JP2015126427A - Imaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem in that, if an optical filter is switched without taking account of a setting condition for a camera, a switching operation for the optical filter is reflected in a photographed image.SOLUTION: An imaging apparatus comprises: a plurality of optical filters; an electrically switching device that is able to switch the optical filter to an arbitrary optical filter by an electrically driving means: operating means that instructs to switch the optical filter; storage means that stores a switching time for the optical filter in advance; and control means that receives the switching instruction and instructs to start the switching operation of the optical filter. The timing of the switching operation of the optical filter is determined from: a switching time stored by the storage means; an exposure time for a first photographing frame, in a series of photographic frames, photographed by the imaging device; and non-exposure time between the first photographing frame and second photographing frame.

Description

  The present invention relates to an imaging device having an optical filter switching structure.

  The existing image pickup apparatus has a structure that appropriately adjusts the amount of light incident on the image pickup sensor so that whiteout or blackout does not occur in a captured image. One of these structures is an ND filter that reduces the amount of light. In an imaging apparatus incorporating a plurality of ND filters, when the ND filter is switched during moving image shooting, the switching operation is reflected in the captured video. The fewer the frames of this reflection, the lower the discomfort of the video due to the reflection, and the more still images that can be cut out from the moving image. An imaging apparatus that includes a plurality of ND filters on a turret, rotates the turret by a switching lever, and switches the ND filter has been proposed (Patent Document 1).

JP 2010-61002 A

  However, the conventional example of Patent Document 1 has a problem that the switching operation is reflected during switching of the ND filter.

The imaging device of the present invention includes a plurality of optical filters,
An electric switching device capable of switching the optical filter to an arbitrary optical filter by electric driving means;
Operating means for instructing switching of the optical filter;
Storage means for storing in advance the switching time of the optical filter;
Control means for receiving the switching instruction and instructing to start the switching operation of the optical filter;
In an imaging apparatus having
The control means includes
Switching time stored by the storage means;
In successive shooting frames that the imaging device is shooting,
The exposure time of the first frame,
The timing of the switching operation of the optical filter is determined from the non-exposure time between the first photographing frame and the second photographing frame.

Another feature of the present invention is that
When an instruction to switch the optical filter is issued by the operating means,
When the non-exposure time is longer than the switching time,
The optical filter switching operation is instructed after the exposure of the first photographing frame is completed.

Another feature of the present invention is that
The control means includes
A flag is set on the second photographing frame.

Another feature of the present invention is that
When an instruction to switch the optical filter is issued by the operating means,
When the exposure time is longer than the switching time,
The optical filter switching operation is instructed after the exposure of the first photographing frame is started.
The control means includes
The first shooting frame is flagged.

  According to the present invention, the switching operation of the optical filter is not reflected in the captured moving image, or the number of frames to be reflected can be minimized.

It is the perspective view seen from the image pick-up device front view which showed the image pick-up device provided with the switching device of the optical filter concerning the embodiment of the present invention. It is the disassembled perspective view seen from the image pick-up device front view which showed the image pick-up device provided with the switching device of the optical filter concerning the embodiment of the present invention. FIG. 5 is a photographic image that sequentially shows how the optical filter switching structure according to the embodiment of the present invention is reflected in a photographic image. FIG. 1 is a system block diagram of an imaging apparatus including an optical filter switching device according to an embodiment of the present invention. It is a flowchart of the switching control of the optical filter which concerns on embodiment of this invention.

<First Embodiment>
FIG. 1 is a perspective view of an imaging apparatus provided with an optical filter switching device according to an embodiment of the present invention, as viewed from the front of the imaging apparatus. Exterior parts are indicated by solid lines, and internal parts are indicated by dotted lines.

  FIG. 2 is an exploded perspective view of the image pickup apparatus including the optical filter switching device according to the embodiment of the present invention, as viewed from the front of the image pickup apparatus. The imaging apparatus 100 includes a lens mount 120, an imaging element unit 130, a substrate 140, an optical filter changeover switch 150, and an optical filter changeover apparatus 200. The lens mount 120 is disposed in front of the imaging apparatus 100, and a lens (not shown) can be exchanged.

  The image sensor unit 130 includes an image sensor 131. The image sensor unit 130 is disposed at a position where light incident from the lens forms an image on the imaging surface 132 of the image sensor 131. Further, the image sensor unit 130 converts the formed image into image data. A CPU (not shown) mounted on the substrate 140 performs optical filter switching control. Further, the image data from the image sensor unit 130 is processed. When pressed, the optical filter changeover switch 150 issues an instruction to switch the optical filter to the substrate 140 to a CPU (not shown) mounted on the substrate 140.

  The optical filter switching device 200 includes an optical filter 201, a motor unit 220, and a rotating plate 210. The optical filter 201 includes a first optical filter 202, a second optical filter 203, and a third optical filter 204. Each optical glass has the same material and thickness, but different light transmittance. The first optical filter 202 is a transparent glass having a light transmittance of 100%, the second optical filter 203 is a neutral density filter having a light transmittance of 12.5%, and the third optical filter 204 is a light transmittance of 1. .56% neutral density filter.

  Light incident from the lens passes through the optical filter 201 and enters the imaging surface 132 of the imaging element 131. The motor unit 220 includes a motor 221 and a gear member 222. The motor 221 converts the power supplied from the substrate 140 into motive power. The gear member 222 is directly connected to the motor 221. The rotating plate 210 includes a center hole portion 211, a gear portion 212, a first arm portion 213, a second arm portion 214, and a third arm portion 215.

  The center hole 211 is the rotation center of the rotating plate 210. The rotating plate 210 rotates around the central hole 211 with the optical axis direction as the central axis direction. The center of the optical axis refers to the center of the optical path incident from the lens, and is indicated by a one-dot chain line in FIG. The gear member 222 supplies the power of the motor 221 to the gear portion 212 of the rotating plate 210 and rotates the rotating plate 210. When viewed from the front of the imaging apparatus 100, the optical filter 201 is held in the order of the first optical filter 202, the second optical filter 203, and the third optical filter 204 in the clockwise direction of the rotating plate 210.

  The first arm portion 213 refers to a part of the rotating plate 210 that exists between the first optical filter 202 and the second optical filter 203. The second arm portion 214 refers to a part of the rotating plate 210 existing between the second optical filter 203 and the third optical filter 204. The third arm portion 215 indicates a part of the rotating plate 210 that exists between the third optical filter 204 and the first optical filter 202.

  FIG. 3 is a system block diagram of an imaging apparatus including an optical filter switching device according to an embodiment of the present invention. When the optical filter changeover switch 150 of the image pickup apparatus 300 is pressed, the CPU 310 on the substrate 140 receives an instruction to change the optical filter at the change instruction receiving unit 311. After that, the switching timing determination unit 312 determines the timing for switching the optical filter 201. Details of the determination method will be described later. After the timing is determined, when a switching operation of the optical filter 201 is instructed from the switching operation instruction unit 313, power is supplied from the substrate 310 to the motor 221 of the optical filter switching device 200 to perform the switching operation of the optical filter.

  4A to 4D are diagrams sequentially showing images formed on the image sensor when switching from the first optical filter 202 to the second optical filter 203 according to the embodiment of the present invention. is there. FIG. 4A shows an image formed on the image sensor 131 when the light incident from the lens is transmitted through the first optical filter 202. FIG. 4B shows an image formed on the image sensor 131 when the optical filter 201 starts to be switched from the first optical filter 202 to the second optical filter 203. The rotating plate 210 provided with the optical filter 201 is rotated in the direction of the arrow in the figure. From the figure, it can be seen that the first arm portion 213 of the rotating plate 210 of the optical filter switching device 200 is greatly reflected. The second optical filter 203 enters from the upper right part of the image.

  FIG. 4C is an image formed on the image sensor 131 when the switching operation further proceeds from FIG. The rotating plate 210 rotates in the direction of the arrow in the figure. As in FIG. 4B, the first arm 213 is greatly reflected. FIG. 4D shows an image formed on the image sensor 131 when the light incident from the lens is transmitted through the second optical filter 203.

  The above is the process in which the first arm 213 is reflected in the image formed on the image sensor 131 when the optical filter is switched.

  As can be seen from FIG. 4B and FIG. 4C, in the optical filter switching operation in the conventional imaging device, when the optical filter 201 is switched during the exposure of the imaging device 131, a part of the optical filter switching device 200 is obtained. Will be recorded as an image. In the present invention, this reflection can be avoided.

  FIG. 5 is a flowchart of optical filter switching control according to the embodiment of the present invention. Note that this flowchart is a flowchart only when the optical filter switch SW is pressed, and a flowchart when the optical filter switch SW is not pressed is omitted. The start of shooting indicates that the imaging apparatus 100 has started recording a moving image. After shooting is started (S100), the settings (exposure time, non-exposure time, switching time) of the imaging apparatus 100 are confirmed (S101). At this time, the imaging apparatus 100 stores the time from the start of the switching operation of the optical filter 201 to the end of the switching operation.

  In the setting conditions of the imaging apparatus 100, it is confirmed whether the non-exposure time from the end of exposure of the first shooting frame to the start of exposure of the second shooting frame is longer than the switching time of the optical filter 201 (S200). Examples include interval recording or time-lapse recording. Here, the exposure means that the light incident from the lens is received by the imaging surface 132 of the imaging element 131 and acquired as image data. When the non-exposure time is longer than the switching time (YES in S200), when the optical filter switch 150 is pressed (S201), it is confirmed whether the image sensor 131 is being exposed (S202).

  When the exposure is in progress (YES in S202), the process waits until the exposure of the currently captured frame is completed (S203). As soon as the exposure of the frame is completed (S206), the optical filter 201 is switched (S207). If exposure is not in progress (NO in S202), it is confirmed whether the time until the start of exposure of the next frame is longer than the switching time of the optical filter 201 (S204). If it is long (YES in S204), the optical filter 201 is switched. If it is shorter (NO in S204), the process waits until the exposure of the next frame is completed (S205), and switches the optical filter 201 as soon as the exposure of the frame is completed (S206) (S207).

  After execution of switching of the optical filter 201, a flag indicating that the optical filter 201 has been changed is set in the frame after the end of switching of the optical filter 201 (S208). After setting the flag, it is confirmed whether or not to continue shooting (S120). If the photographing is continued (YES in S120), the setting of the imaging device 100 is confirmed again (S101). If shooting is not continued (NO in S120), shooting is terminated (S130). As described above, by performing switching of the optical filter 201 between exposure frames, it is possible to eliminate the reflection of the first arm portion 213.

  Further, by setting a flag in the frame after the end of the switching of the optical filter 201, it becomes easier to find the editing point after the photographing. If the non-exposure time from the end of exposure of the first shooting frame to the start of exposure of the second shooting frame is shorter than the switching time of the optical filter 201 in the setting conditions of the imaging apparatus 100 (NO in S200), 1 It is confirmed whether the exposure time of the frame is longer than the switching time of the optical filter 201 (S300). An example is slow shutter recording.

  When the exposure time of one frame is longer than the switching time of the optical filter 201 (YES in S300), when the optical filter switch 150 is pressed (S301), it is confirmed whether the image sensor 131 is being exposed (S302). . If exposure is not in progress (NO in S302), the process waits until exposure of the next frame starts (S303). As soon as exposure of the frame starts (S306), switching of the optical filter 201 is executed (S307). If exposure is in progress (YES in S302), it is confirmed whether the time until the end of exposure of the current frame is longer than the switching time of the optical filter 201 (S304).

  If it is long (YES in S304), the optical filter 201 is switched (S307). If it is shorter (NO in S304), it waits until the start of exposure of the next frame (S305), and switches the optical filter 201 as soon as exposure of the frame starts (S307). After execution of switching of the optical filter 201, a flag indicating that the optical filter 201 has been changed is set in the frame in which the optical filter 201 is being switched (S308). In this way, by starting and ending the switching of the optical filter 201 during the exposure of one frame, it is possible to eliminate a difference in density in one image due to a part of the reflection of the optical filter switching device 200. It is. In addition, by setting a flag on the frame during switching of the optical filter 201, it becomes easier to find an edited point after shooting.

  In the setting conditions of the imaging apparatus 100, when the time from the end of exposure of the first shooting frame to the start of exposure of the second shooting frame is shorter than the switching time of the optical filter 201 (NO in S200), one frame When the exposure time is shorter than the switching time of the optical filter 201 (NO in S300), when the optical filter switch 150 is pressed (S401), the optical filter is immediately switched (S402). After execution of switching of the optical filter 201, a flag indicating that the optical filter 201 has been changed is set in the frame after the start of switching of the optical filter 201 (S408).

  In the present embodiment, a neutral density filter is used as the optical filter, but an infrared photographing filter or a polarizing filter may be used. Further, although the rotating plate is used as the optical filter switching device, a slide type switching device or a liquid crystal dimming device may be used. Further, although the optical filter switching device in the imaging apparatus is used, an optical filter switching device in the lens may be used. In addition, although a switching instruction by a switch is used, a setting in a menu or a switching instruction from an external controller may be used. Further, although the switching timing of the optical filter in the recording state is dealt with, it may be in the camera standby state.

100 imaging device
120 Lens mount
130 Image sensor unit
131 Image sensor
132 Imaging surface
140 substrates
150 Optical filter selector switch
200 Optical filter switching device
201 Optical filter
202 First optical filter
203 Second optical filter
204 Third optical filter
210 Rotating plate
211 Center hole
212 Gear section
213 First arm
214 Second arm
215 Third arm
220 Motor unit
221 motor
222 Gear member
310 CPU
311 Switching instruction reception part
312 Switching timing decision section
313 Switching operation instruction section

Claims (5)

A plurality of optical filters;
An electric switching device capable of switching the optical filter to an arbitrary optical filter by electric driving means;
Operating means for instructing switching of the optical filter;
Storage means for storing in advance the switching time of the optical filter;
Control means for receiving the switching instruction and instructing to start the switching operation of the optical filter;
In an imaging apparatus having
The control means includes
Switching time stored by the storage means;
In successive shooting frames that the imaging device is shooting,
The exposure time of the first frame,
An image pickup apparatus, comprising: determining a timing of the switching operation of the optical filter from a non-exposure time between the first shooting frame and the second shooting frame. When the control means is instructed to switch the optical filter by the operation means,
2. The imaging according to claim 1, wherein when the non-exposure time is longer than the switching time, an instruction to start the switching operation of the optical filter is issued after the exposure of the first imaging frame is completed. apparatus. The imaging apparatus according to claim 1, wherein the control unit sets a flag for the second imaging frame. When the control means is instructed to switch the optical filter by the operation means,
2. The imaging apparatus according to claim 1, wherein when the exposure time is longer than the switching time, an instruction to start the switching operation of the optical filter is issued after the exposure of the first imaging frame is started. . The imaging apparatus according to claim 1, wherein the control unit sets a flag for the first imaging frame.