Electronic device, its control method, and program

Abstract

To provide an electronic device capable of displaying an image in a display area of an appropriate size for a user.SOLUTION: An electronic device includes a display unit for displaying an image, an eyepiece optical system for observing the display unit, an acquiring unit for acquiring a distance from the eyepiece optical system to an eye, and a control unit for controlling the display unit to change a display area of the display unit on the basis of a distance from the eyepiece optical system to the eye.SELECTED DRAWING: Figure 10

Description

[Technical Field]

[0001] The present invention relates to a technique for changing the display area of ​​a display provided in an electronic device. [Background technology]

[0002] Some models of imaging devices, such as digital cameras and video cameras, use an electronic viewfinder (EVF) to view the subject. An electronic viewfinder is configured so that a small display installed inside the camera is magnified through an eyepiece optical system consisting of multiple lenses. The user can observe the magnified display image by looking through this eyepiece optical system.

[0003] In recent years, there has been a trend toward higher magnification displays in camera viewfinders. Higher magnification allows you to see a larger image, making it easier to check the focus. A viewfinder with a larger field of view also increases the sense of immersion, making photography more enjoyable.

[0004] However, when the distance from the viewfinder to the eye is long (for example, when looking through the viewfinder while wearing glasses), if the display area is too large, part of the display area is likely to be obscured, reducing visibility and making it difficult to grasp the composition.

[0005] As one solution to this problem, Patent Document 1 discloses a technique that allows the user to arbitrarily set the display area of ​​the finder. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-016669 Summary of the Invention [Problem to be solved by the invention]

[0007] However, with the conventional technology disclosed in Patent Document 1, changing the viewfinder display area requires operations from a hierarchical menu, which poses a problem for users who sometimes take photos with glasses and sometimes without glasses, as changing the display area can be cumbersome.

[0008] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide an electronic device that can display an image in a display area of ​​an appropriate size for the user. [Means for solving the problem]

[0009] The electronic device according to the present invention comprises a display means for displaying an image, an eyepiece optical system for observing the display means, a measuring means for measuring the distance from the eyepiece optical system to the eye; a control means for controlling the display means so as to change a display area of ​​the display means based on a distance from the eyepiece optical system to the eye; an eye-contact detection means for detecting the presence of the infrared light by receiving diffused reflection light from the user's eye; Equipped with the measuring means measures the distance from the eyepiece optical system to the eye when the amount of reflected light received by the eyepiece detecting means is stable and exceeds an eyepiece threshold; The control means sets the display area to a first size when the distance from the eyepiece optical system to the eye is a first distance, and sets the display area to a second size smaller than the first size when the distance from the eyepiece optical system to the eye is a second distance longer than the first distance. [Effects of the Invention]

[0010] According to the present invention, it is possible to display an image in a display area of ​​an appropriate size for the user. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a diagram showing the appearance of a digital camera with interchangeable lenses that is a first embodiment of an electronic device of the present invention. [Figure 2] FIG. 1 is a cross-sectional view of a camera according to a first embodiment. [Figure 3] FIG. 1 is a cross-sectional view of an optical system including a line-of-sight detection mechanism. [Figure 4] FIG. 1 is a perspective view of an optical system including a line-of-sight detection mechanism. [Figure 5] FIG. 10 is a diagram illustrating an optical path when detecting a line of sight using a line of sight detection mechanism. [Figure 6] Schematic diagram for explaining the principle of a visual field detection method. [Figure 7] FIG. 1 is a schematic diagram showing an eye image. [Figure 8] 10 is a flowchart showing a gaze detection operation. [Figure 9] FIG. 2 is a schematic diagram showing the distance from the final surface of the eyepiece optical system to the eye. [Figure 10] 5A and 5B are schematic diagrams showing how to change the display area of ​​a display device. [Figure 11] 10 is a schematic diagram showing how the display of the index used for calibration is changed based on the distance from the final surface of the eyepiece optical system to the eye. [Figure 12] 10 is a flowchart showing an operation of changing the display area of ​​a display device. [Figure 13] FIG. 10 is a schematic diagram showing how to change the display area of ​​a display device in the second embodiment. [Figure 14] 10 is a flowchart showing an operation of changing the display area of ​​a display device according to the third embodiment. [Figure 15] 10 is a flowchart showing an operation of changing the display area of ​​a display device in the fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the scope of the invention claimed. Although multiple features are described in the embodiments, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant explanations will be omitted.

[0013] (First embodiment) <Configuration explanation> 1 is a diagram showing the appearance of an interchangeable-lens digital camera 1 (hereinafter, "camera"), which is a first embodiment of an electronic device of the present invention. Note that the electronic device referred to in the present invention is not limited to a digital camera, but also includes any electronic device that displays information such as images and text, and that can detect the line of sight of a user viewing an optical image through an eyepiece optical system. These electronic devices may include, for example, mobile phones, game consoles, tablet devices, personal computers, watch-type or eyeglass-type information terminals, head-mounted displays, binoculars, and the like.

[0014] FIG. 1(a) is a front perspective view of the camera 1, and FIG. 1(b) is a rear perspective view of the camera 1. As shown in FIG.

[0015] As shown in Fig. 1(a), camera 1 has a photographing lens unit 1A and a camera body 1B. A release button 5, which is an operating member that accepts image capture operations from the user (photographer), is disposed on the camera body 1B. As shown in Fig. 1(b), an eyepiece window frame 121 is disposed on the back of camera body 1B, through which the user can look into a display device 6 (see Fig. 3), which will be described later and is included within camera body 1B.

[0016] The display unit in this embodiment includes a display device 6. An eyepiece window frame 121 forms an eyepiece 13 and protrudes outward (toward the rear side) relative to the camera body 1B. Operation members 41 to 43 that accept various operations from the user are also arranged on the rear side of the camera body 1B. For example, operation member 41 is a touch panel that accepts touch operations by the user, operation member 42 is an operation lever that can be pushed down in each direction, and operation member 43 is a four-way key that can be pressed in each of four directions. Operation member 41 (touch panel) is equipped with a display panel 40 (see FIG. 3) such as a liquid crystal panel, and has the function of displaying images.

[0017] 2 is a side cross-sectional view of camera 1 of this embodiment, showing the electrical block configuration within camera 1. Camera body 1B has an image sensor 2 that captures a subject image. Image sensor 2 is an image sensor formed, for example, by a CCD or CMOS sensor, and photoelectrically converts an optical image formed on the imaging surface of image sensor 2 by the optical system of photographing lens unit 1A, A / D converts the resulting analog image signal, and outputs it as image data.

[0018] Photographing lens unit 1A is configured with an optical system including a zoom lens, a focus lens, an aperture, etc., and when attached to camera body 1B, it guides a light beam from a subject to image sensor 2 and forms an image of the subject on the imaging surface of image sensor 2. Aperture control unit 118, focus adjustment unit 119, and zoom control unit 120 each receive instruction signals from CPU 3 via mount contact unit 117, and drive and control the aperture, focus lens, and zoom lens in accordance with those instruction signals.

[0019] The CPU 3 included in the camera body 1B reads out a control program for each block included in the camera body 1B from the ROM included in the memory unit 4, and loads and executes the program in the RAM included in the memory unit 4. In this way, the CPU 3 controls the operation of each block included in the camera body 1B. The CPU 3 is connected to a gaze detection unit 201, a photometry unit 202, an autofocus detection unit 203, a signal input unit 204, an eye proximity detection unit 208, a distance calculation unit 209, a display device drive unit 210, a light source drive unit 205, and the like. The CPU 3 also transmits signals to an aperture control unit 118, a focus adjustment unit 119, and a zoom control unit 120, which are arranged in the photographing lens unit 1A, via a mount contact 117. In this embodiment, the memory unit 4 has a function of storing image signals from the image sensor 2 and the gaze detection sensor 30.

[0020] The gaze detection unit 201 A / D converts the output of the gaze detection sensor 30 (CCD-EYE) (eye image captured from the eyeball) when an eyeball image is formed on the gaze detection sensor 30, and sends the result to the CPU 3. The CPU 3 extracts feature points required for gaze detection from the eye image according to a predetermined algorithm described later, and calculates the user's gaze (the gaze point in the visual image) from the positions of the feature points.

[0021] 9, the distance calculation unit 209 calculates the distance 32 from the final surface of the eyepiece optical system 16 to the eye based on the coordinates of the corneal reflection image on the gaze detection sensor 30, and transmits the output value to the CPU 3. Note that the distance calculation unit 209 may acquire the distance 32 from a table in which the distance 32 from the final surface of the eyepiece optical system 16 to the eye is calculated in advance based on the coordinates of the corneal reflection image.

[0022] The display device driving unit 210 determines the display area of ​​the display device 6 based on the distance calculated by the distance calculation unit 209 and performs display. The eye proximity detection unit 208 sends the output of the eye proximity detection sensor 50 to the CPU 3. The CPU 3 calculates whether or not the user has placed their eye close to the display device 6 in accordance with a predetermined algorithm, which will be described later. The light source driving unit 205 drives the infrared LEDs 18 to 27, which are light sources, in accordance with commands from the CPU 3 so that the light emission intensity is set to a predetermined value.

[0023] The photometry unit 202 amplifies, logarithmically compresses, and A / D converts the signal obtained from the image sensor 2, which also functions as a photometry sensor, specifically the luminance signal corresponding to the brightness of the field, and sends the result to the CPU 3 as field luminance information.

[0024] The autofocus detection unit 203 A / D converts signal voltages from multiple detection elements (multiple sub-pixels) used for phase difference detection, which are included in the pixels of the image sensor 2, and sends the converted signal to the CPU 3. The CPU 3 calculates the distance to the subject corresponding to each focus detection point from the signals from the multiple detection elements. This is a well-known technique known as image plane phase difference AF. In this embodiment, as an example, the field of view image (visual image) in the viewfinder is divided, and a focus detection point is located at each of the 180 divided locations on the image plane.

[0025] The image processing unit 206 performs various types of image processing on the image data stored in the RAM in the memory unit 4. Specifically, it executes various types of image processing for developing, displaying, and recording digital image data, such as correction of pixel defects caused by the optical system or image sensor, demosaicing, white balance correction, color interpolation, and gamma processing.

[0026] The signal input unit 204 is connected to a switch SW1 that is turned on by the first stroke of the release button 5 to start photometry, focus detection, line of sight detection, and other operations of the camera 1, and a switch SW2 that is turned on by the second stroke of the release button 5 to start a photographing operation. ON signals from the switches SW1 and SW2 are input to the signal input unit 204 and transmitted to the CPU 3. The signal input unit 204 also accepts operation inputs from the operation members 41 (touch panel), 42 (buttons), and 43 (up, down, left, and right keys) shown in FIG. 1(b).

[0027] The recording / output unit 207 records data including image data on a recording medium such as a removable memory card, or outputs this data to an external device via an external interface.

[0028] FIG. 3 is a cross-sectional view of the optical system including the line-of-sight detection mechanism in this embodiment, and is a diagram in which the camera 1 is cut along the YZ plane formed by the Y axis and Z axis shown in FIG. 1(a).

[0029] The shutter 44 and the image sensor 2 are aligned in order along the optical axis of the photographing lens unit 1A. A display panel 40 is provided on the back of the camera body 1B, and is used to display menus and images for operating the camera 1 and viewing and editing images captured by the camera 1. The display panel 40 is composed of a backlit liquid crystal panel, an organic EL panel, or the like.

[0030] The panel holder 7 is a panel holder that holds a display device 6 that is configured of an organic EL panel or the like, and is adhesively fixed to the display device 6 to form a display panel unit 8.

[0031] The first optical path splitting prism 9 and the second optical path splitting prism 10 are attached and bonded to form an optical path splitting prism unit 11 (optical path splitting member). The optical path splitting prism unit 11 guides the light beam from the display device 6 to an eyepiece window 17 provided in the user's viewing hole 13, and conversely guides reflected light from the eye (pupil) guided through the eyepiece window 17 to an eye-gaze detection sensor 30 shown in Fig. 4. The display panel unit 8 and the optical path splitting prism unit 11 are fixed with a mask 12 sandwiched between them and are integrally formed.

[0032] The eyepiece optical system 16 is composed of a G1 lens 13, a G2 lens 14, and a G3 lens 15. The electronic viewfinder is configured so that the display panel unit 8 appears magnified through the eyepiece optical system 16, allowing the user to observe the magnified display image.

[0033] The eyepiece window 17 is a transparent member that transmits visible light. The image displayed on the display panel unit 8 is observed through the optical path splitting prism unit 11, the eyepiece optical system 16, and the eyepiece window 17.

[0034] The illumination windows 20 and 21 are windows for concealing the infrared LEDs 18 and 19 so that they cannot be seen from the outside, and are made of a resin that absorbs visible light and transmits infrared light.

[0035] The EVF (electronic viewfinder) provided on the camera body 1B in this embodiment is capable of displaying menus and images as a normal EVF, like the display panel 40, and is also configured to detect the line of sight of the user looking into the EVF and reflect the detection results in the control of the camera 1.

[0036] Like display panel 40, display device 6 is used to display menus and images for operating camera 1 and viewing and editing images captured by camera 1 while the user is looking through the viewfinder. Display device 6 is configured as a backlit liquid crystal panel, an organic EL panel, or the like.

[0037] 4A and 4B are a perspective view and a cross-sectional view of the optical system including the line-of-sight detection mechanism in this embodiment, respectively. Fig. 4A is a perspective view showing the configuration of the EVF in this embodiment, and Fig. 4B is a cross-sectional side view of the optical axis of the EVF.

[0038] The eyepiece window 17 is a transparent member that transmits visible light. The image displayed on the display panel 6 is observed through the optical path splitting prism unit 11, the eyepiece optical system 16, and the eyepiece window 17.

[0039] The infrared LEDs 18, 19, 22, 23, 24, 25, 26, and 27 are arranged so as to irradiate infrared light toward the user's viewing hole 13 at different positions and attitudes. The illumination windows 20 and 21 are windows that conceal the infrared LEDs 18, 19, 22, 23, 24, 25, 26, and 27 so that they cannot be seen from the outside, and are made of a resin that absorbs visible light and transmits infrared light.

[0040] Infrared LEDs 18, 19, 23, and 25 are infrared LEDs for short-distance illumination. Infrared LEDs 22, 24, 26, and 27 are infrared LEDs for long-distance illumination. The gaze detection optical system, which includes diaphragm 28 and gaze imaging lens 29, further guides the infrared reflected light guided from eyepiece window 17 by optical path splitting prism unit 11 to gaze detection sensor 30. Gaze detection sensor 30 is composed of a solid-state image sensor such as a CCD or CMOS sensor.

[0041] The eye proximity detection sensor 50 is composed of a photodiode and other components that can be driven with less power than the gaze detection sensor 30. The infrared LED 22 for gaze detection also serves as the infrared LED for eye proximity detection. The infrared LED 22 illuminates the user's eye, and the eye proximity detection sensor 50 receives diffuse reflected light from the user.

[0042] In Figure 4(b), an image of the user's eyeball, illuminated by an infrared LED, passes through the eyepiece window 17, G3 lens 15, G2 lens 14, and G1 lens 13, and enters the second optical path splitting prism 10 from its second surface 10a. This optical path is indicated by 31a. A dichroic film that reflects infrared light is formed on the first surface 10b of the second optical path splitting prism.

[0043] An eyeball image illuminated by at least one of the infrared LEDs shown in Fig. 4(a) is reflected by first surface 10b toward second surface 10a. This reflected light path is indicated by 31b. The infrared light that has traveled along reflected light path 31b is totally reflected by second surface 10a, travels along imaging light path 31c, passes through aperture 28, and is imaged on gaze detection sensor 30 by gaze imaging lens 29.

[0044] For gaze detection, the corneal reflection image formed by specular reflection of the infrared LEDs from the cornea is used in addition to the eyeball image generated by illumination. Figure 5 shows an example of the optical path of light emitted from the infrared LEDs 18, 19, 23, and 25 for short-distance illumination, which is specularly reflected by the cornea 611 of the eyeball and received by the gaze detection sensor 30.

[0045] <Explanation of gaze detection operation> The gaze detection method will be described with reference to FIGS. 6, 7(a), 7(b), and 8. FIG.

[0046] FIG. 6 is a diagram for explaining the principle of the line-of-sight detection method, and is a schematic diagram of an optical system for performing line-of-sight detection.

[0047] 6, light sources 601a and 601b are arranged approximately symmetrically with respect to the optical axis of light receiving lens 618 (corresponding to line-of-sight imaging lens 29 in FIG. 4(b)), and illuminate a user's eyeball 610. A portion of the light emitted from light sources 601a and 601b and reflected by eyeball 610 is collected by light receiving lens 618 onto line-of-sight detection sensor 620 (corresponding to line-of-sight detection sensor 30 in FIGS. 4 and 5).

[0048] Fig. 7(a) is a schematic diagram of an eye image captured by the gaze detection sensor 620 (eyeball image projected onto the gaze detection sensor 620), and Fig. 7(b) is a diagram showing the output intensity of the image sensor in the gaze detection sensor 620. Fig. 8 is a schematic flowchart of the gaze detection operation.

[0049] 8, when the gaze detection operation is started, CPU 3 causes light sources 601a and 601b to emit light, and irradiates infrared light with emission intensity E2 for gaze detection toward user's eyeball 610. An image of the user's eyeball illuminated by the infrared light is formed on gaze detection sensor 620 through light receiving lens 618, and is photoelectrically converted by gaze detection sensor 620. As a result, a processable electrical signal of the eye image is obtained.

[0050] In step S802, the CPU 3 uses the gaze detection unit 201 to acquire an eye image (eye image signal; electric signal of the eye image) from the gaze detection sensor 620.

[0051] In step S803, the CPU 3 obtains the coordinates of the points corresponding to the corneal reflection images Pd and Pe of the light sources 601a and 601b and the pupil center c from the eye image obtained in step S802.

[0052] Infrared light emitted from light sources 601a and 601b illuminates a cornea 611 of a user's eyeball 610. At this time, corneal reflection images Pd and Pe formed by a portion of the infrared light reflected from the surface of the cornea 611 are collected by a light receiving lens 618 and formed on a gaze detection sensor 620 as corneal reflection images Pd' and Pe' in the eye image. Similarly, light beams from edges a and b of a pupil 612 are also formed on the gaze detection sensor 620 as pupil edge images a' and b' in the eye image.

[0053] Figure 7(b) is a diagram showing luminance information (luminance distribution) of region α' in the eye image of Figure 7(a). In Figure 7(b), the horizontal direction of the eye image is the X-axis direction and the vertical direction is the Y-axis direction, and the luminance distribution in the X-axis direction is shown. In this embodiment, the coordinates of the corneal reflection images Pd' and Pe' in the X-axis direction (horizontal direction) are Xd and Xe, and the coordinates of the pupil edge images a' and b' in the X-axis direction are Xa and Xb.

[0054] As shown in FIG. 7( b), an extremely high level of luminance is obtained at the coordinates Xd and Xe of the corneal reflection images Pd' and Pe'. In the region from coordinate Xa to coordinate Xb, which corresponds to the region of the pupil 612 (the region of the pupil image obtained when the light beam from the pupil 612 is focused on the gaze detection sensor 620), an extremely low level of luminance is obtained except for coordinates Xd and Xe. In the region of the iris 613 outside the pupil 612 (the region of the iris image outside the pupil image obtained when the light beam from the iris 613 is focused), a luminance intermediate between the above two types of luminance is obtained. Specifically, a luminance intermediate between the above two types of luminance is obtained in the region where the X coordinate (coordinate in the X-axis direction) is smaller than coordinate Xa and the region where the X coordinate is larger than coordinate Xb.

[0055] From the luminance distribution shown in FIG. 7(b), the X-coordinates Xd and Xe of the corneal reflection images Pd' and Pe' and the X-coordinates Xa and Xb of the pupil edge images a' and b' can be obtained. Specifically, the coordinates of the corneal reflection images Pd' and Pe' can be obtained as the coordinates of extremely high luminance, and the coordinates of the pupil edge images a' and b' can be obtained as the coordinates of extremely low luminance. Furthermore, when the rotation angle θx of the optical axis of the eyeball 610 relative to the optical axis of the light receiving lens 618 is small, the coordinate Xc of the pupil center image c' (center of the pupil image) obtained when the light beam from the pupil center c is focused on the gaze detection sensor 30 can be expressed as Xc ≒ (Xa + Xb) / 2. In other words, the coordinate Xc of the pupil center image c' can be calculated from the X-coordinates Xa and Xb of the pupil edge images a' and b'. In this way, the coordinates of the corneal reflection images Pd' and Pe' and the coordinates of the pupil center image c' can be estimated.

[0056] In step S804, CPU 3 calculates the imaging magnification β of the eyeball image. The imaging magnification β is determined by the position of eyeball 610 relative to light receiving lens 618, and can be calculated using a function of the distance (Xd-Xe) between corneal reflection images Pd' and Pe'.

[0057] In step S805, CPU 3 calculates the rotation angle of the optical axis of eyeball 610 relative to the optical axis of light receiving lens 618. The X coordinate of the midpoint between corneal reflection images Pd and Pe and the X coordinate of the center of curvature O of cornea 611 approximately coincide. Therefore, if the standard distance from the center of curvature O of cornea 611 to the center c of pupil 612 is Oc, then rotation angle θX of eyeball 610 in the ZX plane (plane perpendicular to the Y axis) can be calculated using the following (Equation 1). Rotation angle θy of eyeball 610 in the ZY plane (plane perpendicular to the X axis) can also be calculated using a method similar to that for calculating rotation angle θx.

[0058] β×Oc×SINθX≒{(Xd+Xe) / 2}-Xc…(Formula 1) In step S806, the CPU 3 uses the rotation angles θx, θy calculated in step S805 to determine (estimate) the user's viewpoint (the position where the line of sight is fixed; the position where the user is looking) in the viewing image displayed on the display device 6. If the coordinates (Hx, Hy) of the viewpoint are coordinates corresponding to the pupil center c, the coordinates (Hx, Hy) of the viewpoint can be calculated using the following (Equation 2) and (Equation 3).

[0059] Hx=m×(Ax×θx+Bx) …(Formula 2) Hy = m × (Ay × θy + By) ... (Equation 3) The parameter m in (Equation 2) and (Equation 3) is a constant determined by the configuration of the finder optical system (light receiving lens 618, etc.) of the camera 1, and is a conversion coefficient that converts the rotation angles θx and θy into coordinates corresponding to the pupil center c in the visual image, and is determined in advance and stored in the memory unit 4. The parameters Ax, Bx, Ay, and By are gaze correction parameters that correct individual differences in gaze, and are acquired by performing calibration and stored in the memory unit 4 before the gaze detection operation starts.

[0060] Calibration is a process to acquire the characteristics of the user's eyes, and is applied when calculating the coordinates of the viewpoint from the rotation angle. Correction parameters for sensitivity and visual axis deviation are calculated based on eye images taken when the user gazes at multiple indices. Sensitivity is corrected using the above parameters Ax and Ay, and visual axis deviation is corrected using the above parameters Bx and By.

[0061] In step S807, the CPU 3 stores the coordinates (Hx, Hy) of the viewpoint in the memory unit 4, and ends the line-of-sight detection operation.

[0062] FIG. 9 is a diagram showing the distance 32 from the final surface of the eyepiece optical system to the eye.

[0063] The distance 32 from the final surface of the eyepiece optical system 16 to the eye can be calculated using the coordinates of the corneal reflection images Pd' and Pe' and a function of the distance between the two points. This function is created based on simulations or measurements using an actual device.

[0064] 10(a) and 10(b) are diagrams showing how to change the display area of ​​the display.

[0065] The display area in this embodiment refers to the area where the OLEDs (Organic Light Emitting Diodes) are actually emitting light out of the entire displayable area where the OLEDs are arranged. The display area of ​​the display is changed based on the distance 32 from the final surface of the eyepiece optical system 16 to the user's eye.

[0066] As shown in FIG. 10(a), if the user's eye is close to the eyepiece optical system, the display area is widened. FIG. 10(a) shows a state in which the entire displayable area is used for display. Conversely, as shown in FIG. 10(b), if the user's eye is farther from the eyepiece optical system, the display area is narrowed. Note that in this embodiment, it is assumed that the closer the distance between the user's eye and the eyepiece optical system, the wider the display area is set, and the farther the distance, the narrower the display area is set. However, if the distance between the user's eye and the eyepiece optical system is equal to or less than a predetermined threshold, the display area may be widened (e.g., the entire displayable area), and if the distance is greater than the predetermined threshold, the display area may be narrower than when the distance is equal to or less than the predetermined threshold. Alternatively, multiple such thresholds may be set, and the display area may be changed in stages around the threshold.

[0067] In this embodiment, when the display area is changed, both the OSD (On Screen Display) display and the live view display are changed. The OSD display is intended to show camera settings at the time of shooting, such as aperture and shutter speed, and information such as the remaining battery level.

[0068] 11(a) and 11(b) are diagrams showing that the display of the index used for calibration (CAL) is changed based on the distance 32 from the final surface of the eyepiece optical system 16 to the eye.

[0069] In this embodiment, during calibration of gaze detection, the distance 32 from the final surface of the eyepiece optical system 16 to the eye is measured while the user is looking at the central target, and the calibration content is changed based on that distance. During calibration of gaze detection, the user is required to gaze at multiple specified targets for a certain period of time.

[0070] As shown in Figure 11(a), if the user's eye is close to the eyepiece optical system, the placement of the peripheral indices is changed based on that distance. During calibration, the accuracy of the peripheral indices can be improved the higher the image height from the optical axis of the eyepiece optical system 16. When the distance 32 from the final surface of the eyepiece optical system 16 to the eye is short, the display area that the user can stably view is wide, so it is possible to place the peripheral indices diagonally as shown in Figure 11(a) and ensure the image height of the peripheral indices.

[0071] As shown in Figure 11(b), if the user's eye is far from the eyepiece optical system 16, the image height of the peripheral indices is changed to a lower value based on that distance. The display area that the user can stably view changes depending on the measured distance 32 from the final surface of the eyepiece optical system 16 to the eye. For example, if the distance is short, the area that can be stably viewed will be wider, and if the distance is long, the area that can be stably viewed will be narrower. Therefore, by placing the peripheral indices within that area, it is possible to ensure that the user focuses on the peripheral indices.

[0072] 12 is a flowchart showing the operation of changing the display area of ​​the display. This operation starts in step S1201 when the user turns on the power of camera 1.

[0073] In step S1202, the CPU 3 displays, for example, on the display panel 40, a message asking the user whether or not to perform calibration.

[0074] If the user answers "I want to perform calibration," the CPU 3 advances the process to step S1203 and performs calibration, at which point it calculates the distance 32 from the final surface of the eyepiece optical system 16 to the eye.

[0075] In step S1204, the CPU 3 determines the display area of ​​the display that is optimized for the user based on the distance 32 from the final surface of the eyepiece optical system 16 to the eye calculated in step S1203.

[0076] If the user answers "Do not perform calibration" in step S1202, CPU 3 proceeds to step S1205. In step S1205, CPU 3 reads the display area determined when calibration was previously performed. At this time, the user is prompted to select user-specific calibration data.

[0077] In step S1206, CPU 3 determines the display area based on the display area read out in step S1205.

[0078] In step S1207, CPU 3 actually changes the display area of ​​display device 6 based on the determined display area.

[0079] As described above, in this embodiment, the display area of ​​the display unit in the electronic device is changed based on the distance from the final surface of the eyepiece optical system to the eye. Specifically, if the distance is short, the display area is made larger, and if the distance is long, the display area is made smaller. This allows images to be displayed in the optimal display area for the user without having to perform cumbersome settings, etc.

[0080] In this embodiment, the corneal reflection image is used to calculate the distance from the final surface of the eyepiece optical system to the eye. It is possible to calculate the distance from the final surface of the eyepiece optical system to the eye based on the coordinates of the corneal reflection image in the image acquired by the gaze detection sensor. This eliminates the need for a special distance calculation device, compared to a configuration in which a gaze detection device and a distance calculation device are separately provided. This prevents the device from becoming too complicated or large, and allows for a more inexpensive configuration.

[0081] Furthermore, in this embodiment, during calibration for gaze detection, the display of the index used for calibration is changed depending on the distance from the final surface of the eyepiece optical system to the eye. This improves the reliability and effectiveness of calibration compared to a configuration in which the display of the index used for calibration is not changed depending on the distance from the final surface of the eyepiece optical system to the eye. This is expected to improve the stability and accuracy of gaze detection.

[0082] In addition, in this embodiment, when the display area of ​​the display unit is changed, both the OSD display and the live view display are changed. This ensures visibility of not only the live view display but also the OSD display, compared to a configuration in which only the live view display is changed and the OSD display is kept constant. This makes it easier for users to grasp information such as camera settings and remaining battery level when shooting.

[0083] In addition, in this embodiment, the distance from the final surface of the eyepiece optical system to the eye is calculated during calibration of the gaze detection. This allows the user to obtain and record the distance specific to the user once, and from the next time onwards, simply by selecting the calibration data, the display area optimized for the user can be easily retrieved. This allows the user to quickly move on to shooting.

[0084] (Second embodiment) The second embodiment will be described below with reference to FIGS. 13(a) and 13(b).

[0085] In the first embodiment, when the display area of ​​the display is changed, both the OSD display and the live view display are changed. In contrast, in the second embodiment, when the display area is changed, only the live view display is changed and the OSD display is kept constant.

[0086] Fig. 13(a) shows the case where the eye is close to the eyepiece optical system, and Fig. 13(b) shows the case where the eye is far from the eyepiece optical system.

[0087] In this embodiment, the OSD display remains constant regardless of the distance from the camera to the eye, and only the display area of ​​the live view display changes. This ensures visibility of the live view display compared to a configuration in which both the OSD display and the live view display are changed, while preventing the font of characters indicating information such as camera settings and remaining battery power from becoming small and difficult to see.

[0088] (Third embodiment) The third embodiment will be described below with reference to FIG.

[0089] In the first embodiment, the distance 32 from the final surface of the eyepiece optical system 16 to the eye is calculated during calibration of the line of sight detection. In contrast, in the third embodiment, the distance is calculated after it is detected that the eye has been placed near the eye.

[0090] In step S1401 of FIG. 14, the CPU 3 detects the presence of an eye using the eye-contact detection unit 208.

[0091] In step S1402, CPU 3 determines whether the distance from the final surface of the eyepiece optical system 16 to the eye has stabilized. Here, CPU 3 determines whether the amount of reflected light received by the eyepiece detection sensor 50 has exceeded the eyepiece determination threshold and is stable. If the amount of reflected light has exceeded the eyepiece determination threshold and is stable, CPU 3 determines that the distance has stabilized, and proceeds to step S1403. On the other hand, if the amount of reflected light has not exceeded the eyepiece determination threshold or is not stable, CPU 3 determines that the distance has not stabilized, and repeats the process of step S1402 until the distance stabilizes.

[0092] In step S1403, the CPU 3 calculates the distance from the final surface of the eyepiece optical system 16 to the eye.

[0093] In step S1404, CPU 3 determines the display area of ​​the display based on the distance calculated in step S1403.

[0094] In step S1405, CPU 3 lights up the display based on the display area determined in step S1404.

[0095] In this embodiment, the distance from the final surface of the eyepiece optical system to the eye is calculated after it is detected that the user's eye is placed close to the camera. This calculates the distance and changes the display area each time the eye is placed close to the camera, allowing the display area to be optimized for the user's viewing style at that time.

[0096] (Fourth embodiment) The fourth embodiment will be described below with reference to FIG.

[0097] In the first embodiment, the distance 32 from the final surface of the eyepiece optical system 16 to the eye is calculated during calibration of the line of sight detection. In contrast, in the fourth embodiment, the distance is calculated when pressing a button for changing the display area is detected. In this embodiment, it is assumed that a button for changing the display area is provided on the surface of the camera body 1B.

[0098] In step S1501 of FIG. 15, the CPU 3 detects that a button for changing the display area of ​​the display has been pressed.

[0099] In step S1502, the CPU 3 calculates the distance 32 from the final surface of the eyepiece optical system 16 to the eye.

[0100] In step S1503, CPU 3 determines the display area of ​​the display based on the distance calculated in step S1502.

[0101] In step S1504, CPU 3 changes the display area of ​​the display based on the display area determined in step S1503.

[0102] In this embodiment, when the press of a button for changing the display area of ​​the display is detected, the distance from the final surface of the eyepiece optical system to the eye is calculated. This allows the distance to be calculated again when the user wants to change the display area, and the display can be displayed in an appropriate display area.

[0103] (Other embodiments) The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program.The present invention can also be realized by a circuit (e.g., ASIC) that realizes one or more functions.

[0104] The invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0105] 6: display device, 30: line-of-sight detection sensor, 32: distance from the final surface of the eyepiece optical system to the eye, 201: line-of-sight detection unit, 209: distance calculation unit, 210: display device driving unit

Claims

1. a display means for displaying an image; an eyepiece optical system for observing the display means; a measuring means for measuring the distance from the eyepiece optical system to the eye; a control means for controlling the display means so as to change a display area of ​​the display means based on a distance from the eyepiece optical system to the eye; an eye-contact detection means for detecting the presence of the infrared light by receiving diffused reflection light from the user's eye; Equipped with the measuring means measures the distance from the eyepiece optical system to the eye when the amount of reflected light received by the eyepiece detecting means is stable and exceeds an eyepiece threshold; The electronic device is characterized in that the control means sets the display area to a first size when the distance from the eyepiece optical system to the eye is a first distance, and sets the display area to a second size smaller than the first size when the distance from the eyepiece optical system to the eye is a second distance longer than the first distance.

2. 2. The electronic device according to claim 1, wherein the measuring means measures the distance from the eyepiece optical system to the eye using a corneal reflection image of the eye.

3. 2. The electronic device according to claim 1, wherein the control means changes the display area in stages according to the distance from the eyepiece optical system to the eye.

4. 4. The electronic device according to claim 2, further comprising a line-of-sight detection unit for detecting a line of sight, wherein the measurement unit measures the distance from the eyepiece optical system to the eye when calibrating the line-of-sight detection unit.

5. 5. The electronic device according to claim 4, wherein the line-of-sight detection means changes the display of the index used for calibration depending on the distance from the eyepiece optical system to the eye.

6. 4. The electronic device according to claim 2, wherein the measuring means measures the distance from the eyepiece optical system to the eye when an operating member for changing the display area of ​​the display means is operated.

7. 7. The electronic device according to claim 1, wherein the control unit changes both the OSD display and the live view display when changing the display area of ​​the display unit.

8. 7. The electronic device according to claim 1, wherein the control means, when changing the display area of ​​the display means, changes only the live view display and keeps the OSD display constant.

9. 9. The electronic device according to claim 1, further comprising an image capturing unit for capturing an image of a subject.

10. A method for controlling an electronic device that includes a display unit that displays an image and an eyepiece optical system for observing the display unit, comprising: a measuring step of measuring a distance from the eyepiece optical system to the eye; a control step of controlling the display means so as to change a display area of ​​the display means based on a distance from the eyepiece optical system to the eye; an eye-contact detection step of detecting the presence of the eye by receiving diffused reflection light of infrared light from the user's eye; and In the measuring step, when the amount of reflected light received in the eyepiece detection step is stable and exceeds an eyepiece threshold, the distance from the eyepiece optical system to the eye is measured, A control method for an electronic device, characterized in that, in the control process, when the distance from the eyepiece optical system to the eye is a first distance, the display area is set to a first size, and when the distance from the eyepiece optical system to the eye is a second distance longer than the first distance, the display area is set to a second size smaller than the first size.

11. A program for causing a computer to execute each step of the control method according to claim 10.

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