JP2009025454A - Optical equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form an AF image for obtaining excellent focus detection performance by a phase difference detection system and to improve the detecting accuracy of the AF image. <P>SOLUTION: Optical equipment has: a deflecting optical means 40 deflecting at least one of first luminous flux 1 and second luminous flux 2 respectively passing through a first area 41a and a second area 41b in the exit pupil of an optical system 10 and reaching a photoelectric conversion element 6 in a different direction from the separating direction of the first and second areas relative to the other luminous flux; and a focus detection means detecting the focus state of the optical system based on a signal obtained from the photoelectric conversion element in accordance with a first image 7a and a second image 7b formed with the first and second luminous fluxes. The focus detection means changes the tilt angle θ1 of a photoelectric conversion area in which signals in accordance with the first and second images are respectively fetched out of the photoelectric conversion element based on information on the optical system. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an optical apparatus that forms a plurality of images on a photoelectric conversion element in order to perform focus detection by a so-called phase difference detection method.

  In a single-lens reflex camera, AF based on a TTL (Through the Taking Lens) phase difference detection method is generally employed. In the phase difference detection method, the light beam from the subject captured through the imaging lens is reflected by the movable mirror and guided onto a surface equivalent to the light receiving surface of the film or the imaging device (primary imaging surface). The light beam guided to the equivalent surface is separated into two (pupil separation or pupil division) by a secondary imaging optical system including a separator lens and guided onto a pair of AF line sensors. Then, by detecting a shift (phase difference) between the two images on the pair of line sensors, a shift amount from the in-focus position of the focus lens in the imaging lens is obtained.

  By the way, the digital camera has an image sensor as a photoelectric conversion element that photoelectrically converts a subject image. If a part of this image sensor is used as the AF sensor area, it is not necessary to provide a secondary imaging optical system separate from the AF dedicated line sensor and the imaging lens.

  For this reason, a focus detection system has been proposed in which a part of the image sensor is used as an AF sensor area, and two light beams separated by a split image prism provided in the image pickup optical system are guided to the area. Patent Document 1).

In addition, a configuration has been proposed in which TTL phase difference AF is realized by disposing a holographic optical element on the object side from the primary imaging plane (see Patent Document 2).
JP-A-2004-46132 (paragraphs 0015 to 0041, FIGS. 4 to 7 etc.) JP-A-4-147207 (page 3, lower left column, line 5 to page 4, upper right column, line 7, line 3, etc.)

  However, unlike the TTL phase difference detection method, the method using the split image prism proposed in Patent Document 1 requires image continuity on the boundary line of the spirit image prism. For example, if the shape of the image on the boundary line of the split image prism is not a straight line, even if it is in focus, it is determined that the image is out of focus. Focus detection performance equivalent to the detection method cannot be obtained.

  Further, the method using the holographic optical element proposed in Patent Document 2 is in principle the same as the TTL phase difference detection method. However, a holographic optical element having a large chromatic dispersion is used when forming two images (AF images) in the pupil separation direction, which is important in determining the focus state. For this reason, the difference in incident angle between phase difference images, which is important for obtaining focus detection accuracy, deviates greatly depending on the wavelength, which is not practical for focus detection.

  The present invention provides an optical apparatus capable of forming an AF image for obtaining good focus detection performance by a phase difference detection method and improving the detection accuracy of the AF image.

  An optical apparatus according to one aspect of the present invention includes at least one of a first light flux and a second light flux that respectively pass through a first region and a second region in an exit pupil of an optical system and reach a photoelectric conversion element. Deflecting optical means for deflecting the light beam in the direction different from the separation direction of the first and second regions with respect to the other light beam, and the first and second images formed by the first and second light beams. And a focus detection means for detecting the focus state of the optical system based on a signal obtained from the photoelectric conversion element in accordance with the image. The focus detection unit is characterized in that the inclination angle of the photoelectric conversion region that takes in signals corresponding to the first and second images of the photoelectric conversion element is changed based on information about the optical system.

  According to the present invention, at least one of the first and second light beams is deflected in a direction different from the pupil separation direction by so-called pupil separation, thereby forming an AF image with less aberration in different regions on the photoelectric conversion element. can do. In addition, even when the AF image is formed obliquely on the photoelectric conversion element by changing the inclination angle of the region in which the signal corresponding to the AF image in the photoelectric conversion element is captured based on the information about the optical system, it is high. Focus detection performance can be obtained.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  First, the optical apparatus previously proposed by the present applicant (see JP-A-2006-71950) will be briefly described with reference to FIGS. 9A to 11C. This optical apparatus is suitable for focus detection by the TTL phase difference detection method, and can reduce a shift due to a wavelength of a substantial difference in incident angle between AF images.

  FIG. 9A shows an imaging state for acquiring a recording image of a subject in the optical device, and FIG. 9B shows a focus detection state for performing autofocus (AF) in the optical device. In the description here and the embodiments described later, it is assumed that the optical device is a lens-integrated digital camera that is an imaging device. However, the optical device may be a lens device that is detachably attached to the imaging device.

  In these figures, reference numeral 110 denotes an imaging optical system, which is a zoom optical system having a first lens unit I, a second lens unit II, and a third lens unit III in order from the subject side (left side in the figure).

  Reference numeral 140 denotes a light deflection unit as deflection optical means, which is inserted into and retracted from an internal space on the optical path of the imaging optical system 110, specifically, a space between the first lens unit I and the second lens unit II. Is possible. This space is the position of the exit pupil of the imaging optical system 110 or a position close thereto.

  Reference numeral 101 denotes an incident light beam of the imaging optical system 110 (only a light beam passing through the center of the pupil of the imaging optical system 110 is shown in the figure).

  FIG. 10 shows a state in which the light deflection unit 140 is viewed from the front side (subject side) of the imaging optical system 110. In the light deflection unit 140, two separated pupils (first region and second region) 141a and 141b are formed by the light shielding mask 142. Each separation pupil is provided with a deflection optical element that deflects the incident light beam and a light limiting element that restricts the incident angle of the light beam on the deflection optical element.

  Each of the deflecting optical elements provided in the separation pupils 141a and 141b has a function of deflecting the light beam in the direction of the arrow in the drawing, that is, in the opposite directions. This deflection direction is a direction different from the pupil separation direction, and specifically, a direction orthogonal to the pupil separation direction.

  As a result, as shown in FIG. 9B, a light beam (first light beam) 101a that passes through the separation pupil 141a and reaches the image sensor 106 is an AF image (first image) on the upper side of the image sensor 106 as a photoelectric conversion element. : Hereinafter also referred to as A image). A light beam (second light beam) 101b that passes through the separation pupil 141b and reaches the image sensor 106 forms an AF image (second image: hereinafter also referred to as a B image) on the lower side of the image sensor 6.

  Note that “orthogonal”, “parallel”, and “match (identical)” used in this specification are not only strictly orthogonal, parallel, and coincide, but are also orthogonal, parallel, and coincidence in terms of optical or focus detection performance. It means to include even when it can be considered.

  Next, an operation for detecting the A image and the B image by the image sensor 106 will be described. FIG. 11A shows AF image detection areas (photoelectric conversion areas for capturing image signals) 161a and 161b for photoelectrically converting the A and B images on the image sensor 106. FIG. 11B shows the AF image detection areas 161a and 161b in an enlarged manner.

  In each AF image detection area (each photoelectric conversion area), as shown in FIG. 11C, a pixel block (pixel column) 161a1, including a plurality of pixels arranged in two columns in the vertical direction (the short side direction of the image sensor 106). A plurality of 161b1 are arranged in the left-right direction (long-side direction of the image sensor 106). The vertical direction is a direction orthogonal to the pupil separation direction. The left-right direction is the pupil separation direction (direction parallel to). FIG. 11C also shows the arrangement of color filters in one pixel block. R represents red, G represents green, and B represents blue.

  When the pixel blocks 161a1 and 161b1 shown in FIG. 11C are added so as to generate single image information as unit pixels in AF image detection, the AF image information in the vertical direction is averaged including color information. However, since the unit pixel in the left-right direction is an area for two pixels corresponding to the resolution of the original image sensor 106, the resolution sufficient for detecting the shift amount of the AF image is suppressed while suppressing the influence of chromatic dispersion. Can be secured.

  By performing autocorrelation processing on the deviation amount of the light intensity distribution of the paired AF images (A image and B image) obtained as described above, the focus deviation amount (defocus amount) of the imaging optical system 110 is obtained. Can be detected.

  FIG. 12 shows an example of AF images (A image, B image) 107a and 107b formed on the AF image detection areas 161a and 161b by the light beams that have passed through the separation pupils 141a and 141b in the focus detection state shown in FIG. 9B. Indicates. Here, an AF image when the image sensor 106 is viewed from the side facing the light receiving surface (front side), which is an inverted image, is inverted upside down (rotated 180 degrees around the optical axis). It shows an image.

  In this configuration, in the front pin state, the lower AF image (A image) 107a is shifted to the left, and the upper AF image (B image) 107b is shifted to the right. Further, in the rear pin state, the shift directions of the AF images 107a and 107b are reversed.

  If the AF image formed by the light beam that has passed through the separation pupils 141a and 141b is formed by a telecentric optical system on the image side of the separation pupil (light deflection unit 140), the focus is shifted. The A and B images move in the horizontal direction. However, if it is not formed by a telecentric optical system on the image side, the A image and the B image move in an oblique direction when the image is out of focus.

  13A to 13F are diagrams illustrating the inclination of the subject image and the shift direction of the AF image.

  FIG. 13A shows a state of the A image and the B image in the front pin state. FIG. 13C shows a state of the A image and the B image in the focused state. FIG. 13E shows the state of the A and B images in the rear pin state. As subject images, assuming images of subjects at the same distance, tilted to the right, images a1 and b1, vertical images a2 and b2, and images a3 and b3 tilted to the left, A images (a1 to a3), respectively. ) And B images (b1 to b3) according to the focus shift.

  FIG. 13B shows the states of the A image (a1 to a3) and the B image (b1 to b3) in the AF image detection areas 161a and 161b in the front pin state. FIG. 13D shows the states of the A image (a1 to a3) and the B image (b1 to b3) in the AF image detection areas 161a and 161b in the focused state. Further, FIG. 13F shows the states of the A image (a1 to a3) and the B image (b1 to b3) in the AF image detection areas 161a and 161b in the rear pin state.

  As can be seen from these figures, when the subject images are the vertical images a2 and b2, the lateral image shift amount (phase difference) S on the image sensor 106 due to the focus shift and the AF image detection areas 161a and 161b. The image shift amount S in FIG. However, when the subject image is an oblique image a1, b1, a3, b3, the image in the AF image detection areas 161a, 161b with respect to the lateral image shift amount S on the image sensor 106 due to focus shift. The shift amounts (S ′, S ″) are different. For example, in the images a1 and b1 tilted diagonally to the right, the AF image detection areas 161a and 161b are more than the horizontal image shift amount S on the image sensor 106 due to the focus shift. In the images a3 and b3 tilted obliquely to the right, the AF image detection areas 161a and 161b are smaller than the lateral image shift amount S on the image sensor 106 due to the focus shift. The image shift amount S ″ in the image increases.

  In other words, even in the same out-of-focus state, the amount of image shift detected in the AF image detection areas 161a and 161b differs depending on the tilt and direction of the AF image, and as a result, a focus detection error may occur. In the embodiment described below, a method for suppressing a focus detection error that occurs when the subject image (AF image) shown in FIGS. 13A to 13F is an oblique image will be described.

  1A and 1B show a configuration in a focus detection state at the wide end of an optical apparatus that is an embodiment of the present invention. FIG. 1A shows a side cross section of the optical device, and FIG. 1B shows a horizontal cross section of the optical device.

  Reference numeral 10 denotes an imaging optical system, which is a zoom optical system having a first lens unit I, a second lens unit II, and a third lens unit III in order from the subject side (left side in the figure). The focal length can be changed between the wide end and the tele end by moving each lens unit as indicated by an arrow shown on the lower side of the figure to change the distance between the lens surfaces.

  Reference numeral 60 denotes an optical low-pass filter (LPF) having a function of alleviating the phenomenon of false color and moire mainly generated in a digital camera. Reference numeral 6 denotes an imaging element as a photoelectric conversion element that performs photoelectric conversion on a subject image formed by the imaging optical system 10. An image signal is generated based on the output from the image sensor 6, and the image signal is recorded on a recording medium such as a semiconductor memory (not shown), an optical disk, or a magnetic tape.

  Reference numeral 40 denotes an optical deflection unit that can be inserted into and retracted from an internal space on the optical path of the imaging optical system 10, specifically, a space between the first lens unit I and the second lens unit II. This space is the position of the exit pupil of the imaging optical system 10 or a position close thereto. The light deflection unit 40 moves in the optical axis direction together with the second lens unit II during zooming (magnification).

  Reference numeral 30 denotes a focusing unit that calculates (detects) a focus state (defocus amount) of the imaging optical system 10 and a focus control unit that calculates a focus lens drive amount for focusing mainly in autofocus (AF). It is a functioning controller.

  FIG. 2 shows the light deflection unit 40 as viewed from the front side (subject side) of the imaging optical system 10. In the light deflection unit 40, two separated pupils (first and second regions) 41a and 41b are formed by a light shielding mask. Each separation pupil is provided with a deflection optical element that deflects the incident light beam and a light limiting element that restricts the incident angle of the light beam on the deflection optical element.

  As can be seen from FIG. 1B, in the light deflection unit 40, two separation pupils 41a and 41b are formed in the horizontal direction. Further, as can be seen from FIGS. 1A and 2, the deflecting optical elements 43a and 43b each have a function of deflecting the light beam in the direction of the arrow in the drawing, that is, in the opposite directions. Specifically, the deflection optical element 43a deflects the incident light beam (first light beam) 1a upward as indicated by an arrow in the figure, and the deflection optical element 43b performs the incident light beam (second light beam). 1b is deflected downward as indicated by an arrow in the figure. The vertical direction that is the deflection direction is a direction different from the pupil separation direction, and specifically, is a direction orthogonal to the pupil separation direction.

  As the deflection optical element, a so-called blazed prism sheet (linear blazed prism sheet) in which sawtooth or triangular prism shapes are continuously arranged in the direction indicated by the arrow in FIG. 2 can be used. The deflection angle of the light beam is determined according to the above conditions. In such a deflection optical element, the light beam is deflected in the blaze direction indicated by the arrow in the drawing. Therefore, by reversing the blaze direction with the two deflecting optical elements provided in the separation pupils 41a and 41b, the first light beam and the second light beam incident thereon can be deflected in opposite directions. it can.

  The pitch of the sawtooth or triangular prism shape is preferably 0.5 mm, for example, so that the influence of diffraction on the first and second light beams is small.

  Further, as the deflecting optical element, a linear blazed diffraction grating capable of deflecting an incident light beam using a light diffraction phenomenon may be used. In this case, the deflection angle is determined by the diffraction condition formula, and the dispersion direction is opposite to the refraction condition.

  Reference numeral 1 denotes an incident light beam of the imaging optical system 10 (only a light beam passing through the pupil center of the imaging optical system 10 is shown in the figure).

  With such a configuration, as shown in FIG. 1A, a light beam (first light beam) 1a that passes through the separation pupil 41a and reaches the image sensor 6 is placed on the upper side of the image sensor 6 with an AF image (first image: (Hereinafter also referred to as A image). A light beam (second light beam) 1b that passes through the separation pupil 41b and reaches the image sensor 6 forms an AF image (second image: hereinafter also referred to as a B image) on the lower side of the image sensor 6. .

  On the other hand, as shown in FIG. 1B, the light beams 1 a and 1 b that have passed through the separation pupils 41 a and 41 b form an A image and a B image near the center in the horizontal direction of the image sensor 6 in the horizontal section.

  The light beams 1a and 1b shown in FIG. 1B form an angle in the horizontal direction with respect to the normal line of the light receiving surface when incident on the light receiving surface of the image sensor 6. For this reason, an image shift in the horizontal direction (shift between the A image and the B image, that is, a phase difference) occurs according to the focus shift. Further, as shown in FIG. 1A, when the light beams 1a and 1b are incident on the light receiving surface of the image pickup device 6, an angle is formed in the vertical direction with respect to the normal line of the light receiving surface, so Also, image displacement occurs.

  Next, in this embodiment, an operation for detecting the A image and the B image by the image sensor 6 will be described.

  FIG. 3A shows an AF image detection area (photoelectric conversion area for capturing an image signal) on the image sensor 6 at the wide end. The AF image detection areas 61a and 61b photoelectrically convert the A and B images, respectively, and output signals (image signals) corresponding to the A and B images. FIG. 3B shows the AF image detection areas 61a and 61b in an enlarged manner.

  In each AF image detection area (each photoelectric conversion region), as shown in FIG. 3C, pixel blocks (pixel columns) 61a1, including a plurality of pixels arranged in two columns in the vertical direction (the short side direction of the image sensor 6). A plurality of 61b1 are arranged in the left-right direction (long-side direction of the image sensor 6). The vertical direction is a direction orthogonal to the pupil separation direction. The left-right direction is the pupil separation direction (a direction parallel to the pupil separation direction).

  FIG. 3C also shows the arrangement of color filters in one pixel block. R represents red, G represents green, and B represents blue.

  Here, in this embodiment, as shown in FIG. 3A, the AF image detection areas 61a and 61b have an inclination angle θ1 with respect to the horizontal direction. In order to have this inclination angle θ1, in this embodiment, at least a part of the plurality of pixel blocks (pixel columns) included in each AF image detection area is set to the pupil separation direction with respect to the other pixel blocks. Are shifted in different directions in the vertical direction (up and down direction).

  Actually, the vertical step (shift amount) of the pixel blocks 61 a 1 and 61 b 1 needs to be an integral multiple of the unit pixel of the image sensor 6. Therefore, a plurality of pixel blocks arranged in the horizontal direction are bundled to form a plurality of pixel block groups, and each pixel block group is shifted in the vertical direction.

  The tilt angle θ1 is made to coincide with the angle of the shift direction (displacement direction) of the AF image (A image, B image) accompanying the focus shift (change in focus state). For this reason, the controller 30 obtains the angle of the shift direction of the AF image based on the information related to the imaging optical system 10, and determines the tilt angle θ1 so as to coincide with the obtained angle of the shift direction. Then, the shift amount in the vertical direction for each pixel block group is set so that the tilt angle θ1 is obtained. The information regarding the imaging optical system 10 includes the configuration of the lens unit of the imaging optical system 10, the position of each lens unit, the focal length, and the like.

  When the pixel blocks 61a1 and 61b1 shown in FIG. 3C are added so as to generate single image information (image signal) as unit pixels in AF image detection, the AF image information in the vertical direction includes color information. Averaged. However, since the unit pixel in the left-right direction is an area for two pixels corresponding to the resolution of the original image sensor 6, a sufficient resolution for detecting the shift amount of the AF image can be obtained while suppressing the influence of chromatic dispersion. Can be secured.

  By performing autocorrelation processing by the controller 30 on the deviation amount of the light intensity distribution of the paired AF images (A image and B image) obtained as described above, the focus deviation amount of the imaging optical system 10 ( (Defocus amount) can be detected.

  4A to 4F show the inclination of the subject image and the shift direction of the AF image in the present embodiment.

  FIG. 4A shows the state of the A and B images in the front pin state. FIG. 4C shows a state of the A image and the B image in the focused state. FIG. 4E shows the state of the A and B images in the rear pin state. As subject images, assuming images of subjects at the same distance, tilted to the right, images a1 and b1, vertical images a2 and b2, and images a3 and b3 tilted to the left, A images (a1 to a3), respectively. ) And B images (b1 to b3) according to the focus shift.

  FIG. 4B shows a state of A images (a1 to a3) and B images (b1 to b3) in the AF image detection areas 61a and 61b in the front pin state. FIG. 4D shows the states of the A image (a1 to a3) and the B image (b1 to b3) in the AF image detection areas 61a and 61b in the focused state. Furthermore, FIG. 4F shows a state of A images (a1 to a3) and B images (b1 to b3) in the AF image detection areas 61a and 61b in the rear pin state.

  As can be seen from these figures, in any case where the subject image is a1 to a3 or b1 to b3, the lateral image shift amount (phase difference) S on the image sensor 6 (photoelectric conversion element) due to the focus shift. And the image shift amount S in the AF image detection areas 61a and 61b coincide with each other.

  Thus, the focus detection accuracy can be improved by matching the inclination angle θ1 of the AF image detection areas 61a and 61b with the angle in the image shift direction accompanying the focus shift.

  5A and 5B show how multipoint focus detection is performed at the wide end. FIG. 5A shows a focus detection area (small rectangular frame) in multipoint focus detection, and FIG. 5B shows AF images (A and B images) 7a and 7b formed by light beams that have passed through the separation pupils 41a and 41b. An example is shown. Here, an AF image when the image sensor 6 is viewed from the side facing the light receiving surface (front side), which is an inverted image, is inverted vertically (rotated 180 degrees around the optical axis). It shows an image.

  A case will be described in which a peripheral focus detection area (focus detection area indicated by “select”) out of the center of the screen is selected by the photographer from among a plurality of focus detection areas shown in FIG. 5A. The controller 30 detects the position and inclination of the AF image detection area on the image sensor 6 for capturing image signals corresponding to the A image “select-a” and the B image “select-b” on the focus detection area “select”. The angle θ1 is calculated based on information regarding the imaging optical system 10.

  Next, an image signal from the calculated AF image detection area is taken in, and the focus shift amount (defocus amount) is calculated by the method described above.

  As described above, not only the focus detection area at the center of the screen but also the focus detection area at the peripheral part can be accurately detected by the TTL phase difference detection method.

  6A and 6B show the configuration of the focus detection state at the tele end of the optical apparatus of the present embodiment. FIG. 6A shows a side cross-section of the optical instrument, and FIG. 6B shows a horizontal cross-section of the optical instrument.

  The light beams 1a and 1b shown in FIG. 6B make an angle in the horizontal direction with respect to the normal line of the light receiving surface when incident on the light receiving surface of the image sensor 6, so that the image shift in the horizontal direction is caused by the focus shift. appear. However, as shown in FIG. 6A, when the light beams 1a and 1b are incident on the light receiving surface of the image sensor 6, the angle formed with respect to the normal to the light receiving surface is as shown in FIG. 1B (wide end) in the vertical direction. Is the opposite angle. For this reason, the image shift in the vertical direction due to the focus shift occurs in the direction opposite to the wide end.

  FIG. 7A shows an AF image detection area at the tele end. Similar to the wide end shown in FIG. 3A, the tilt angle θ2 of the AF image detection area is made to coincide with the angle of the shift direction of the AF image. For this reason, the controller 30 obtains the angle of the AF image displacement direction based on the information related to the imaging optical system 10, and determines the tilt angle θ2 so as to coincide with the obtained displacement direction angle. Then, as shown in FIG. 7B, the vertical shift amount for each pixel block group described above is set so that the tilt angle θ2 is obtained.

  Then, the amount of shift of the AF image can be detected by performing addition processing so that the pixel blocks 61a1 and 61b1 shown in FIG. 3C are used as unit pixels in AF image detection to generate single image information.

  8A and 8B show how multipoint focus detection is performed at the tele end. FIG. 8A shows a focus detection area (small rectangular frame) in multipoint focus detection, and FIG. 8B shows AF images (A and B images) 7a and 7b formed by light beams that have passed through the separation pupils 41a and 41b. An example is shown.

  A case will be described in which a photographer selects a focus detection area (focus detection area indicated by “select”) at the center of the screen from a plurality of focus detection areas shown in FIG. 8A. The controller 30 detects the position of the AF image detection area on the image sensor 6 for capturing image signals corresponding to the A image “select-a” and the B image “select-b” on the focus detection area “select”, and the position thereof. The tilt angle θ2 is calculated based on information regarding the imaging optical system 10.

  Next, an image signal from the calculated AF image detection area is taken in, and the focus shift amount (defocus amount) is calculated by the method described above.

  As described above, the TTL phase difference detection type focus detection can be accurately performed on an arbitrary focus detection area including the focus detection area at the center of the screen.

  The controller 30 calculates the addresses of the pixel blocks 61a and 61b corresponding to the zoom position of the imaging optical system, and determines the focus position of the focus lens included in the imaging optical system 10 based on the detected amount of focus deviation. calculate. Then, the focus lens is driven via an actuator (not shown). In this way, TTL phase difference detection AF in the entire zoom region is possible. At this time, since the paired AF image information (image signal) is obtained from the image sensor 6, the drive direction and drive amount of the focus lens can be quantitatively calculated.

  As described above, according to the present embodiment, the inclination angles θ <b> 1 and θ <b> 2 of the photoelectric conversion region that captures a signal corresponding to the AF image in the image sensor 6 are changed based on the information related to the imaging optical system 10. Thereby, even when an AF image is formed obliquely on the image sensor 6, high focus detection performance can be obtained.

  In addition, according to the present embodiment, a secondary imaging optical sensor such as a conventional secondary imaging AF dedicated sensor and a secondary imaging optical system such as a separate lens associated therewith are not required. For this reason, the configuration of the optical apparatus can be simplified. Furthermore, in the case of having a secondary imaging optical system, the displacement of the relative position (optical axis position) between the imaging optical system and the secondary imaging optical system causes the AF performance to deteriorate. There are few anxiety factors by such a structure, and stable AF performance is obtained.

  Each embodiment described above is only a representative example, and various modifications and changes can be made to each embodiment in carrying out the present invention. For example, in the above-described embodiment, the case where both the first and second light beams are deflected has been described. However, only one of the light beams may be deflected with respect to the other light beam.

1 is a side cross-sectional view showing a configuration at a wide end of an optical apparatus that is an embodiment of the present invention. The horizontal sectional view which shows the structure in the wide end of the optical apparatus of an Example. The schematic diagram of the optical deflection | deviation unit used for an Example. The figure which shows the AF image detection area on the image pick-up element in the wide end of an Example. FIG. 3B is an enlarged view of the AF image detection area shown in FIG. 3A. The figure which shows the pixel block which comprises the AF image detection area shown to FIG. 3A. FIG. 6 is a diagram for explaining the inclination of the subject image and the shift amount of the AF image in the wide end and the front pin state of the embodiment. FIG. 4B is a diagram showing the amount of shift of the AF image in the AF image detection area in the state shown in FIG. 4A. FIG. 6 is a diagram for explaining the inclination of the subject image and the amount of shift of the AF image in the wide end and the focused state according to the embodiment. FIG. 4B is a diagram showing the amount of AF image shift within the AF image detection area in the state shown in FIG. 4C. FIG. 6 is a diagram for explaining the inclination of the subject image and the shift amount of the AF image in the wide end and rear pin states according to the embodiment. FIG. 4B is a diagram showing an AF image shift amount in an AF image detection area in the state shown in FIG. 4E. The figure explaining the multipoint focus detection in the wide end of an Example. The figure explaining the multipoint focus detection in the wide end of an Example. Side surface sectional drawing which shows the structure in the tele end of the optical apparatus which is an Example of this invention. The horizontal sectional view which shows the structure in the tele end of the optical apparatus of an Example. The figure which shows the AF image detection area on the image pick-up element in the tele end of an Example. FIG. 7B is an enlarged view of the AF image detection area shown in FIG. 7A. The figure explaining the multipoint focus detection in the tele end of an Example. The figure explaining the multipoint focus detection in the tele end of an Example. Side surface sectional drawing which shows the structure (imaging state) of the optical apparatus to which the technique used as the foundation of an Example is applied. FIG. 9B is a side sectional view showing the configuration (focus detection state) of the optical apparatus shown in FIG. 9A. FIG. 9B is a schematic diagram of an optical deflection unit used in the optical apparatus of FIG. 9A. The figure which shows the AF image detection area on the image pick-up element in the optical apparatus of FIG. 9A. FIG. 11B is an enlarged view of the AF image detection area shown in FIG. 11A. The figure which shows the pixel block which comprises the AF image detection area shown to FIG. 11A. FIG. 9B is a diagram showing an example of an AF image formed by a separation pupil in the optical apparatus shown in FIG. 9A. FIG. 9B is a view for explaining the inclination of the subject image and the shift amount of the AF image in the front pin state in the optical apparatus shown in FIG. 9A. The figure which shows the deviation | shift amount of AF image in the AF image detection area in the state shown to FIG. 13A. FIG. 9B is a view for explaining the inclination of the subject image and the shift amount of the AF image in the focused state in the optical apparatus shown in FIG. 9A. The figure which shows the deviation | shift amount of AF image within the AF image detection area in the state shown to FIG. 13C. FIG. 9B is a diagram for explaining the inclination of the subject image and the shift amount of the AF image in the rear pin state in the optical apparatus shown in FIG. 9A. The figure which shows the deviation | shift amount of AF image within the AF image detection area in the state shown to FIG. 13E.

Explanation of symbols

1a, 1b Luminous flux 6, 106 Image sensor 7a, 7b, 107a, 107b AF image 10, 110 Imaging optical system 40, 140 Optical deflection unit 41a, 41b, 141a, 141b Separating pupil 61a, 61b, 161a, 161b AF image detection area

Claims (3)

At least one of the first light beam and the second light beam that passes through the first region and the second region in the exit pupil of the optical system and reaches the photoelectric conversion element is compared with the other light beam. Deflection optical means for deflecting in a direction different from the separation direction of the first and second regions;
Focus detection means for detecting a focus state of the optical system based on a signal obtained from the photoelectric conversion element in accordance with the first image and the second image formed by the first and second light beams; Have
The focus detection unit is configured to change an inclination angle of a photoelectric conversion region that takes in signals corresponding to the first and second images of the photoelectric conversion element based on information about the optical system. Optical equipment.   The focus detection unit obtains an angle in a displacement direction of the first and second images on the photoelectric conversion element according to a change in a focus state of the optical system based on information on the optical system, and the photoelectric conversion The optical apparatus according to claim 1, wherein an inclination angle of the region is matched with an angle in the displacement direction. Each of the photoelectric conversion regions includes a plurality of pixel columns each composed of a plurality of pixels arranged in the separation direction,
The focus detection unit changes the tilt angle by shifting at least some of the plurality of pixel columns in a direction different from the separation direction with respect to other pixel columns. The optical apparatus according to claim 1 or 2.