JP2005106970A - Exposure adjustment device for camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To miniaturize an exposure adjustment device applied to a digital camera or the like. <P>SOLUTION: The exposure adjustment device is provided with substrates 11 and 20 for demarcating apertures for exposure, a blade member 30 swingably provided on the substrate and moved from a position retreated from the apertures 11a and 20a to a position facing the apertures 11a and 20a, and an electromagnetic actuator 40 for driving the blade member 30. The apertures 20a and 11a are formed substantially rectangular on the basis of an imaging face of an imaging element. The blade member 30 is formed to make an outer contour 30c substantially rectangular so as to cover at least the apertures 11a and 20a, when they are at the positions facing the apertures 11a and 20a. Thereby, as compared with the conventional true circular shaped aperture, the outer contour of the blade can be made smaller, when the blade member is at a position retreated from the aperture, a stored region can be narrowed as compared with the conventional, and the width of the device can be made thin and compact. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an exposure adjustment device for a camera that opens / closes or stops an aperture for exposure, and more particularly, to an exposure adjustment device for a camera that is applied to a digital camera equipped with an image sensor such as a CCD.

As a conventional camera exposure adjustment device mounted on a digital camera or the like, there are a base plate and a back plate that define an opening for exposure, and a shutter that is swingably provided in a blade chamber defined by the base plate and the back plate. A so-called camera shutter device, camera diaphragm device, or the like having blades or diaphragm blades, an electromagnetic drive source for driving the shutter blades or diaphragm blades, or the like is known.
In this apparatus, the openings formed in the base plate and the back plate are determined on the basis of the image height derived from the light beam reaching the corners on the diagonal line on the imaging surface of the imaging device such as a CCD having a rectangular shape. It is formed in a perfect circle having a dimension of approximately a radius (a length of a diagonal is approximately a diameter).

  The shutter blade or the diaphragm blade has an outer contour that is substantially circular so as to have an area that completely covers the opening when the shutter blade or the diaphragm blade faces the opening by a closing operation or a diaphragm operation. The base plate and back plate are wide so that the shutter blade or the outer edge of the aperture blade is completely retracted from the opening when retracted from the opening by the diaphragm operation, that is, to accommodate the shutter blade or aperture blade in the retracted position. (For example, refer patent document 1, patent document 2, patent document 3, patent document 4).

JP 2001-117135 A JP 2002-139768 A JP 2003-5251 A JP 2003-131287 A

  By the way, in the above-described conventional camera exposure adjustment apparatus, the openings of the base plate and the back plate are formed in a perfect circle based on the diagonal line of the imaging element, so that the imaging of the imaging element having a rectangular shape is performed. The light beam can enter a region deviating from the surface to the outside. However, the light rays that enter the deviated region are essentially unnecessary regions because they do not contribute to photographing with the image sensor.

  On the other hand, the shutter blades or diaphragm blades are formed to have a larger outer contour so as to completely cover the perfect circular opening when located at the position facing the opening, and these blades move to the retracted position. At this time, since the base plate and the back plate are widely formed so that the outer edge portion can be completely retracted from the opening portion, it is difficult to reduce the size of the apparatus.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a blade member that adjusts exposure of shutter blades, diaphragm blades, and the like with respect to a substrate that defines an opening for exposure. In a configuration that can be swung freely, the shape of the opening is determined in consideration of the horizontal and vertical light rays incident on the image sensor, thereby reducing the width and size of the device. An object of the present invention is to provide a camera exposure adjustment apparatus suitable for a camera or the like.

An exposure adjustment apparatus for a camera according to the present invention includes a substrate that defines an opening for exposure, a blade member that is swingably provided on the substrate and moves between a position retracted from the opening and a position facing the opening, and a blade A drive source for driving the member, wherein the opening is formed in a substantially rectangular shape based on the imaging surface of the imaging element, and the blade member covers at least the opening when located at the position facing the opening. It is characterized in that it is formed to have a substantially rectangular outer contour.
According to this configuration, since the opening is formed in a substantially rectangular shape and the region of the blade member covering the opening is also formed in a substantially rectangular shape, the blade is compared with the conventional circular opening. The outer contour can be reduced. Therefore, the region accommodated when the blade member is driven by the driving source and retracted from the opening can also be narrowed compared to the conventional case, and the apparatus can be narrowed and miniaturized. .

In the above-described configuration, the substrate has two chambers that are spaced apart from each other in the optical axis direction so as to define a blade chamber that houses the blade member in a swingable manner and an opening for exposure. It is possible to adopt a configuration in which at least the opening of the plate located on the imaging element side is formed in a substantially rectangular shape based on the imaging surface of the imaging element.
According to this configuration, of the two plates defining the blade chamber, the substantially rectangular opening formed in the plate on the image sensor side of the subject light in the horizontal direction and the vertical direction entering the image sensor. The ray range is regulated. Therefore, of the two plates, the opening formed in the front plate may be rectangular like the opening on the image sensor side, and has a circular shape that is equal to or larger than the opening on the image sensor side. It may be an opening.

The said structure can employ | adopt the structure which is a shutter blade | wing which opens and closes an opening part.
According to this configuration, the shutter blade is driven by the drive source and moves between the open position retracted from the opening and the closed position facing the opening. That is, a camera light amount adjusting device (so-called camera shutter device) that is narrower and smaller than the conventional one having a perfect circular opening can be obtained.

The said structure can employ | adopt the structure which is a diaphragm blade | wing with a diaphragm opening which restrict | squeezes an opening part to a predetermined opening area.
According to this configuration, the diaphragm blade is driven by the driving source and moves between the non-diaphragm position retracted from the opening and the diaphragm position facing the opening. That is, a narrower and smaller camera light amount adjusting device (so-called camera diaphragm device) can be obtained as compared with a conventional device having a perfect circular opening.

The said structure can employ | adopt the structure which is an ND filter blade | wing containing the ND filter which reduces the light quantity which passes an opening part in a blade | wing member.
According to this configuration, the ND filter blade is driven by the drive source and moves between the non-adjustment position retracted from the opening and the adjustment position facing the opening. That is, the camera light amount adjusting device for a camera that is narrower and smaller than the conventional one having a perfect circular opening can be obtained.

In the above configuration, the ND filter blade may employ a configuration including a substantially rectangular opening larger than the opening and an ND filter joined so as to cover the opening.
According to this configuration, when the ND filter blade is at a position facing the opening, the amount of light passing through the opening is reduced to a predetermined level only by the action of the ND filter.

In the above configuration, the blade member includes a shutter blade that opens and closes the opening, a diaphragm blade having a diaphragm opening that restricts the opening to a predetermined opening area, and an ND filter blade that includes an ND filter that reduces the amount of light passing through the opening. A configuration including at least two blades can be employed.
According to this configuration, when the shutter blade and the diaphragm blade are provided, the shutter operation is performed together with the diaphragm operation, and when the shutter blade and the ND filter blade are provided, the shutter operation is performed together with the light amount reducing operation, and the diaphragm blade and the ND are performed. When the filter blades are provided, the light amount reduction operation is performed together with the diaphragm operation, and when the shutter blades and the diaphragm blades and the ND filter blades are provided, the diaphragm operation and the light amount reduction operation and the shutter operation are performed.
When at least two blades are arranged so as to be swingable on both sides of the opening, the area accommodated when the blades are retracted from the opening is made narrower on both sides than in the conventional case. The device can be made narrower and smaller.

  As described above, according to the camera light amount adjusting device of the present invention, the opening for exposure formed on the substrate is formed in a substantially rectangular shape based on the imaging surface of the imaging device, and is swingably supported on the substrate. The blade member is formed to have a substantially rectangular outer contour so as to cover at least the opening when the blade member is in a position facing the opening. Therefore, the area accommodated when the blade member is in a position retracted from the opening can also be narrowed compared to the conventional case, and the apparatus is narrowed and miniaturized. be able to. Therefore, a camera light amount adjustment device suitable for a small digital camera or the like can be obtained.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, exemplary embodiments of the invention will be described with reference to the accompanying drawings.
1 to 4 show an embodiment (camera shutter device) of a light amount adjusting device for a camera according to the present invention. FIG. 1 is a plan view of the device viewed from the image sensor side, and FIG. FIG. 3 is a plan view seen from the imaging element side showing a state in which the blade member is in a position retracted from the opening, and FIG. 4 is from the imaging element side showing a state in which the blade member faces the opening. FIG.

  As shown in FIGS. 1 and 2, this apparatus includes a base plate 10 and a back plate 20 as substrates whose outer contours are substantially rectangular, and shutter blades as blade members provided to be swingable with respect to the base plate 10. 30 and an electromagnetic actuator 40 as a drive source for driving the shutter blade 30.

  As shown in FIGS. 1 to 4, the base plate 10 supports the plate 11 that defines the opening 11a for exposure, the fan-shaped through-hole 12 through which the drive pin 41a, which will be described later, and the shutter blade 30 are swingably supported. It has a shaft 13. As shown in FIG. 1, the opening 11a of the plate 11 is formed in a substantially rectangular shape, and this outline is set so as to be substantially similar to the imaging surface of a CCD that is an imaging element of a digital camera. Yes.

As shown in FIGS. 1 to 4, the back plate 20 is connected to the base plate 10 at a predetermined interval in the optical axis direction L, and is an opening 20a for exposure formed coaxially with the opening 11a. And a circular hole 20c through which the drive pin 41a passes and a circular hole 20c through which the support shaft 13 passes.
As shown in FIG. 1, the opening 20a is formed in a substantially rectangular shape, and this outline is set so as to be substantially similar to the imaging surface of the CCD as described above. The opening 20a is substantially the same as the opening 11a or is formed slightly larger than the opening 11a.
The back plate 20 and the plate 11 define two blade chambers R that accommodate the shutter blades 30 in a swingable manner and two openings 20a and 11a for exposure that are spaced apart in the optical axis direction L. A plate is constructed.

As shown in FIGS. 2 to 4, the shutter blade 30 has an area covering the circular hole 30a through which the support shaft 13 passes, the long hole 30b through which the drive pin 41a passes, and the openings 11a and 20a by a thin metal plate or the like. It is formed so as to have a shielding portion 30c having a substantially rectangular outer contour.
As shown in FIG. 4, the shielding portion 30c can completely shield the openings 11a and 20a when the shutter blade 30 is in the closed position facing the openings 11a and 20a, and can be opened from the openings 11a and 20a. When the movement toward the closing position is started, when a closing operation is started, a region that does not open again in the middle of the operation does not occur and a minimum outer contour is formed.

The electromagnetic actuator 40 includes a columnar rotor 41 magnetized with different polarities (N pole and S pole), a frame member 42 that rotatably supports the rotor 41, and an exciting coil wound around the frame member 42. 43, a cylindrical yoke 44 fitted into the frame member 42 on the same axis as the rotor 41, an iron pin 45 inserted into the frame member 42, and the like.
The rotor 41 is integrally formed with a drive pin 41a for outputting a rotational driving force to the outside at a position deviated from the rotation shaft. The electromagnetic actuator 40 is fixed to the main plate 10 via a frame member 42 with screws or the like.

  Regarding the operation of this apparatus, when the shutter operation is performed, the electromagnetic actuator 40 is energized from the state where the shutter blade 30 is in the retracted position (open position) as shown in FIG. 3, and the rotor 41 rotates counterclockwise. Then, as shown in FIG. 4, the shutter blade 30 rotates counterclockwise, and the shielding portion 30c stops at a position where the openings 11a and 20a are completely closed. On the other hand, when the electromagnetic actuator 40 is reversely energized, the shutter blade 30 returns to the original retracted position (open position).

  According to this apparatus, the openings 11a and 20a are formed in a substantially rectangular shape, and the shutter blade shielding portion 30c is also formed in a substantially rectangular shape. Therefore, as shown in FIG. Compared with the case where ', 20a' is formed in a perfect circle and the shutter blade (shielding portion) 30 'is also formed in a circle, the outer contour of the blade can be reduced. Therefore, the area of the substrate (base plate 10, back plate 20) accommodated when the shutter blade 30 is in the retracted position is also sized compared to the conventional substrate (base plate 10 ', back plate 20'). The width can be narrowed by W. Therefore, the apparatus can be narrowed and downsized.

  6 to 8 show another embodiment of the light amount adjusting device for a camera according to the present invention. The same reference numerals are given to the same components as those of the above-described embodiment, and the description thereof will be omitted. 6 is a plan view of the apparatus as viewed from the image sensor side, FIG. 7 is a plan view of the apparatus as viewed from the image sensor side showing a state in which the blade member is retracted from the opening, and FIG. It is the top view seen from the image sensor side which shows the state which exists in the position which faces.

In this apparatus, as shown in FIGS. 6 to 8, ND filter blades 130 as blade members are provided to be swingable with respect to the base plate 10.
As shown in FIGS. 7 and 8, the ND filter blade 130 is formed by a blade 131 formed of a thin metal plate or the like and a film-like ND filter 132 bonded to the blade 131.

The blades 131 are formed in a circular hole 131a through which the support shaft 13 is passed, a long hole 131b through which the drive pin 41a is passed, a cover part 131c having an area that covers the openings 11a and 20a, and a cover part 131c that forms a substantially rectangular outer contour. It is formed so as to have a substantially rectangular opening 131d and the like.
As shown in FIG. 8, the cover 131c can completely cover the openings 11a and 20a when the ND filter blade 130 is in the closed position facing the openings 11a and 20a, and retracts from the openings 11a and 20a. When moving toward the facing position from the position, the cover is formed so as to form a minimum outer contour with a shape in which an opening area does not occur again in the middle of the operation when covering is started. The opening 131d is formed slightly larger than the openings 11a and 20a.

  Regarding the operation of this apparatus, when the light quantity reduction operation is performed, when the electromagnetic actuator 40 is energized and the rotor 41 rotates clockwise from the state where the ND filter blade 130 is in the retracted position as shown in FIG. As shown in FIG. 8, the ND filter blade 130 rotates clockwise and stops at a position where the cover 131c completely covers the openings 11a and 20a. Accordingly, the openings 11a and 20a are covered with the ND filter 132, and the amount of light passing therethrough is reduced to a predetermined level. On the other hand, when the electromagnetic actuator 40 is reversely energized, the ND filter blade 130 returns to the original retracted position.

  According to this apparatus, the openings 11a and 20a are formed in a substantially rectangular shape, and the cover portion 131c of the ND filter blade is also formed in a substantially rectangular shape. Therefore, as shown in FIG. Compared to the case where 11a ′ and 20a ′ are formed in a perfect circle and the ND filter blade (cover and opening 131d ′) 130 ′ is also formed in a circle, the outer contour of the blade can be made smaller. Therefore, the area of the substrate (base plate 10, back plate 20) accommodated when the ND filter blade 130 is in the retracted position is also compared to the substrate (base plate 10 ', back plate 20') formed as in the past. The dimension W can be narrowed, and therefore the apparatus can be narrowed and miniaturized.

  10 to 14 show still another embodiment of the light amount adjusting device for a camera according to the present invention. The same components as those of the above-described embodiment are denoted by the same reference numerals and the description thereof is omitted. . 10 is a plan view of the apparatus viewed from the image sensor side, FIG. 11 is a cross-sectional view of the apparatus, and FIG. 12 is a plan view of the apparatus viewed from the image sensor side showing a state where two blade members are retracted from the opening. FIG. 13 is a plan view seen from the image sensor side showing a state where one blade member is facing the opening, and FIG. 14 is an image sensor side showing a state where two blade members are facing the opening. It is the top view seen from.

  As shown in FIGS. 10 and 11, this apparatus includes a ground plate 110 and a back plate 120 as substrates whose outer contours are substantially rectangular, and shutter blades as blade members that are swingable with respect to the ground plate 110. 30 and ND filter blades 130, and two electromagnetic actuators 40 as drive sources for driving the shutter blades 30 and the ND filter blades 130, respectively.

  As shown in FIGS. 10 to 14, the base plate 110 includes a plate 111 that defines an opening 111a for exposure, two fan-shaped through holes 112 through which two drive pins 41a pass, a shutter blade 30 and an ND filter blade 130. It has two support shafts 113 that are swingably supported. As shown in FIG. 10, the opening 111a of the plate 111 is formed in a substantially rectangular shape, and this outline is set so as to have a substantially similar shape to the imaging surface of the CCD as described above.

As shown in FIGS. 10 to 14, the back plate 120 is connected to the base plate 110 at a predetermined interval in the optical axis direction L, and is an opening 120a for exposure formed coaxially with the opening 111a. It has two arc-shaped long holes 120b through which the two drive pins 41a pass, and two circular holes 120c through which the two support shafts 113 pass. As shown in FIG. 10, the opening 120a is formed in a substantially rectangular shape, and this outline is set so as to be substantially similar to the imaging surface of the CCD as described above. The opening 120a is substantially the same as the opening 111a or is formed slightly larger than the opening 111a.
The back plate 120 and the plate 111 are separated from each other in the optical axis direction L so as to define a blade chamber R for accommodating the shutter blade 30 and the ND filter blade 130 in a swingable manner and openings 120a and 111a for exposure. Two arranged plates are constructed.

  Regarding the operation of this device, when the light quantity reduction operation is performed, when one of the electromagnetic actuators 40 is energized and the rotor 41 rotates clockwise from the state where the ND filter blades 130 are in the retracted position as shown in FIG. As shown in FIG. 13, the ND filter blade 130 rotates clockwise and stops at a position where the cover 131c completely covers the openings 111a and 120a. Accordingly, the openings 111a and 120a are covered with the ND filter 132, and the amount of light passing therethrough is reduced to a predetermined level.

  Subsequently, when performing the shutter operation, when the other electromagnetic actuator 40 is energized and the rotor 41 rotates counterclockwise from the state where the shutter blade 30 is in the retracted position (open position) as shown in FIG. As shown in FIG. 14, the shutter blade 30 rotates counterclockwise, and the shielding portion 30c stops at a position where the opening 131d and the openings 111a and 120a are completely closed. On the other hand, when both the electromagnetic actuators 40 are reversely energized, the shutter blade 30 and the ND filter blade 130 return to the original retracted position (open position).

According to this apparatus, the openings 111a and 120a are formed in a substantially rectangular shape, and the shutter blade shielding portion 30c and the ND filter blade covering portion 131c are also formed in a substantially rectangular shape, as shown in FIG. The openings 111 a ′ and 120 a ′ are formed in a perfect circle as in the prior art, the shutter blade (shielding portion) 30 ′ is also formed in a circle, and the ND filter blade (cover portion 131 c ′ and opening 131 d ′) 130 ′. In addition, the outer contours of the shutter blades 30 and the ND filter blades 130 can be reduced as compared with the case of forming the circular shape.
Therefore, the area of the substrate (base plate 110, back plate 120) accommodated when the shutter blade 30 and the ND filter blade 130 are in the retracted position is the same as that of the conventional substrate (base plate 110 ', back plate 120'). ) Can be narrowed by a dimension (W + W) compared to the above), and therefore the apparatus can be narrowed and miniaturized.

In the above embodiment, the openings 20a, 120a formed in the back plates 20, 120 and the openings 11a, 111a formed in the plates 11, 111 are both rectangular, but the present invention is not limited to this. Since the photographing light focused by the opening on the side is obliquely directed to the opening on the image sensor side that is separated from the blade chamber in the optical axis direction, the openings 20a and 120a of the back plates 20 and 120 on the subject side May be formed in a slightly larger circle than the openings 11a, 111a of the plates 11, 111 on the image sensor side.
Similarly, even when the openings 20a, 120a and the openings 11a, 111a are both rectangular, the openings 20a, 120a may be formed slightly larger.

  In the above-described embodiment, the shutter blade 30 and the ND filter blade 130 are shown as the blade members. However, the present invention is not limited to this, and a diaphragm opening that restricts the openings 11a, 111a, 20a, and 120a to a predetermined opening area. In addition, the configuration including the shutter blade 30 and the ND filter blade 130 is shown as an apparatus including a plurality of blade members, but the present invention is not limited to this. The present invention may be employed in a configuration that includes 30 and a diaphragm blade, a diaphragm blade and an ND filter blade 130, and a shutter blade 30 and a diaphragm blade and an ND filter blade 130, respectively.

  As described above, the camera exposure adjustment apparatus of the present invention can be a digital camera (digital still camera, digital video camera), mobile phone, portable personal computer, PDA, etc., as long as it has an image sensor such as a CCD. It can be used for a mobile camera mounted on a portable information terminal.

It is a top view which shows one Embodiment of the exposure adjustment apparatus for cameras which concerns on this invention. It is sectional drawing of the apparatus shown in FIG. FIG. 2 is a plan view showing a state in which the shutter blade is in a position retracted from an opening in the apparatus shown in FIG. 1. In the apparatus shown in FIG. 1, it is a top view which shows the state which has a shutter blade | wing in the position which faces an opening part. FIG. 2 is a plan view for explaining the effect of the present invention in the apparatus shown in FIG. 1. It is a top view which shows other embodiment of the exposure adjustment apparatus for cameras which concerns on this invention. FIG. 7 is a plan view showing a state where the ND filter blade is in a position retracted from the opening in the apparatus shown in FIG. 6. FIG. 7 is a plan view showing a state where the ND filter blade is in a position facing the opening in the apparatus shown in FIG. 6. FIG. 7 is a plan view for explaining the effect of the present invention in the apparatus shown in FIG. 6. It is a top view which shows other embodiment of the exposure adjustment apparatus for cameras which concerns on this invention. It is sectional drawing of the apparatus shown in FIG. FIG. 11 is a plan view illustrating a state in which the shutter blade and the ND filter blade are in a position retracted from the opening in the apparatus illustrated in FIG. 10. In the apparatus shown in FIG. 10, it is a top view which shows the state which the ND filter blade | wing moved to the position which faces an opening part. In the apparatus shown in FIG. 10, it is a top view which shows the state which exists in the position which a shutter blade | wing and ND filter blade | wing face an opening part. In the apparatus shown in FIG. 10, it is a top view for demonstrating the effect of this invention.

Explanation of symbols

10,110 Ground plane (substrate)
11, 111 Plates 11a, 111a Openings 20, 120 Back plate (plate)
20a, 120a Opening 30 Shutter blade (blade member)
30c Shielding part 40 Electromagnetic actuator 41 Rotor 41a Drive pin 42 Frame member 43 Coil 44 Yoke 45 Iron pin 130 ND filter blade (blade member)
131 Blade 132 ND filter 131c Cover 131d Opening L Optical axis direction R Blade chamber

Claims (7)

A substrate that defines an opening for exposure, a blade member that is swingably provided on the substrate and moves between a position retracted from the opening and a position facing the opening, and a drive source that drives the blade member And comprising
The opening is formed in a substantially rectangular shape based on the imaging surface of the imaging element,
The blade member is formed to have a substantially rectangular outer contour so as to cover at least the opening when located at the position facing the opening.
An exposure adjustment apparatus for a camera. The substrate has two plates that are arranged apart from each other in the optical axis direction so as to define a blade chamber that slidably accommodates the blade member and an opening for exposure.
The opening of the plate located at least on the image sensor side of the two plates is formed in a substantially rectangular shape based on the image sensing surface of the image sensor,
2. An exposure adjusting apparatus for a camera according to claim 1, wherein: The blade member is a shutter blade that opens and closes the opening.
The camera exposure adjustment apparatus according to claim 1 or 2, wherein The blade member is a diaphragm blade having a diaphragm opening that restricts the opening to a predetermined opening area.
The camera exposure adjustment apparatus according to claim 1 or 2, wherein The blade member is an ND filter blade including an ND filter that reduces the amount of light passing through the opening.
The camera exposure adjustment apparatus according to claim 1 or 2, wherein The ND filter blade includes a substantially rectangular opening larger than the opening, and an ND filter joined to cover the opening.
6. An exposure adjusting apparatus for a camera according to claim 5, wherein The blade member includes a shutter blade that opens and closes the opening, a diaphragm blade having a diaphragm opening that restricts the opening to a predetermined opening area, and an ND filter blade that includes an ND filter that reduces the amount of light passing through the opening. Including at least two vanes,
The camera exposure adjusting apparatus according to claim 1, wherein the camera exposure adjusting apparatus is a camera exposure adjusting apparatus.

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