JP2021009204A - Control device, imaging apparatus, imaging system, moving body, control method, and program - Google Patents

Abstract

To solve such a problem that there is a case where exposure by automatic exposure control is not always exposure following user's intention.SOLUTION: A control device may be a control device for controlling at least one of a diaphragm value and an exposure time of an imaging apparatus on the basis of a target exposure value of the imaging apparatus. The control device may include a circuit configured so as to change the target exposure value on the basis of the transmittance of light of an optical device transmitting light made incident on an image sensor included in the imaging apparatus. The circuit may be configured so as to acquire instruction data for changing at least one of the diaphragm value and the exposure time of the imaging apparatus, determine a first diaphragm value and a first exposure time on the basis of the instruction data and the target exposure value, change the transmittance of the optical device when the first diaphragm value is not in a predetermined diaphragm value range or the first exposure time is not in a predetermined exposure time range, and change the target exposure value on the basis of the changed transmittance of the optical device.SELECTED DRAWING: Figure 3

Description

The present invention relates to a control device, an image pickup device, an image pickup system, a moving body, a control method, and a program.

Patent Document 1 describes that the brightness level of an input image is changed by rotating the PL filter.
[Prior art literature]
[Patent Document]
[Patent Document 1] Japanese Unexamined Patent Publication No. 2014-74838

The exposure by automatic exposure control may not always be the exposure that the user intended.

The control device according to one aspect of the present invention may be a control device that controls at least one of the aperture value and the exposure time of the image pickup device based on the target exposure value of the image pickup device. The control device may include a circuit configured to change the target exposure value based on the light transmittance of the optical device that transmits the light incident on the image sensor included in the image pickup device.

The circuit may be configured to acquire instructional data for changing at least one of the aperture value and the exposure time of the imaging device. The circuit may be configured to determine the first aperture value and the first exposure time based on the indicated data and the target exposure value. The circuit is configured to change the transmittance of the optical device if the first aperture value is not within a predetermined aperture value range or the first exposure time is not within a predetermined exposure time range. Good. The circuit may be configured to change the target exposure value based on the changed transmittance of the optical device.

The circuit may be configured to determine a second aperture value within a predetermined aperture value range and a second exposure time within a predetermined range based on the indicated data and the target exposure value. The circuit may be configured to change the transmittance of the optical device based on the difference between the target exposure value before the change and the exposure value based on the second aperture value and the second exposure time.

The optical device may have a first polarizing filter, a second polarizing filter that overlaps the first polarizing filter in the optical axis direction, and a rotation mechanism for rotating the first polarizing filter. The circuit adjusts the relative positional relationship between the polarization direction of the light passing through the first polarizing filter and the polarization direction of the light passing through the second polarizing filter via the rotation mechanism, thereby adjusting the transmittance of the optical device. It may be configured to change.

The image pickup device may be rotatably supported by a support mechanism. The rotation mechanism may further rotate the second polarizing filter. The circuit maintains the relative positional relationship between the polarization direction of the first polarizing filter and the polarization direction of the second polarizing filter based on the control command for the support mechanism for rotating the image pickup device in the first direction. The rotation mechanism may be controlled so as to rotate the first polarizing filter and the second polarizing filter in the second direction opposite to the first direction.

The circuit changes the transmittance of the optical device at the first speed when the image pickup device captures a still image, and changes the transmittance of the optical device at the second speed slower than the first speed when the image pickup device captures a moving image. It may be configured to change with.

The image pickup apparatus may include the control device, an optical device, and an image sensor.

The imaging system according to one aspect of the present invention may include the imaging apparatus and a support mechanism that rotatably supports the imaging apparatus.

The moving body according to one aspect of the present invention may be a moving body provided with the above-mentioned imaging system.

The control method according to one aspect of the present invention may be a control method that controls at least one of the aperture value and the exposure time of the image pickup device based on the target exposure value of the image pickup device. The control method may include a step of changing the target exposure value based on the light transmittance of the optical device that transmits the light incident on the image sensor included in the image pickup apparatus.

The program according to one aspect of the present invention may be a program for operating a computer as the control device.

According to one aspect of the present invention, it is possible to more easily realize the exposure according to the user's intention.

The outline of the above invention does not list all the necessary features of the present invention. Sub-combinations of these feature groups can also be inventions.

It is a figure which shows an example of the appearance of an unmanned aerial vehicle and a remote control device. It is a figure which shows an example of the functional block of an unmanned aerial vehicle. It is a figure which shows an example of the relationship between the rotation angle of a polarizing filter, and a transmittance. It is a figure which shows an example of the state of the change rate of the transmittance of an optical device when an image pickup apparatus captures a still image, and the change rate of the transmittance of an optical device when an image pickup apparatus captures a moving image. It is a figure which shows an example of the relationship between the number of steps of the drive motor of a polarizing filter drive part, and the polarization plane angle of a polarizing filter. It is a figure which shows the state of driving of the drive motor according to the rotation of an image pickup apparatus. It is a figure which shows an example of a hardware configuration.

Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. Also, not all combinations of features described in the embodiments are essential to the means of solving the invention. It will be apparent to those skilled in the art that various changes or improvements can be made to the following embodiments. It is clear from the description of the claims that such modified or improved forms may also be included in the technical scope of the present invention.

The claims, description, drawings, and abstracts include matters that are subject to copyright protection. The copyright holder will not object to any person's reproduction of these documents as they appear in the Patent Office files or records. However, in other cases, all copyrights are reserved.

Various embodiments of the present invention may be described with reference to flowcharts and block diagrams, wherein the block is (1) a stage of the process in which the operation is performed or (2) a device having a role of performing the operation. May represent the "part" of. Specific stages and "parts" may be implemented by programmable circuits and / or processors. Dedicated circuits may include digital and / or analog hardware circuits. It may include integrated circuits (ICs) and / or discrete circuits. The programmable circuit may include a reconfigurable hardware circuit. Reconfigurable hardware circuits include logical AND, logical OR, logical XOR, logical NAND, logical NOR, and other logical operations, flip-flops, registers, field programmable gate arrays (FPGA), programmable logic arrays (PLA), etc. It may include a memory element such as.

The computer-readable medium may include any tangible device capable of storing instructions executed by the appropriate device. As a result, the computer-readable medium having the instructions stored therein will include the product, including instructions that can be executed to create means for performing the operation specified in the flowchart or block diagram. Examples of computer-readable media may include electronic storage media, magnetic storage media, optical storage media, electromagnetic storage media, semiconductor storage media, and the like. More specific examples of computer-readable media include floppy® disks, diskettes, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), Electrically erasable programmable read-only memory (EEPROM), static random access memory (SRAM), compact disc read-only memory (CD-ROM), digital versatile disc (DVD), Blu-ray (RTM) disc, memory stick, integrated A circuit card or the like may be included.

Computer-readable instructions may include either source code or object code written in any combination of one or more programming languages. Source code or object code includes traditional procedural programming languages. Traditional procedural programming languages include assembler instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state-setting data, or Smalltalk, JAVA®, C ++, etc. It may be an object-oriented programming language, and a "C" programming language or a similar programming language. Computer-readable instructions are used locally or on a local area network (LAN), wide area network (WAN) such as the Internet, to the processor or programmable circuit of a general purpose computer, special purpose computer, or other programmable data processing device. ) May be provided. The processor or programmable circuit may execute computer-readable instructions to create means for performing the operations specified in the flowchart or block diagram. Examples of processors include computer processors, processing units, microprocessors, digital signal processors, controllers, microcontrollers and the like.

FIG. 1 shows an example of the appearance of the unmanned aerial vehicle (UAV) 10 and the remote control device 300. The UAV 10 includes a UAV main body 20, a gimbal 50, a plurality of image pickup devices 60, and an image pickup device 100. The gimbal 50 and the imaging device 100 are examples of an imaging system. The UAV 10 is a concept including a moving body, an air vehicle moving in the air, a vehicle moving on the ground, a ship moving on the water, and the like. An airship that moves in the air is a concept that includes UAVs, other aircraft that move in the air, airships, helicopters, and the like.

The UAV main body 20 includes a plurality of rotor blades. The plurality of rotor blades are an example of a propulsion unit. The UAV main body 20 flies the UAV 10 by controlling the rotation of a plurality of rotor blades. The UAV body 20 flies the UAV 10 using, for example, four rotor blades. The number of rotor blades is not limited to four. Further, the UAV 10 may be a fixed-wing aircraft having no rotor blades.

The imaging device 100 is an imaging camera that captures a subject included in a desired imaging range. The gimbal 50 rotatably supports the imaging device 100. The gimbal 50 is an example of a support mechanism. For example, the gimbal 50 rotatably supports the imaging device 100 on a pitch axis using an actuator. The gimbal 50 further rotatably supports the image pickup device 100 around each of the roll axis and the yaw axis by using an actuator. The gimbal 50 may change the posture of the image pickup device 100 by rotating the image pickup device 100 around at least one of the yaw axis, the pitch axis, and the roll axis.

The plurality of imaging devices 60 are sensing cameras that image the surroundings of the UAV 10 in order to control the flight of the UAV 10. Two imaging devices 60 may be provided in front of the nose of the UAV 10. Yet two other imaging devices 60 may be provided on the bottom surface of the UAV 10. The two image pickup devices 60 on the front side may form a pair and function as a so-called stereo camera. The two imaging devices 60 on the bottom side may also be paired and function as a stereo camera. Three-dimensional spatial data around the UAV 10 may be generated based on the images captured by the plurality of imaging devices 60. The number of image pickup devices 60 included in the UAV 10 is not limited to four. The UAV 10 may include at least one imaging device 60. The UAV 10 may be provided with at least one imaging device 60 on each of the nose, nose, side surface, bottom surface, and ceiling surface of the UAV 10. The angle of view that can be set by the image pickup device 60 may be wider than the angle of view that can be set by the image pickup device 100. The image pickup apparatus 60 may have a single focus lens or a fisheye lens.

The remote control device 300 communicates with the UAV 10 to remotely control the UAV 10. The remote control device 300 may communicate wirelessly with the UAV 10. The remote control device 300 transmits instruction information indicating various commands related to the movement of the UAV 10, such as ascending, descending, accelerating, decelerating, advancing, reversing, and rotating, to the UAV 10. The instruction information includes, for example, instruction information for raising the altitude of the UAV 10. The instruction information may indicate the altitude at which the UAV 10 should be located. The UAV 10 moves so as to be located at an altitude indicated by the instruction information received from the remote control device 300. The instruction information may include an ascending instruction to ascend the UAV 10. The UAV10 rises while accepting the rise order. Even if the UAV10 accepts the ascending command, the ascending may be restricted if the altitude of the UAV10 has reached the upper limit altitude.

FIG. 2 shows an example of the functional block of the UAV 10. The UAV 10 includes a UAV control unit 30, a memory 37, a communication interface 36, a propulsion unit 40, a GPS receiver 41, an inertial measurement unit 42, a magnetic compass 43, a barometric altimeter 44, a temperature sensor 45, a humidity sensor 46, a gimbal 50, and an imaging device. The 60 and the image pickup device 100 are provided.

The communication interface 36 communicates with another device such as the remote control device 300. The communication interface 36 may receive instruction information including various commands from the remote control device 300 to the UAV control unit 30. In the memory 37, the UAV control unit 30 has a propulsion unit 40, a GPS receiver 41, an inertial measurement unit (IMU) 42, a magnetic compass 43, a barometric altimeter 44, a temperature sensor 45, a humidity sensor 46, a gimbal 50, and an imaging device 60. The program and the like necessary for controlling the image pickup device 100 are stored. The memory 37 may be a computer-readable recording medium and may include at least one of flash memory such as SRAM, DRAM, EPROM, EEPROM, USB memory, and solid state drive (SSD). The memory 37 may be provided inside the UAV main body 20. It may be provided so as to be removable from the UAV main body 20.

The UAV control unit 30 controls the flight and imaging of the UAV 10 according to the program stored in the memory 37. The UAV control unit 30 may be composed of a CPU, a microprocessor such as an MPU, a microcontroller such as an MCU, or the like. The UAV control unit 30 controls the flight and imaging of the UAV 10 according to a command received from the remote control device 300 via the communication interface 36. The propulsion unit 40 promotes the UAV 10. The propulsion unit 40 has a plurality of rotary blades and a plurality of drive motors for rotating the plurality of rotary blades. The propulsion unit 40 makes the UAV 10 fly by rotating a plurality of rotor blades via the plurality of drive motors in accordance with a command from the UAV control unit 30.

The GPS receiver 41 receives a plurality of signals indicating the time transmitted from the plurality of GPS satellites. The GPS receiver 41 calculates the position (latitude and longitude) of the GPS receiver 41, that is, the position (latitude and longitude) of the UAV 10 based on the plurality of received signals. The IMU 42 detects the posture of the UAV 10. The IMU 42 detects the acceleration in the three axial directions of the front-back, left-right, and up-down of the UAV 10 and the angular velocity in the three-axis directions of pitch, roll, and yaw as the posture of the UAV 10. The magnetic compass 43 detects the nose orientation of the UAV 10. The barometric altimeter 44 detects the altitude at which the UAV 10 flies. The barometric altimeter 44 detects the barometric pressure around the UAV 10, converts the detected barometric pressure into an altitude, and detects the altitude. The temperature sensor 45 detects the ambient temperature of the UAV 10. The humidity sensor 46 detects the humidity around the UAV 10.

The image pickup apparatus 100 includes an image pickup section 102 and a lens section 200. The lens unit 200 is an example of a lens device. The image pickup unit 102 includes an image sensor 120, an image pickup control unit 110, a memory 130, and an acceleration sensor 140. The image sensor 120 may be configured by CCD or CMOS. The image sensor 120 captures an optical image formed through a plurality of lenses 210, and outputs the captured image to the image pickup control unit 110. The image pickup control unit 110 may be composed of a CPU, a microprocessor such as an MPU, a microcontroller such as an MCU, or the like. The image pickup control unit 110 is an example of a circuit. The image pickup control unit 110 may control the image pickup device 100 in response to an operation command of the image pickup device 100 from the UAV control unit 30. The image pickup control unit 110 is an example of the first control unit and the second control unit. The memory 130 may be a computer-readable recording medium and may include at least one of flash memory such as SRAM, DRAM, EPROM, EEPROM, USB memory, and solid state drive (SSD). The memory 130 stores a program or the like necessary for the image pickup control unit 110 to control the image sensor 120 or the like. The memory 130 may be provided inside the housing of the image pickup apparatus 100. The memory 130 may be provided so as to be removable from the housing of the image pickup apparatus 100.

The acceleration sensor 140 detects acceleration in three axial directions: front-back, left-right, and up-down of the image pickup device 100. The image pickup control unit 110 acquires information indicating acceleration in the three axial directions of the front / rear, left / right, and up / down of the image pickup device 100 from the acceleration sensor 140 as posture information indicating the posture state of the image pickup device 100.

The lens unit 200 includes a plurality of lenses 210, a plurality of lens driving units 212, and a lens control unit 220. The plurality of lenses 210 may function as a zoom lens, a varifocal lens, and a focus lens. At least a part or all of the plurality of lenses 210 are arranged so as to be movable along the optical axis. The lens unit 200 may be an interchangeable lens that is detachably provided to the imaging unit 102. The lens driving unit 212 moves at least a part or all of the plurality of lenses 210 along the optical axis via a mechanical member such as a cam ring. The lens driving unit 212 may include an actuator. The actuator may include a stepping motor. The lens control unit 220 drives the lens drive unit 212 in accordance with a lens control command from the image pickup unit 102 to move one or more lenses 210 along the optical axis direction via a mechanical member. The lens control command is, for example, a zoom control command and a focus control command.

The lens unit 200 further includes a memory 222 and a position sensor 214. The lens control unit 220 controls the movement of the lens 210 in the optical axis direction via the lens drive unit 212 in response to a lens operation command from the image pickup unit 102. The lens control unit 220 controls the movement of the lens 210 in the optical axis direction via the lens drive unit 212 in response to a lens operation command from the image pickup unit 102. Part or all of the lens 210 moves along the optical axis. The lens control unit 220 executes at least one of the zoom operation and the focus operation by moving at least one of the lenses 210 along the optical axis. The position sensor 214 detects the position of the lens 210. The position sensor 214 may detect the current zoom position or focus position.

The lens driving unit 212 may include a runout correction mechanism. The lens control unit 220 may execute the shake correction by moving the lens 210 in the direction along the optical axis or in the direction perpendicular to the optical axis via the shake correction mechanism. The lens driving unit 212 may drive the runout correction mechanism by a stepping motor to perform runout correction. The runout correction mechanism may be driven by a stepping motor to move the image sensor 120 in a direction along the optical axis or in a direction perpendicular to the optical axis to perform runout correction.

The memory 222 stores the control values of the plurality of lenses 210 that move via the lens driving unit 212. The memory 222 may include at least one of flash memories such as SRAM, DRAM, EPROM, EEPROM, and USB memory.

The lens unit 200 further includes an optical device 230. The optical device 230 may be a variable ND filter whose transmittance can be changed. The optical device 230 includes a polarizing filter driving unit 232, a polarizing filter 234, and a polarizing filter 236. The polarizing filter 234 and the polarizing filter 236 are optical filters that transmit light in a specific polarization direction. The polarizing filter 234 and the polarizing filter 236 may be arranged on the optical axis of the image pickup apparatus 100.

The polarizing filter 234 and the polarizing filter 236 may be arranged between the lens 210 and the image sensor 120. The polarizing filter driving unit 232 includes a rotation mechanism for rotating the polarizing filter 234. The polarizing filter driving unit 232 may rotate the polarizing filter 234 about the optical axis. The polarizing filter drive unit 232 includes a drive motor. The rotating mechanism may include at least one gear that transmits power from the drive motor to the polarizing filter 234. The drive motor may be a stepping motor. The polarizing filter driving unit 232 changes the polarization direction of the light passing through the polarizing filter 234 by rotating the polarizing filter 234. The polarizing filter 236 may be fixed on the optical axis. The polarizing filter driving unit 232 includes a rotation detection sensor that detects the rotation of the polarizing filter 234. The rotation detection sensor may be a photo interrupter, a variable resistor, a Hall element, or the like.

The polarizing filter driving unit 232 changes the polarization direction of the light transmitted through the polarizing filter 234 in the absolute space, that is, in the real space by rotating the polarizing filter 234. The polarizing filter 234 changes the angle of the plane of polarization of light passing through the polarizing filter 234 in real space. The polarizing filter driving unit 232 changes the rotation angle of the polarizing filter 234 by rotating the polarizing filter 234, and changes the polarization direction of the light transmitted through the polarizing filter 234. The optical device 230 can change the transmittance of the optical device 230 by adjusting the relative positional relationship between the polarization direction of the polarizing filter 234 and the polarization direction of the polarizing filter 236. The optical device 230 may be another type of filter whose light transmittance can be electrically adjusted as long as it is a variable ND filter. The optical device 230 may be, for example, an electrochromic element. Electrochromic devices include electromic materials in which optical absorption is reversibly generated by applying a voltage or passing an electric current. The optical device 230 may be a liquid crystal type ND filter whose transmittance can be adjusted by changing the liquid crystal arrangement by applying a voltage.

The imaging unit 102 includes a photometric sensor 150. The photometric sensor 150 detects the amount of light passing through the lens 210. The photometric sensor 150 is a TTL exposure meter. The image pickup control unit 110 includes an automatic exposure control unit 112 and a transmittance control unit 114. The automatic exposure control unit 112 executes automatic exposure control by controlling the aperture and the shutter. The transmittance control unit 114 controls the polarizing filter drive unit 232 to control the transmittance of the optical device 230.

The automatic exposure control unit 112 determines a target exposure value (EV value), which is an appropriate exposure, based on the amount of light detected by the photometric sensor 150. The automatic exposure control unit 112 determines the aperture value of the aperture and the shutter speed (exposure time) of the shutter based on the target exposure value. The automatic exposure control unit 112 determines the AV value, which is an index of the aperture value, and the TV value, which is an index of the shutter speed, based on the target exposure value. The automatic exposure control unit 112 controls the aperture based on the AV value and controls the shutter speed based on the TV value. The automatic exposure control unit 112 may control the exposure value so that the exposure value becomes appropriate by adjusting the ISO sensitivity.

By the way, the image captured by the aperture value (AV value) and the shutter speed (TV value) determined by the automatic exposure control unit 112 is not always the image intended by the user. For example, when an image pickup device 100 captures a moving image, the shutter speed determined by the automatic exposure control unit 112 may be too fast, resulting in an unsmooth, flip book-like image.

In the above cases, it is conceivable to slow down the shutter speed and lengthen the exposure time. In this case, if the aperture value is increased, the exposure may be appropriate. For example, it is assumed that the EV value of proper exposure is set to 14, the AV value is set to 6, and the TV value is set to 8 by automatic exposure control. At this time, the TV value is set to 6 in order to slow down the shutter speed. Since the sum of the AV value and the TV value is the EV value (EV value = AV value + TV value), in this case, if the AV value can be set to 8, the proper exposure will be obtained. However, there are times when you do not want to change the aperture value in order to obtain the image that the user intended. That is, there are cases where the AV value is not set to 8. In this case, if the shutter speed is slowed down, the image pickup apparatus 100 cannot take an image with proper exposure.

Therefore, in the present embodiment, the transmittance control unit 114 adjusts the transmittance of the optical device 230. When the AV value cannot be set from 6 to 8, the transmittance control unit 114 adjusts the transmittance of the optical device 230 so that the amount of light incident on the image sensor 120 is darkened by two steps. Thereby, for example, even if the aperture value is not changed and the shutter speed is slowed down, the image pickup apparatus 100 can take an image having the same brightness as the image taken with the proper exposure.

The image pickup control unit 110 determines a target exposure value for proper exposure based on the amount of light from the photometric sensor 150 and the set ISO sensitivity. The image pickup control unit 110 changes the target exposure value based on the light transmittance of the optical device 230 that transmits the light incident on the image sensor 120. The image pickup control unit 110 acquires instruction data for changing at least one of the aperture value and the exposure time. The image pickup control unit 110 acquires instruction data from the user. The image pickup control unit 110 acquires instruction data via the remote control device 300. The image pickup control unit 110 acquires, for example, instruction data for changing the TV value from "8" to "6" as instruction data.

The automatic exposure control unit 112 determines the first aperture value and the first exposure time based on the instruction data and the target exposure value. For example, the automatic exposure control unit 112 determines the TV value specified by the instruction data as the first exposure time, and determines the AV value at which the proper exposure can be obtained with the TV value as the first aperture value.

The transmittance control unit 114 changes the transmittance of the optical device 230 when the first aperture value is not within the predetermined aperture value range or the first exposure time is not within the predetermined exposure time range. .. For example, when the aperture value is fixed, the transmittance control unit 114 determines that the first aperture value is not within the predetermined aperture value range because the AV value cannot be changed with the change of the TV value. The predetermined aperture value range and the predetermined exposure time range may be set by the user, or may be set according to a shooting mode such as aperture priority or shutter priority. The predetermined aperture value range may be an AV value having a plurality of stages, for example, a range from a first AV value to a second EV value, or an AV value of any one stage. The predetermined exposure time range may be a TV value having a plurality of stages, for example, a range from a first TV value to a second TV value, or a TV value of any one stage.

When the first aperture value is not within the predetermined aperture value range, the transmittance control unit 114 sets the second aperture value within the predetermined aperture value range and the predetermined aperture value based on the instruction data and the target exposure value. The second exposure time within the defined range is determined. For example, when the aperture value is fixed, the transmittance control unit 114 determines the TV value indicated in the instruction data as the second exposure time, and determines the current AV value as the second aperture value. The transmittance control unit 114 changes the transmittance of the optical device 230 based on the difference between the target exposure value before the change and the exposure value based on the second aperture value and the second exposure time. The transmittance control unit 114 changes the transmittance of the optical device 230 based on the number of steps of the difference between the target exposure value before the change and the exposure value based on the second aperture value and the second exposure time. .. The transmittance control unit 114 changes the transmittance of the optical device 230 so that the transmittance corresponds to the number of stages of the difference.

For example, when the target exposure value before the change is "14", the AV value corresponding to the second aperture value is "6", and the TV value corresponding to the second exposure time is "6", the second The exposure value based on the aperture value and the second exposure time is "12". Since the transmittance control unit 114 has a large amount of light input to the image sensor 120 by "2" stages, the optical device 230 has a small amount of light input to the image sensor 120 by "2" stages. Change the transmittance of. The transmittance control unit 114 changes the transmittance of the optical device 230 by controlling the rotation angle of the polarizing filter 234.

The automatic exposure control unit 112 changes the target exposure value based on the changed transmittance of the optical device 230. For example, the automatic exposure control unit 112 changes the target exposure value from "14" to "12" based on the changed transmittance of the optical device 230. As a result, the image pickup apparatus 100 can capture an image having the same brightness as when the target exposure value is “14”.

FIG. 3 shows an example of the relationship between the rotation angle of the polarizing filter 234 and the transmittance K. The transmittance control unit 114 can change the proper exposure by changing the transmittance K of the optical device 230. For example, by lowering the transmittance K, the EV value for proper exposure can be reduced.

FIG. 4 shows an example of the change rate of the transmittance of the optical device 230 when the image pickup device 100 captures a still image, and the change rate of the transmittance of the optical device 230 when the image pickup device 100 captures a moving image. It is a figure which shows. If the transmittance of the optical device 230 changes abruptly when the image pickup apparatus 100 captures a moving image, the image may flicker and the image may be adversely affected. Therefore, the transmittance control unit 114 changes the transmittance of the optical device 230 at the first speed when the imaging device 100 captures a still image, and when the imaging device 100 captures a moving image, the transmittance of the optical device 230. May be changed at a second speed slower than the first speed.

By the way, the posture of the image pickup apparatus 100 changes with time as the posture of the UAV 10 changes with time. When the posture of the image pickup apparatus 100 changes, the polarization direction of the light passing through the polarizing filter 234 and the polarizing filter 236 changes. When the polarization direction changes, the intensity of light in a specific polarization direction incident on the image sensor 120 may change. For example, the intensity of sunlight reflected on the water surface incident on the image sensor 120 may change. That is, there is a possibility that the image pickup device 100 cannot capture an image of a style according to the user's intention.

Here, the polarizing filter driving unit 232 may rotate the polarizing filter 236 about the optical axis in addition to the polarizing filter 234. In this case, it is conceivable to detect the posture of the imaging device 100 and change the rotation angles of the polarizing filter 234 and the polarizing filter 236 according to the posture of the imaging device 100. However, when the rotation angles of the polarizing filter 234 and the polarizing filter 236 are changed by feedback as in this method, the rotation angles of the polarizing filter 234 and the polarizing filter 236 are not necessarily changed when the posture of the imaging device 100 changes with time. Cannot be controlled properly.

Therefore, the transmittance control unit 114 rotates the rotation angles of the polarizing filter 234 and the polarizing filter 236 by feed forward while maintaining the relative positional relationship between the polarization direction of the polarizing filter 234 and the polarization direction of the polarizing filter 236. You may let me.

The transmission control unit 114 sets the image pickup device 100 in the first direction to the gimbal 50 that rotatably supports the image pickup device 100 while maintaining the relative positional relationship between the polarizing filter 234 and the polarizing filter 236 in the polarization direction. The polarizing filter driving unit 232 may be controlled so as to rotate the polarizing filter 234 and the polarizing filter 236 in the second direction opposite to the first direction based on the control command for rotation. The transmittance control unit 114 may control the polarizing filter driving unit 232 so as to rotate the polarizing filter 234 in the second direction by the amount of rotation of the imaging device 100 in the first direction based on the control command. The transmittance control unit 114 is based on a control command for rotating the image pickup device 100 in the first direction to the gimbal 50 that rotatably supports the image pickup device 100 while maintaining the transmittance of the optical device 230. The polarizing filter driving unit 232 may be controlled so as to rotate the polarizing filter 234 and the polarizing filter 236 in the second direction opposite to the first direction.

FIG. 5 shows the relationship between the number of steps of the drive motor of the polarizing filter driving unit 232 and the polarization plane angle of the polarizing filter 234. The polarization plane angle of the polarizing filter 234 is an angle formed by the polarization plane of light passing through the polarizing filter 234 and the horizontal plane of the image pickup apparatus 100. The polarization plane is a plane including the polarization direction. The horizontal plane of the image pickup apparatus 100 may be a plane including the optical axis when the image pickup apparatus 100 is in the reference posture (the optical axis is oriented in the horizontal direction).

As the number of steps increases, the polarizing filter 234 and the polarizing filter 236 rotate in the first direction (positive direction). When the number of steps of the drive motor is + N, the rotation angles of the polarizing filter 234 and the polarizing filter 236 become +180 degrees. On the other hand, when the number of steps of the drive motor is −N, the rotation angles of the polarizing filter 234 and the polarizing filter 236 are −180 degrees.

FIG. 6 shows how the drive motor is driven according to the rotation of the image pickup apparatus 100. The state in which the image pickup apparatus 100 is imaging a subject while the UAV 10 is flying is shown. In step 1, the flight state of the UAV 10 is horizontal to the ground, and the attitude state of the image pickup device 100 supported by the gimbal 50 is also horizontal to the ground. That is, the plane including the optical axis of the image pickup apparatus 100 and the ground are parallel. In this state, the UAV control unit 30 outputs a control command to the gimbal 50 to rotate the posture state of the image pickup apparatus 100 with respect to the ground by +30 degrees around the optical axis. As a result, the process proceeds from step 1 to step 2.

In step 2, the imaging control unit 110 adjusts the polarizing filter 234 and the polarizing filter 236 by -30 degrees (in synchronization with the control command) while maintaining the relative positional relationship between the polarizing filter 234 and the polarizing filter 236 in the polarization direction. It outputs a rotation drive command to the drive motor to rotate by −N / 6 steps). As a result, the polarization direction of the light passing through the polarizing filter 234 and the polarizing filter 236 can be maintained. That is, the rotation angles of the polarizing filter 234 and the polarizing filter 236 can be maintained at a constant angle with respect to the ground while maintaining the transmittance of the optical device 230.

Next, in step 3, the flight state of the UAV 10 is horizontal with respect to the ground, and the attitude state of the image pickup device 100 supported by the gimbal 50 is rotated about the optical axis by −30 degrees with respect to the ground.

In step 3, the UAV control unit 30 outputs a control command to the gimbal 50 to rotate the posture state of the image pickup apparatus 100 with respect to the ground by +30 degrees to -30 degrees around the optical axis. The imaging control unit 110 drives a rotation drive command that rotates the polarizing filter 234 and the polarizing filter 236 by -30 degrees to +30 degrees (from −N / 6 steps to + N / 6 steps) in synchronization with this control command. Output to. As a result, the image pickup apparatus 100 rotates in the second direction (negative direction) about the optical axis at a constant rotation speed. Therefore, the polarization direction of the light passing through the polarizing filter 234 and the polarizing filter 236 can be maintained. That is, the rotation angles of the polarizing filter 234 and the polarizing filter 236 can be maintained at a constant angle with respect to the ground while maintaining the transmittance of the optical device 230.

After that, the gimbal 50 controls the posture state of the image pickup apparatus 100 to be horizontal with respect to the ground. During this period, the imaging control unit 110 maintains the relative positional relationship between the polarizing filter 234 and the polarizing filter 236 in the polarization direction, and for example, the rotation angle of the polarizing filter 234 is horizontal (0) with respect to the ground. The drive motor is driven so as to be (degree).

As described above, the imaging control unit 110 rotates the polarizing filter 234 and the polarizing filter 236 by feedforward according to the control command for the gimbal 50. As a result, the polarization directions of the polarizing filter 234 and the polarizing filter 236 can be maintained in a constant direction with respect to the ground while maintaining the transmittance of the optical device 230. Therefore, it is possible to prevent the polarizing device 100 from being unable to capture an image having a style according to the user's intention due to a change in the polarization directions of the polarizing filter 234 and the polarizing filter 236 due to the change in the posture of the imaging device 100.

FIG. 7 shows an example of a computer 1200 in which a plurality of aspects of the present invention may be embodied in whole or in part. The program installed on the computer 1200 can cause the computer 1200 to function as an operation associated with the device according to an embodiment of the present invention or as one or more "parts" of the device. Alternatively, the program may cause the computer 1200 to perform the operation or one or more "parts". The program can cause a computer 1200 to perform a process or a step of the process according to an embodiment of the present invention. Such a program may be run by the CPU 1212 to cause the computer 1200 to perform certain operations associated with some or all of the blocks in the flowcharts and block diagrams described herein.

The computer 1200 according to this embodiment includes a CPU 1212 and a RAM 1214, which are connected to each other by a host controller 1210. The computer 1200 also includes a communication interface 1222, an input / output unit, which are connected to the host controller 1210 via an input / output controller 1220. The computer 1200 also includes a ROM 1230. The CPU 1212 operates according to the programs stored in the ROM 1230 and the RAM 1214, thereby controlling each unit.

Communication interface 1222 communicates with other electronic devices via a network. A hard disk drive may store programs and data used by the CPU 1212 in the computer 1200. The ROM 1230 stores in it a boot program or the like executed by the computer 1200 at the time of activation, and / or a program depending on the hardware of the computer 1200. The program is provided via a computer-readable recording medium such as a CR-ROM, USB stick or IC card or network. The program is installed in RAM 1214 or ROM 1230, which is also an example of a computer-readable recording medium, and is executed by CPU 1212. The information processing described in these programs is read by the computer 1200 and provides a link between the program and the various types of hardware resources described above. The device or method may be configured to implement the operation or processing of information according to the use of the computer 1200.

For example, when communication is executed between the computer 1200 and an external device, the CPU 1212 executes a communication program loaded in the RAM 1214, and performs communication processing on the communication interface 1222 based on the processing described in the communication program. You may order. Under the control of the CPU 1212, the communication interface 1222 reads the transmission data stored in the transmission buffer area provided in the RAM 1214 or a recording medium such as a USB memory, and transmits the read transmission data to the network, or The received data received from the network is written to the reception buffer area or the like provided on the recording medium.

Further, the CPU 1212 makes the RAM 1214 read all or necessary parts of a file or a database stored in an external recording medium such as a USB memory, and executes various types of processing on the data on the RAM 1214. Good. The CPU 1212 may then write back the processed data to an external recording medium.

Various types of information such as various types of programs, data, tables, and databases may be stored in recording media and processed. The CPU 1212 describes various types of operations, information processing, conditional judgment, conditional branching, unconditional branching, and information retrieval described in various parts of the present disclosure with respect to the data read from the RAM 1214, and is specified by the instruction sequence of the program. Various types of processing may be performed, including / replacement, etc., and the results are written back to the RAM 1214. Further, the CPU 1212 may search for information in a file, a database, or the like in the recording medium. For example, when a plurality of entries each having an attribute value of the first attribute associated with the attribute value of the second attribute are stored in the recording medium, the CPU 1212 specifies the attribute value of the first attribute. Search for an entry that matches the condition from the plurality of entries, read the attribute value of the second attribute stored in the entry, and associate it with the first attribute that satisfies the predetermined condition. The attribute value of the second attribute obtained may be acquired.

The program or software module described above may be stored on a computer 1200 or in a computer readable storage medium near the computer 1200. Also, a recording medium such as a hard disk or RAM provided in a dedicated communication network or a server system connected to the Internet can be used as a computer-readable storage medium, thereby allowing the program to be transferred to the computer 1200 over the network. provide.

The execution order of each process such as operation, procedure, step, and step in the device, system, program, and method shown in the claims, the specification, and the drawing is particularly "before" and "prior to". It should be noted that it can be realized in any order unless the output of the previous process is used in the subsequent process. Even if the scope of claims, the specification, and the operation flow in the drawings are explained using "first", "next", etc. for convenience, it means that it is essential to carry out in this order. It's not a thing.

Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various changes or improvements can be made to the above embodiments. It is clear from the description of the claims that such modified or improved forms may also be included in the technical scope of the present invention.

10 UAV
20 UAV body 30 UAV control unit 36 Communication interface 37 Memory 40 Propulsion unit 41 GPS receiver 42 Inertial measurement unit 43 Magnetic compass 44 Atmospheric pressure sensor 45 Temperature sensor 46 Humidity sensor 50 Gimbal 60 Imaging device 100 Imaging device 102 Imaging unit 110 Imaging control unit 112 Automatic exposure control unit 114 Transmission control unit 120 Image sensor 130 Memory 140 Acceleration sensor 150 Photometric sensor 200 Lens unit 210 Lens 212 Lens drive unit 214 Position sensor 220 Lens control unit 222 Memory 230 Optical device 232 Polarization filter drive unit 234, 236 Polarizing filter 300 Remote control device 1200 Computer 1210 Host controller 1212 CPU
1214 RAM
1220 Input / Output Controller 1222 Communication Interface 1230 ROM

Claims (11)

A control device that controls at least one of the aperture value and the exposure time of the image pickup device based on the target exposure value of the image pickup device.
A control device including a circuit configured to change the target exposure value based on the light transmittance of an optical device that transmits light incident on an image sensor included in the image pickup device. The circuit
Obtaining instruction data for changing at least one of the aperture value and the exposure time of the imaging device,
The first aperture value and the first exposure time are determined based on the indicated data and the target exposure value.
If the first aperture value is not within the predetermined aperture value range, or the first exposure time is not within the predetermined exposure time range, the transmittance of the optical device is changed.
The control device according to claim 1, wherein the target exposure value is changed based on the changed transmittance of the optical device. The circuit
Based on the instruction data and the target exposure value, the second aperture value within the predetermined aperture value range and the second exposure time within the predetermined range are determined.
A claim configured to change the transmittance of the optical device based on the difference between the target exposure value before the change and the exposure value based on the second aperture value and the second exposure time. Item 2. The control device according to item 2. The optical device includes a first polarizing filter, a second polarizing filter that overlaps the first polarizing filter in the optical axis direction, and a rotation mechanism for rotating the first polarizing filter.
The circuit adjusts the relative positional relationship between the polarization direction of the light transmitted through the first polarizing filter and the polarization direction of the light transmitted through the second polarizing filter via the rotation mechanism, thereby performing the optics. The control device according to claim 1, wherein the control device is configured to change the transmittance of the device. The image pickup device is rotatably supported by a support mechanism.
The rotation mechanism further rotates the second polarizing filter.
The circuit has a relative positional relationship between the polarization direction of the first polarizing filter and the polarization direction of the second polarizing filter, based on a control command for the support mechanism for rotating the image pickup apparatus in the first direction. 4. The fourth aspect of claim 4, wherein the rotation mechanism is controlled so as to rotate the first polarizing filter and the second polarizing filter in a second direction opposite to the first direction. Control device. The circuit changes the transmittance of the optical device at the first speed when the imaging device captures a still image, and changes the transmittance of the optical device at the first speed when the imaging device captures a moving image. The control device according to claim 1, wherein the control device is configured to change at a slower second speed. The control device according to any one of claims 1 to 6.
An imaging device including the optical device and the image sensor. The imaging device according to claimant 7 and
An imaging system including a support mechanism that rotatably supports the imaging device. A moving body that moves with the imaging system according to claim 8. A control method for controlling at least one of the aperture value and the exposure time of the image pickup apparatus based on the target exposure value of the image pickup apparatus.
A control method including a step of changing an exposure value of a target based on the light transmittance of an optical device that transmits light incident on an image sensor included in the image pickup apparatus. A program for operating a computer as a control device according to any one of claims 1 to 6.

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