the generated image due to the imaging of the detection light by the imaging unit during the imaging process by the imaging device.

Drawings

Fig. 1A and 1B are perspective views showing the appearance of an image pickup apparatus according to an embodiment.

Fig. 2A is a top view of the inside of the imaging device, and fig. 2B is a cross-sectional view of the imaging device.

Fig. 3A, 3B, and 3C are perspective views showing the appearance of the switching portion.

Fig. 4 is a block diagram showing a control system of the image pickup apparatus.

Fig. 5A, 5B, and 5C are diagrams illustrating the operation of the switching unit when the shooting mode is switched between the normal shooting mode and the night vision mode.

Fig. 6 is a flowchart for explaining the operation of the imaging apparatus.

Fig. 7 is a flowchart for explaining the operation of the imaging apparatus.

Description of the reference symbols

10: a camera device; 13: an image pickup element; 14: a lens (imaging optical system); 15: an opening part; 17: an illuminometer; 18: a switching unit; 31: a control unit; 34: a filter control unit; 35: an image processing unit; 161. 162: an illumination light source; 180: a filter part; 181: a 1 st filter; 182: a 2 nd filter; 183: a holding section; 186: a light shielding portion; 190: a moving part; 191: a drive section; 200: a detection unit; 201: detecting a light source; 202: a light receiving section; 210: a cage.

Detailed Description

Hereinafter, an imaging apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings.

The use of the imaging device is not particularly limited, and the imaging device is suitably installed as a monitoring camera or a care camera in a hospital, a care facility, a factory, a store, or the like. In addition, the image pickup apparatus can be switched to a photographable state and a non-photographable state. More specifically, the image pickup apparatus can be switched to an off state in which light is not incident on the imaging optical system and an on state in which light is incident on the imaging optical system. Also, when the image pickup apparatus is switched to the non-photographing state (off state), the person being photographed can recognize that the image pickup apparatus is switched to the non-photographing state. In addition, the imaging device can switch between imaging in the normal imaging mode and imaging in the night vision mode according to the brightness of the surrounding external environment. In the normal shooting mode, when the external environment is bright, shooting is performed by light incident on the imaging optical system. In the night vision mode, illumination light is emitted when the external environment is dark, and imaging of an object irradiated with the illumination light is performed.

Fig. 1A and 1B are external views of the imaging device 10. Fig. 1A is an external view of the image pickup apparatus 10 in an open state, and fig. 1B is an external view of the image pickup apparatus 10 in a closed state. Fig. 2A is a plan view of the inside of the image pickup apparatus 10, and fig. 2B is a sectional view of the image pickup apparatus 10 taken along the line a-a of fig. 2A.

As shown in fig. 1A, 1B, 2A, and 2B, the imaging apparatus 10 includes a housing 12 having a substantially rectangular parallelepiped shape. The case 12 includes a front portion 12a, a rear portion 12b, and side portions 12c, 12d, 12e, and 12f connected to respective sides of the front portion 12 a. In the following description, the direction of front surface portion 12a of case 12 is referred to as the upper side, the direction of rear surface portion 12b is referred to as the lower side, the direction of side surface portion 12c is referred to as the front side, the direction of side surface portion 12d is referred to as the left side, and the direction of side surface portion 12f is referred to as the right side.

A card slot 24 into which a memory card 48 (see fig. 4) is inserted, an opening 15, illumination light sources 161 and 162, and an illuminance meter 17 are provided in the front face 12a of the housing 12. The side surface portion 12d is provided with a power supply port 26 connected to a power supply cable.

The illumination light sources 161 and 162 are, for example, LEDs, and emit light having a wavelength in the infrared region (infrared rays and infrared rays). When shooting in a night vision mode, which will be described later, the imaging device 10 emits infrared light from the illumination light sources 161 and 162 as illumination light for illuminating an object.

The illuminance meter 17 is, for example, a light register or a photodiode, and receives light of the environment (external environment) around the imaging apparatus 10 and outputs a signal (luminance signal). That is, the illuminance meter 17 functions as an illuminance unit that detects brightness outside the imaging device 10.

As shown in fig. 2A and 2B, a lens cover 11, an image pickup device 13 as an image sensor such as a CMOS or CCD, a lens (imaging optical system) 14 for converging light from an object (object light) on an image pickup surface of the image pickup device 13, a switching unit 18, and a control unit 31 are housed in a housing 12 of the image pickup apparatus 10. As shown in fig. 2B, the lens cover 11, the image pickup device 13, the lens 14, and the switching unit 18 are arranged in parallel with the front face portion 12 a.

An opening 15 provided in the front portion 12a of the housing 12 is formed on the optical axis of the lens 14. The subject light having passed through the opening 15 enters the image pickup device 13 through the lens (imaging optical system) 14. The imaging element 13 is an imaging section as follows; the light that has passed through the filter 180 provided in the holder 210 of the switching unit 18, which will be described in detail later, among the light incident through the opening 15 provided in the housing 12 is received and photoelectrically converted to output an image signal. The image signal output from the image pickup device 13 is subjected to various processes by an image processing unit 35 (see fig. 4) described later, and image data is generated.

The lens cover 11 for opening and closing the opening 15 is disposed between the lens 14 and the opening 15 along the optical axis of the lens 14. The lens cover 11 is movably provided in any of an open position to open the opening portion 15 and a closed position to close the opening portion 15. The lens cover 11 moves on a surface perpendicular to the optical axis of the lens 14 (i.e., a surface parallel to the front surface portion 12 a). When the lens cover 11 is moved to the open position, the lens cover 11 is separated from the optical axis of the lens 14, and as shown in fig. 1A, an opening portion 15 formed on the optical axis of the lens 14 is opened (open state). This allows the lens 14 to be exposed from the opening 15 of the housing 12, and thus subject light can enter the image sensor 13 through the lens 14.

When the lens hood 11 is moved to the closed position, as shown in fig. 1B, the opening portion 15 of the housing 12 is closed by the lens hood 11 (closed state). This enables the lens 14 to be covered with the lens cover 11, and the lens 14 in the housing 12 to be protected. When the lens cover 11 is in the closed position shown in fig. 1B, it functions as a light shielding portion that restricts the incidence of the object light on the image pickup device 13. In addition, the lens hood 11 is also referred to as a lens barrier, a shutter, or the like.

The switching unit 18 switches between a state in which the illumination light from the illumination light sources 161 and 162 is not allowed to enter the image pickup device 13 and a state in which the illumination light is allowed to enter the image pickup device 13, according to the brightness (luminance) of the external environment around the image pickup device 10. The switching unit 18 will be described in detail later.

The substrate 31a is a base member that holds the imaging element 13, the control unit 31, and the switching unit 18. The substrate 31a is provided on the rear surface portion 12b side in the case 12.

The control unit 31 is constituted by a CPU, a memory, and the like. The control unit 31 is a processor that controls each unit of the imaging apparatus 10 by reading and executing a control program recorded in advance in a recording medium 38 (see fig. 4) such as a flash memory, for example. The control unit 31 performs a determination process of determining whether the external environment around the imaging device 10 is bright or dark based on the luminance signal output from the illuminometer 17. As a result of the determination processing, when the external environment is bright, the imaging mode of the imaging device 10 is set to the normal imaging mode, and when the external environment is dark, the imaging mode is set to the night vision mode. The details of the processing performed by the control unit 31 will be described later.

< regarding the switching part 18 >

Fig. 3A, 3B, and 3C are perspective views of the switching unit 18. Fig. 3A is a perspective view of the switching unit 18 from the front face 12a side, fig. 3B is a perspective view of the switching unit 18 from the rear face 12B side, and fig. 3C is a perspective view of the switching unit 18 from the rear face 12B side with a holder described later removed.

The switching unit 18 includes a filter unit 180, a moving unit 190, and a detection unit 200, which are housed in a holder 210 as a housing unit. The holder 210 is disposed on the substrate 31a so as to be positioned above the image pickup device 13. As shown in fig. 3A, the lens 14 is provided on the upper portion (front portion 12a side) of the holder 210.

The filter unit 180 includes a 1 st filter 181, a 2 nd filter 182, and a holder 183. The 1 st filter 181 is an infrared cut filter, and functions to prevent infrared light from passing through and entering the 1 st region of the image pickup device 13. The 2 nd filter 182 is a virtual lens or the like, and functions as a 2 nd area that allows infrared light to pass through and enter the image pickup device 13.

The holding unit 183 is a holding frame that holds the 1 st filter 181 and the 2 nd filter 182 in a plane parallel to the front face portion 12 a. As shown in fig. 2B, the holding unit 183 is disposed between the image pickup device 13 and the lens 14 in parallel with the image pickup plane of the image pickup device 13. The holding portion 183 is formed of, for example, a metal material. Therefore, the holding unit 183 can obtain sufficient strength for holding the 1 st filter 181 and the 2 nd filter 182 without increasing the thickness of the lens 14 in the optical axis direction.

The holding unit 183 holds the 1 st filter 181 on the side surface portion 12f side (right side) and the 2 nd filter 182 on the side surface portion 12d side (left side) along the direction in which guide rails 195 and 196 of the moving unit 190 (described later) extend (the direction of arrow AR in fig. 2A). When the holding unit 183 moves along the arrow AR in fig. 2A, one of the 1 st filter 181 and the 2 nd filter 182 is disposed on the optical axis of the lens 14 (i.e., between the image pickup device 13 and the opening 15). In the following description, the position of the holding unit 183 when the 1 st filter 181 is disposed on the optical axis of the lens 14 is referred to as the 1 st position, and the position of the holding unit 183 when the 2 nd filter 182 is disposed on the optical axis of the lens 14 is referred to as the 2 nd position. Fig. 2A, 3B, and 3C show the holding unit 183 at the 2 nd position.

The holding portion 183 is provided with coupling portions 184 and 185 and a light shielding portion 186. The coupling portion 184 is provided on the side surface portion 12c side of the holding portion 183. The coupling portion 184 is coupled to the guide rail 195 so that a part thereof is movable relative to the guide rail 195, and is engaged with a screw 194 of the moving portion 190, which will be described later, by a screw formed at another part thereof. The connection portion 185 is provided on the side surface portion 12e side of the holding portion 183. The coupling portion 185 is coupled to the rail 196 so as to be movable relative to the rail 196. The coupling portions 184 and 185 are coupled to the guide rails 195 and 196, respectively, and the holding portion 183 is coupled to the moving portion 190 so as to be movable in the direction of the arrow AR in fig. 2A.

The light shielding portion 186 is a plate-like member provided at an end portion of the coupling portion 185 on the side surface portion 12e side and having a light shielding surface parallel to the imaging surface of the imaging element 13. The light blocking portion 186 moves along the direction in which the guide rail 196 extends together with the holding portion 183 moved by the moving portion 190 described later. The light blocking portion 186 blocks detection light emitted from the detection portion 200 described later when the holding portion 183 moves.

The moving unit 190 includes a driving unit 191, a 1 st gear 192, a 2 nd gear 193, a lead screw 194, and guide rails 195 and 196. The driving unit 191 is, for example, a stepping motor, and is controlled by a control unit 31 described later. The rotation angle, the rotation speed, and the like of the driving unit 191 are controlled by inputting a driving signal (pulse signal) from the control unit 31 described later to the driver of the driving unit 191. The rotation angle of the driving part 191 is proportional to the number of pulses, and the rotation speed of the driving part 191 is proportional to the pulse frequency.

The guide rails 195, 196 are arranged parallel to each other in the direction of the arrow AR of fig. 2A. The 1 st gear 192 is coupled to a rotation shaft that is a rotation center of the driving unit 191, and rotates according to the rotation of the driving unit 191. The 2 nd gear 193 is engaged with the 1 st gear 192, and when the 1 st gear 192 is rotated by the driving unit 191, it is rotated in accordance with the rotation of the 1 st gear 192.

The screw 194 is connected to a rotation shaft that is the rotation center of the 2 nd gear 193, and extends in the direction of the arrow AR in fig. 2A in parallel with the guide rail 195. When the 2 nd gear 193 rotates according to the rotation of the 1 st gear 192, the lead screw 194 rotates according to the rotation of the 2 nd gear 193. A screw 194 is formed with a thread, and is engaged with a thread formed in a part of the coupling portion 184. When the screw 194 rotates, the coupling portion 184 coupled via the screw moves relative to the screw 194. At this time, the coupling portion 184 is guided by the coupled guide rail 195, and moves in the direction of the arrow AR in fig. 2A. As the coupling portion 184 moves, the holding portion 183 and the coupling portion 185 coupled to the guide rail 196 move in the direction of the arrow AR in fig. 2A.

The moving direction of the coupling portion 184, that is, the moving direction of the holding portion 183 is changed by switching the rotating direction of the driving portion 191. For example, when the driving unit 191 is rotated forward, the lead screw 194 rotates clockwise, and the holding unit 183 moves from the 1 st position to the 2 nd position. When the driving unit 191 is rotated reversely, the screw shaft 194 rotates counterclockwise, and the holding unit 183 moves from the 2 nd position to the 1 st position. That is, by switching the rotation direction of the driving unit 191, one of the 1 st filter 181 and the 2 nd filter 182 can be arranged on the optical axis of the lens 14.

The detection unit 200 is a photo-interrupter including a detection light source 201 and a light receiving unit 202 provided at a position facing the detection light source 201. The detection light source 201 is, for example, an LED, and emits light having a wavelength in the infrared region (infrared light ) as detection light toward the light receiving unit 202. The light receiving unit 202 is, for example, a phototransistor, and generates an electric signal having a value (current value) corresponding to the amount of received light when receiving the detection light emitted from the detection light source 201, and outputs the electric signal as a detection signal to the control unit 31.

When the light shielding portion 186 provided in the holding portion 183 does not pass between the detection light source 201 and the light receiving portion 202, the detection light is not shielded by the light shielding portion 186. Therefore, the light receiving unit 202 receives the detection light from the detection light source 201 and outputs a large current value as a detection signal. On the other hand, while the light shielding portion 186 provided in the holding portion 183 passes between the detection light source 201 and the light receiving portion 202, the detection light is shielded by the light shielding portion 186 and is not received by the light receiving portion 202. Therefore, the light receiving section 202 outputs a small current value as a detection signal. Thus, the control unit 31 can detect the position of the holding unit 183 based on the magnitude of the current value obtained as the detection signal.

< control system for image pickup apparatus 10 >

Fig. 4 is a block diagram showing a control system of the image pickup apparatus 10. As shown in fig. 4, the control unit 31 of the imaging apparatus 10 includes an imaging control unit 33, a filter control unit 34, and a recording medium 38.

The imaging control unit 33 performs imaging processing as follows: the driving of the image pickup device 13 is controlled to generate an image signal, and the image processing unit 35 generates image data based on the image signal. In addition, when shooting is performed in the night vision mode, the imaging control unit 33 supplies power to the illumination light sources 161 and 162, and emits infrared light as illumination light.

The filter control unit 34 controls the start and end of emission of the detection light from the detection light source 201 of the detection unit 200. The filter control unit 34 controls the start and end of the movement operation for moving the filter unit 180. As the movement operation, the filter control unit 34 controls the movement of the holding unit 183 by driving the driving unit 191 in accordance with the set shooting mode, and thereby, either one of the 1 st filter 181 and the 2 nd filter 182 is arranged on the optical axis of the lens 14. In this case, the filter control unit 34 arranges the 1 st filter 181 as the infrared cut filter on the optical axis of the lens 14 when shooting is performed in the normal shooting mode, and arranges the 2 nd filter 182 as the virtual lens on the optical axis of the lens 14 when shooting is performed in the night vision mode. That is, the filter control unit 34 positions the holding unit 183 at the 1 st position when imaging is performed in the normal imaging mode, and positions the holding unit 183 at the 2 nd position when imaging is performed in the night vision mode.

An actuator 44 is connected to the lens cover 11 that opens and closes the opening 15 via a link mechanism 43. A drive circuit 45 is connected to the actuator 44. The drive circuit 45 is connected to the control unit 31, and drives the actuator 44 in accordance with a control signal (drive signal) from the control unit 31.

< processing with respect to the control unit 31 >

The image pickup apparatus 10 starts shooting when the shooting execution condition is satisfied. The shooting execution conditions include the proximity of a wireless tag such as an IC tag to a predetermined range, the reception of a video signal transmitted from a portable terminal such as a smartphone, the reception of infrared rays transmitted from a remote controller, and the detection of sound of predetermined contents by a microphone not shown.

When the shooting execution condition is satisfied, the image pickup apparatus 10 moves the lens hood 11 from the closed position to the open position, and performs shooting of the object. That is, the control unit 31 causes the drive circuit 45 to drive the actuator 44, and moves the lens cover 11 to the open position via the link mechanism 43. In addition, when the shooting execution condition is not established, the control unit 31 causes the drive circuit 45 to drive the actuator 44 to move the lens hood 11 to the closed position via the link mechanism 43.

When the lens cover 11 is moved to the open position, the image pickup device 13 receives the subject light incident through the opening 15 and outputs an image signal to the image processing unit 35. The image processing unit 35 is an image processing processor (ISP). The image processing unit 35 performs known image processing including, for example, AD conversion processing, signal amplification processing, white balance processing, and the like on the image signal output from the image pickup device 13, and generates image data.

Further, the control unit 31 performs determination processing. In this case, the control unit 31 calculates a value of luminance from the luminance signal output from the illuminometer 17, and determines that the external environment is bright when the value is equal to or greater than a predetermined threshold value, and determines that the external environment is dark when the value is less than the threshold value. The predetermined threshold value is set based on the result of the test or simulation, and is recorded in the recording medium 38 in advance.

< usual photographing mode >

When the brightness value detected by the illuminance meter 17 is equal to or greater than the threshold value and it is determined that the surrounding external environment is bright, the imaging device 10 sets the imaging mode to the normal imaging mode and performs imaging. In the normal shooting mode, the filter control unit 34 controls the movement unit 190 so that the 1 st filter 181 is positioned on the optical axis of the lens 14. That is, in a state where infrared light is not incident, the image pickup element 13 performs photoelectric conversion and outputs an image signal. The image processing unit 35 generates image data using the image signal.

< about night vision mode >

When the value of the luminance detected by the illuminance meter 17 is smaller than the threshold value and it is determined that the surrounding external environment is dark, the imaging mode of the imaging device 10 is set to the night vision mode, and imaging is performed. In the night vision mode, when the external environment is dark and the light amount is insufficient, the imaging device 10 irradiates infrared light as illumination light and performs imaging of an object illuminated by the infrared light. The filter controller 34 controls the moving unit 190 to retract the 1 st filter 181 from the optical axis of the lens 14 and to dispose the 2 nd filter 182 on the optical axis of the lens 14. This allows infrared light to enter the imaging device 13. Then, as described above, the imaging control unit 33 causes the infrared light from the illumination light sources 161 and 162 to be emitted as illumination light.

Since the 2 nd filter 182 is positioned on the optical axis of the lens 14, the image pickup device 13 receives reflected light of the illumination light emitted from the illumination light sources 161 and 162 and reflected by the object, and outputs an image signal. The image processing unit 35 generates image data using the image signal.

< switching between normal photographing mode and night vision mode >

The operation of the switching unit 18 when switching between the normal imaging mode and the night vision mode will be described with reference to fig. 5A to 5C. Fig. 5A to 5C are perspective views from the rear surface portion 12b side in a state where the holder 210 is removed, as in fig. 3C, and fig. 5A shows a case where the holding portion 183 is located at the 2 nd position in the night vision mode. Fig. 5B shows a case where the holding portion 183 is located in the middle between the 1 st position and the 2 nd position. Fig. 5C shows a case where the holding part 183 is located at the 1 st position in the normal shooting mode.

The imaging mode is switched at a predetermined timing when the luminance of the external environment detected by the illuminance meter 17 changes from less than the threshold value to not less than the threshold value (when the luminance of the external environment changes to brighter) or when the luminance of the external environment changes from not less than the threshold value to less than the threshold value (when the luminance of the external environment changes to darker). At the predetermined timing, the filter control unit 34 controls the switching unit 18 to switch the 1 st filter 181 and the 2 nd filter 182, and emits the detection light from the detection light source 201 of the detection unit 200.

When the control unit 31 determines that the imaging mode is switched between the normal imaging mode and the night vision mode, the filter control unit 34 energizes the detection unit 200 to turn on the detection light source 201 to emit detection light, and energizes the driving unit 191 included in the moving unit 190 of the switching unit 18 to output a driving signal to move the holding unit 183. That is, the filter control unit 34 controls the emission of the detection light from the detection light source 201 to be synchronized with the start of the movement operation of the movement unit 190.

As shown in fig. 5A, when holding unit 183 is at position 2, detection unit 200 is located on the left side (side surface 12d side) of the left end of light shielding unit 186. Therefore, the light shielding portion 186 does not shield the detection light from the detection light source 201, and the detection light is received by the light receiving portion 202. Therefore, the current value as the detection signal from the light receiving section 202 becomes the 1 st value. In order to switch the imaging mode from the night vision mode to the normal imaging mode from this state, the filter control unit 34 drives the driving unit 191 counterclockwise at a predetermined rotational speed, for example.

When the holding unit 183 starts moving by the driving unit 191, as shown in fig. 5B, the light shielding unit 186 passes between the detection light source 201 and the light receiving unit 202 of the detection unit 200, and blocks the incidence of the detection light to the light receiving unit 202. Therefore, during the movement of the holding unit 183, the current value as the detection signal from the light receiving unit 202 becomes the 2 nd value smaller than the 1 st value when the holding unit 183 is at the 2 nd position.

When the light shielding portion 186 moves to the 1 st position as shown in fig. 5C as a result of the driving portion 191 being driven at the predetermined rotation speed, the detection portion 200 is located on the right side (side surface portion 12f side) of the right end portion of the light shielding portion 186. Therefore, the light shielding portion 186 does not shield the detection light from the detection light source 201, and the detection light is received by the light receiving portion 202. Therefore, the current value as the detection signal from the light receiving section 202 becomes the 1 st value.

On the other hand, when the shooting mode is switched from the normal shooting mode to the night vision mode, the filter control unit 34 drives the driving unit 191 clockwise at a predetermined rotational speed, for example. In this case, the holding portion 183 moves from the 1 st position shown in fig. 5C to the 2 nd position shown in fig. 5A via the state shown in fig. 5B. In this case, the detection signal from the light receiving unit 202 also changes from the 1 st value to the 2 nd value and then again changes to the 1 st value, similarly to the case of switching from the night vision mode to the normal imaging mode.

When detecting that the current value of the detection signal has changed to the 1 st value again after changing to the 2 nd value, the filter control unit 34 determines that the movement of the holding unit 183 is completed. When the movement of the holding unit 183 is completed, the energization of the detection unit 200 is terminated, and the detection light source 201 is turned off to terminate the emission of the detection light. Then, the filter control unit 34 terminates the energization of the driving unit 191, stops the output of the driving signal, and terminates the movement of the filter unit 180 by the moving unit 190. That is, the filter control unit 34 synchronizes the end of the emission of the detection light from the detection light source 201 with the end of the movement operation of the movement unit 190.

The processing performed by the control unit 31 when switching the shooting mode between the normal shooting mode and the night vision mode will be described with reference to flowcharts shown in fig. 6 and 7. Each process shown in the flowchart is performed by the control unit 31 reading out a program recorded in the recording medium 38 and executing the program. In addition, the flowcharts shown in fig. 6 and 7 show the respective processes executed when switching from the night vision mode to the normal shooting mode is performed.

The flowcharts shown in fig. 6 and 7 are started when the control unit 31 determines that the luminance of the external environment detected by the illuminometer 17 has changed from less than the threshold value to the threshold value or more.

In step S1 of fig. 6, the filter control unit 34 starts the energization of the detection unit 200 to emit detection light from the detection light source 201, and starts the movement operation by performing the energization to the drive unit 191. Then, the process advances to step S2. In step S2, the control unit 31 reads a detection signal from the light receiving unit 202 of the detection unit 200. Then, the process advances to step S3.

In step S3, the filter control unit 34 determines whether or not the detection unit 200 is not shielded by the light shielding portion 186, based on the detection signal read in step S2. When the current value as the detection signal is the 1 st value, the filter control unit 34 determines that the detection unit 200 is not shielded by the light shielding portion 186 (affirmative determination), and the process proceeds to step S4. When the current value as the detection signal is the 2 nd value, the filter control unit 34 determines that the detection unit 200 is shielded by the light shielding unit 186 (negative determination), and the process proceeds to step S8 described later.

In step S4, the filter control unit 34 drives the drive unit 191 counterclockwise by 1 step. Then, the process advances to step S5. In step S5, the filter control unit 34 determines whether or not the detection unit 200 is blocked by the light blocking unit 186, based on the detection signal from the light receiving unit 202. When the current value as the detection signal is the 2 nd value, the filter control unit 34 determines that the detection unit 200 is shielded by the light shielding portion 186 (affirmative determination), and the process proceeds to step S12 described later. When the current value as the detection signal is the 1 st value, the filter control unit 34 determines that the detection unit 200 is not shielded by the light shielding portion 186 (negative determination), and the process proceeds to step S6.

In step S6, the filter control unit 34 determines whether or not the value of the counter that counts the number of rotations of the drive unit 191 is 300. If the counter value is 300, the filter control unit 34 makes an affirmative determination, and the process proceeds to step S7. In step S7, the filter control unit 34 terminates the energization of the detection unit 200 to terminate the emission of the detection light from the detection light source 201, and terminates the energization of the driving unit 191 to terminate the movement operation. Then, the control unit 31 ends all the processing as an error.

By performing the processing of steps S4 to S6, it can be determined whether or not the 1 st filter 181 and the 2 nd filter 182 move appropriately in accordance with the movement of the filter by the driver 191. If the driving unit 191 is driven before the counter reaches 300, the state in which the detection unit 200 is blocked is not obtained, it is considered that the 1 st filter 181 and the 2 nd filter 182 do not operate properly. Therefore, when the process of step S7 is executed with a negative determination made in step S6, the control unit 31 ends all the processes as an error.

If the value of the counter is not 300 in step S6, a negative determination is made by the filter control unit 34, and the process returns to step S4. At this time, the filter control unit 34 adds 1 to the value of the counter. By repeating the above-described processing of steps S4 to S6, it is possible to confirm whether the holding unit 183 is correctly positioned at the 2 nd position and move the holding unit 183 from the 2 nd position.

In step S8, which is a negative determination in step S3 and proceeds to, the filter control unit 34 drives the driving unit 191 clockwise by 1 step. Then, the process advances to step S9. In step S9, the filter control unit 34 determines whether or not the detection unit 200 is not shielded by the light shielding unit 186, based on the detection signal. When the current value as the detection signal is the 1 st value, the filter control unit 34 determines that the detection unit 200 is not shielded by the light shielding portion 186 (affirmative determination), and the process proceeds to step S12 described later. When the current value as the detection signal is the 2 nd value, the filter control unit 34 determines that the detection unit 200 is blocked by the light blocking unit 186 (negative determination), and the process proceeds to step S10.

In step S10, the filter control unit 34 determines whether or not the value of a counter that counts the number of rotations of the drive unit 191 is 100. When the counter value is 100, the filter control unit 34 makes an affirmative determination, and the process proceeds to step S11. In step S11, the filter control unit 34 ends the energization to the detection unit 200 to end the emission of the detection light from the detection light source 201, and ends the energization to the driving unit 191 to end the movement operation. Then, the control unit 31 ends all the processing as an error.

If the value of the counter is not 100 in step S10, a negative determination is made by the filter control unit 34, and the process returns to step S8. At this time, the filter control unit 34 adds 1 to the value of the counter. By repeating the above steps S8 to S10, the holding unit 183 displaced from the position can be positioned at the 2 nd position.

In step S12, the filter control unit 34 resets the counter value of the drive unit 191. After that, the process advances to step S13 of fig. 7. In step S13 of fig. 7, the filter controller 34 rotates the driver 191 counterclockwise by 1 step. Then, the process advances to step S14. In step S14, the filter control unit 34 determines whether or not the counter value is 124. If the value of the counter is not 124, the filter control unit 34 makes a negative determination, and the process returns to step S13. At this time, the filter control unit 34 adds 1 to the value of the counter. If the value of the counter is 124 in step S14, the filter control unit 34 makes an affirmative determination, and the process proceeds to step S15.

In step S15, the filter control unit 34 determines whether or not the detection unit 200 is not shielded by the light shielding unit 186, based on the detection signal. When the current value as the detection signal is the 1 st value, the filter control unit 34 determines that the detection unit 200 is not shielded by the light shielding portion 186 (affirmative determination), and the process proceeds to step S16. In step S16, the filter control unit 34 terminates the energization of the detection unit 200 to terminate the emission of the detection light from the detection light source 201, terminates the energization of the drive unit 191 to terminate the movement operation, and terminates all the processes.

When the current value as the detection signal is the 2 nd value in step S15, the filter control unit 34 determines that the detection unit 200 is shielded by the light shielding portion 186 (negative determination), and the process proceeds to step S17. In step S17, the filter control unit 34 rotates the drive unit 191 further counterclockwise by 1 step, and the process returns to step S15.

The above-described flowchart shows the processing when switching from the night vision mode to the normal imaging mode is performed. When switching from the normal shooting mode to the night vision mode is performed, the processing shown in fig. 6 and 7 may be started when it is determined that the luminance of the external environment has changed from above the threshold value to dark to below the threshold value, and the driver 191 may be rotated clockwise in steps S4, S13, and S17, and the driver 191 may be rotated counterclockwise in step S8.

According to the above embodiment, the following operational effects can be obtained.

(1) The switching unit 18 of the imaging apparatus 10 includes a filter unit 180, a moving unit 190, and a detection unit 200 in a holder 210 as a housing unit. The filter unit 180 includes a 1 st filter 181 as a 1 st region and a 2 nd filter 182 as a 2 nd region, and the moving unit 190 moves the filter unit 180 so that either the 1 st filter 181 or the 2 nd filter 182 is disposed between the imaging element 13 and the opening 15. The detection unit 200 includes a detection light source 201 that emits detection light for detecting the position of the filter unit 180, and a light receiving unit 202 that receives the detection light. The filter control unit 34 included in the control unit 31 of the imaging apparatus 10 causes the detection light source 201 to start emitting the detection light at a predetermined timing, and causes the detection light source 201 to stop emitting the detection light when the detection unit 200 detects that the movement of the filter unit 180 is completed. Accordingly, since the detection unit 200 can be housed inside the holder 210, the imaging device 10 can be prevented from being increased in size, unlike the case where the detection unit 200 is disposed outside the holder 210. Further, since the emission of the detection light from the detection light source 201 and the emission of the detection light stop can be controlled, it is possible to prevent the image quality of the image data generated by the image processing unit 35 from being degraded due to the incidence of the detection light emitted from the detection light source 201 housed in the holder 210 on the imaging element 13 during the imaging operation.

(2) When the brightness change detected by the illuminometer 17 is higher than the threshold brightness or the brightness change detected by the illuminometer 17 is lower than the threshold brightness, the filter control unit 34 causes the detection light source 201 to emit detection light and the moving unit 190 moves the filter unit 180. Thus, since the detection light is emitted from the detection light source 201 at the timing when the imaging mode is switched between the normal imaging mode and the night vision mode, the detection light does not enter the imaging element 13 during imaging, and the image quality of the generated image data can be prevented from being degraded.

(3) The filter control unit 34 synchronizes the emission of the detection light from the detection light source 201 with the movement of the movement unit 190 to start the movement of the filter unit 180, and synchronizes the stop of the emission of the detection light from the detection light source 201 with the completion of the movement unit 190. Thus, the period during which the detection light source 201 emits the detection light coincides with the period during which the filter unit 180 moves, and the detection light source 201 does not emit the detection light during the imaging by the imaging element 13. Therefore, light does not enter the image sensor 13 during shooting, and the image quality of the generated image data can be prevented from being degraded.

While the various embodiments and modifications have been described above, the present invention is not limited to these embodiments. Other modes considered within the scope of the technical idea of the present invention are also included in the scope of the present invention.

The filter control unit 34 may not perform energization to the detection unit 200 and the drive unit 191 synchronously, and may not perform energization to the detection unit 200 and the drive unit 191 synchronously. That is, the filter control unit 34 may perform energization of the detection unit 200 and energization of the drive unit 191 at different timings, or may perform end of energization of the detection unit 200 and end of energization of the drive unit 191 at different timings. When the detection unit 200 and the drive unit 191 are synchronized in energization, the detection unit 200 and the drive unit 191 are connected to the same port of the control unit 31, for example. Thus, the control unit 31 can control the detection unit 200 and the drive unit 191 simultaneously by outputting signals from 1 port.

The filter control unit 34 may energize the detection unit 200 at the timing of switching the imaging mode according to a change in brightness of the external environment, and may cause the detection light source 201 to emit the detection light at predetermined time intervals, in addition to the operation of the embodiment in which the detection light is emitted from the detection light source 201. That is, even when the image capturing is performed in the normal image capturing mode or the night vision mode, the filter control unit 34 detects the position of the holding unit 183 of the filter unit 180 every time a predetermined time elapses by using the detection unit 200. Thus, for example, by applying vibration or the like to the imaging device 10, it is possible to detect a state in which the position of the holding portion 183 is shifted from the 1 st position or the 2 nd position. When the positional deviation of the holding unit 183 as described above is detected, the filter control unit 34 may drive the driving unit 191 to move the holding unit 183 to the 1 st position or the 2 nd position.

Claims (4)

1. An image pickup apparatus includes:

an illumination light source that emits illumination light for illuminating an object;

a filter section having a 1 st region not allowing the illumination light to pass therethrough and a 2 nd region allowing the illumination light to pass therethrough;

a moving unit that moves the filter unit;

a detection unit having a detection light source that emits detection light for detecting a position of the filter unit, and a light receiving unit that receives the detection light;

a housing unit that houses the filter unit, the moving unit, and the detecting unit;

an imaging unit that receives, from among the light that has passed through the opening, light that has passed through the filter unit housed in the housing unit and converts the light into an image signal; and

a control unit that controls start and stop of emission of the detection light from the detection light source,

the moving unit moves the filter unit to dispose one of the 1 st region and the 2 nd region between the imaging unit and the opening,

the control unit causes the detection light source to start emitting the detection light at a predetermined timing, and causes the detection light source to stop emitting the detection light when the movement of the filter unit is completed.

2. The image pickup apparatus according to claim 1,

the imaging device has an illumination unit for detecting brightness of an external environment,

the control unit further controls the movement unit to start and end a movement operation of moving the filter unit,

the control unit causes the detection light source to emit the detection light and causes the moving unit to start the moving operation, with the predetermined timing being set such that the brightness detected by the illumination unit changes to a brightness higher than a threshold value or the brightness detected by the illumination unit changes to a brightness lower than the threshold value.

3. The image pickup apparatus according to claim 2,

the control unit causes the detection light source to start emitting the detection light in synchronization with the movement of the moving unit being started, and causes the detection light source to stop emitting the detection light in synchronization with the movement of the moving unit being ended.

4. The image pickup apparatus according to claim 3,

the detection light source and the moving part are connected with the same port of the control part.

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