JP4460904B2 - Camera system, camera, and interchangeable lens - Google Patents

Description

  The present invention relates to an interchangeable lens camera and camera system having a TTL phase difference AF detection device, and more particularly to a technique for performing AF correction according to chromatic aberration of a photographing lens or the like.

  In a camera equipped with a TTL phase difference AF device, even if the focus of the taking lens is adjusted based on the focus information detected by the AF device, the image will be out of focus when taken under different light sources. There is. This is because a difference occurs in the best image plane position with respect to each light source due to the chromatic aberration characteristics of the photographing lens.

  Therefore, a technique for storing a correction amount (hereinafter referred to as AF correction data) of the best image plane position in accordance with the chromatic aberration characteristics in the photographing lens and correcting the output of the AF apparatus based on the AF correction data. Has been proposed (see, for example, Patent Document 1).

  By the way, in the interchangeable lens camera, it is possible to change the focal length by attaching an intermediate adapter between the camera and the interchangeable lens. As this intermediate adapter, for example, a teleconverter that increases the focal length is known.

When such an intermediate adapter is attached to the camera, the chromatic aberration of the intermediate adapter affects the focal position in the same manner as the chromatic aberration of the interchangeable lens. Therefore, a technique has been proposed in which the above-described AF correction data is stored in both the interchangeable lens and the intermediate adapter and combined to correct the output of the AF device (see, for example, Patent Document 2).
Japanese Patent Publication No. 3-73847 Japanese Patent No. 3340895

  However, since the technique described in Patent Document 2 simply synthesizes the AF correction data that each of the interchangeable lens and the intermediate adapter individually has, it is in a state where the interchangeable lens and the intermediate adapter are combined. Considering the final AF accuracy, it is insufficient. In other words, in order to realize higher-precision AF performance, it is considered desirable to determine AF correction data based on optical characteristics determined in a state where the interchangeable lens and the intermediate adapter are combined.

  The present invention has been made in view of the above-described situation. Even when an interchangeable lens is attached to an interchangeable lens camera having a TTL phase difference AF detection device via an intermediate adapter, high-precision AF is achieved. An object of the present invention is to provide an interchangeable lens camera and a camera system.

That is, the camera system according to the first aspect of the present invention includes a camera body, a photographing lens, an interchangeable lens that can be attached to and detached from the camera body, and an intermediate that can be mounted between the interchangeable lens and the camera body. An interchangeable lens, which is determined based on the optical characteristics of the photographing lens and is AF correction data having a configuration corresponding to the type of light source that illuminates the subject, A first AF correction data storage unit storing first AF correction data to be applied when the adapter is not mounted, and AF correction data to be applied when the intermediate adapter is mounted. A second AF correction data storage unit in which certain second AF correction data is stored, and the intermediate adapter includes the second AF correction data. A correction coefficient storage unit that stores a correction coefficient for correction, and the camera body includes a light source detection unit that detects a light source that illuminates the subject, a mounting determination unit that determines whether the intermediate adapter is mounted, An adapter determination unit that determines whether or not the intermediate adapter is an intermediate adapter to which the second AF correction data can be applied when the mounting determination unit determines that the intermediate adapter is mounted; When the adapter determination unit determines that the intermediate adapter is not an intermediate adapter to which the second AF correction data can be applied, the correction coefficient stored in the correction coefficient storage unit of the intermediate adapter is used. A correction unit that corrects the second AF correction data, a focus detection unit that detects a defocus amount when the interchangeable lens is mounted, and the adapter detection unit. When the intermediate adapter determines that the intermediate adapter is not an intermediate adapter to which the second AF correction data is applicable, the defocus amount detected by the focus detection unit is detected by the light source detection unit. And a defocus amount correction unit that corrects using the second AF correction data corrected by the correction unit based on the result .

A camera according to a second aspect of the present invention is a camera in which an interchangeable lens including a photographing lens is detachable via an intermediate adapter, and a mounting determination unit that determines whether the intermediate adapter is mounted, When the determination unit determines that the intermediate adapter is attached, the intermediate adapter is determined based on the optical characteristics of the photographing lens stored in the storage unit in the interchangeable lens and illuminates the subject. An adapter determination unit that determines whether or not the AF correction data having a configuration corresponding to the type of light source is applicable, and the adapter determination unit allows the intermediate adapter to apply the AF correction data. A correction unit that corrects the AF correction data using a correction coefficient stored in the intermediate adapter when it is determined that the adapter is not an intermediate adapter; When the intermediate detection adapter determines that the intermediate adapter is not an intermediate adapter to which the AF correction data can be applied by the focus detection unit that detects the amount of defocus when the interchangeable lens is mounted and the adapter determination unit. The defocus amount correction for correcting the defocus amount detected by the focus detection unit using the second AF correction data corrected by the correction unit based on the detection result by the light source detection unit. And a portion .

An interchangeable lens according to a third aspect of the present invention is an interchangeable lens that can be attached to and detached from the camera body via an intermediate adapter, and is determined based on the optical characteristics of the photographing lens and is a light source that illuminates a subject. A first AF correction data storage unit storing first AF correction data to be applied when the intermediate adapter is not mounted, the AF correction data having a configuration corresponding to the type; A second AF correction data storage unit storing second AF correction data, which is AF correction data applied when the intermediate adapter is attached, and the second AF correction. If the data for use does not correspond to the intermediate adapter attached to the interchangeable lens, the second AF correction data is stored in the correction coefficient storage unit of the intermediate adapter. Are corrected using, characterized in that it is applied to an intermediate adapter that is the mounting.

  According to the present invention, even when an interchangeable lens is attached to an interchangeable lens camera having a TTL phase difference AF detection device via an intermediate adapter, high-precision AF is possible.

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

(First embodiment)
FIG. 1 is a block diagram showing a basic configuration of a camera system of the present invention.

  In FIG. 1, the camera system includes an interchangeable lens unit 10, an intermediate adapter 20, and a camera body unit 30. The interchangeable lens unit 10, the intermediate adapter 20, and the camera body unit 30 are configured to be detachable from each other by a mount mechanism (not shown).

  The interchangeable lens unit 10 includes photographing lenses 11 a and 11 b, a diaphragm 12, a lens driving mechanism 13, a diaphragm driving mechanism 14, a lens CPU 15, and a data storage unit 16.

  The lens CPU 15 controls the interchangeable lens unit 10 in an integrated manner. That is, a control signal is output to the lens driving mechanism 13 to move the positions of the photographing lenses 11a and 11b back and forth for the focusing operation. Further, a control signal is output to the aperture driving mechanism 14 to change the aperture position of the aperture 12 for exposure control. Further, the lens CPU 15 receives various information by exchanging signals with the camera body unit 30.

  The data storage unit 16 is a storage unit (first storage unit, first storage unit) that stores lens-specific information (for example, lens focal length, open F value, AF correction data, etc.). These lens-specific information is read by the lens CPU 15 serving as a reading unit and a camera CPU 35 described later.

  The intermediate adapter 20 includes a teleconversion lens 21, an adapter CPU 22, and an adapter storage unit (second storage unit, second storage unit) 23.

  The tele conversion lens 21 is for changing the focal length of the interchangeable lens unit 10 described above. The teleconversion lens 21 can enlarge the magnification of the lens, for example, twice.

  The adapter storage unit 23 stores information unique to the intermediate adapter (for example, lens type, AF correction data, etc.). The adapter CPU 22 sends and receives signals to and from the camera body unit 30 described above, and transmits information specific to the intermediate adapter for AF correction.

  The camera body unit 30 includes a quick return mirror 31, a shutter 32, an image sensor 33, an image processing circuit 34, a camera CPU 35, an image monitor 36, an image memory 37, a camera storage unit 39, and a focusing screen. 40, a pentaprism 41, a photometry circuit 42, an auxiliary light unit 43, a sub mirror 44, an AF lens 45, an AF sensor 46, a distance measuring unit 47, a shutter drive mechanism 48, and a mirror drive mechanism 49. , A diffusion plate 50, a light source sensor 51, and a light source detection circuit 52.

  The quick return mirror 31 is a half mirror at the center, and guides the subject image to the pentaprism 41 and the AF sensor 46 during non-shooting operation.

  The image sensor 33 converts an optical image of a subject into image data that is an electrical signal using, for example, a CCD. The camera CPU 35 comprehensively controls the operation of the camera system and controls the image processing circuit 34 to perform various image processing on the image data. Information necessary for the operation of the camera CPU 35 is stored in the camera storage unit 39.

Further, the camera CPU 35 acquires lens characteristic information of the photographing lenses 11a and 11b and information specific to the intermediate adapter for AF correction through communication with the lens CPU 15 in the interchangeable lens unit 10 and the adapter CPU 22 in the intermediate adapter 20. . The camera CPU 35 constitutes a reading unit, a selection unit, a correction unit, and a determination unit (adapter determination unit, adapter mounting determination unit) .
“ASEL”, “LSEL”, “DATA”, and “CONT” are provided on signal lines for information exchange of the camera CPU 35. “ASEL” is a line for selecting information communication with the intermediate adapter 20. “LSEL” is a line for selecting information communication with the interchangeable lens unit 10. “DATA” is a common line for communicating lens specific information and the like. Further, “CONT” is a control signal line for communicating a control command (for example, a lens information request, an aperture drive command, etc.).

  The image monitor 36 is composed of a liquid crystal monitor or the like, and displays image data. The image memory 37 is for recording image data which is a recording medium such as SmartMedia (registered trademark).

  The focusing screen 40 is for focusing the subject light image reflected upward by the quick return mirror 31.

  The photometry circuit 42 receives a part of the subject light image from the pentaprism 41 by a photoelectric conversion element (not shown) and measures the luminance of the subject. The camera CPU 35 calculates the exposure condition based on the measurement data of the photometry circuit 42.

Auxiliary light unit 43 is an auxiliary light publicly known use is controlled by the camera CPU 35. The auxiliary light from the auxiliary light unit 43 illuminates the subject by emitting a red light emitting diode (not shown) in the auxiliary light unit 43 in synchronization with the integration operation of the AF sensor 46 when the subject has low brightness. It is like that. The spectral characteristics of the red light emitting diode are shown in FIG. 3 (details will be described later).

  The sub mirror 44 is attached to the quick return mirror 31 so as to be foldable. The sub mirror 44 guides a light beam that passes through a part of the quick return mirror 31 to the AF sensor 46 side when the quick return mirror 31 is disposed on the optical axis of the photographing lenses 11a and 11b. is there.

  The AF sensor 46 is a focus detection unit that receives the subject light image divided into two by the sub mirror 44 through the AF lens 45. The distance measuring unit 47 calculates a lens driving amount for focusing based on the output of the AF sensor 46. This AF distance measuring mechanism is based on a so-called TTL phase difference method, and the light beam used for focus detection is a light beam corresponding to the case where the aperture of the photographing lens is reduced to about F8.

  FIG. 2 schematically shows a detection area of the AF sensor 46 that constitutes a part of the focus detection device in the camera system of the present embodiment, and a detection area of the light source sensor 51 that is a light source detection means. The relationship between the detection area and the shooting screen (shooting angle of view) 55 is shown.

  In FIG. 2, a region 56 (a region indicated by hatching in FIG. 2) indicates a detection area of the AF sensor 46. Similarly, regions 57a and 57b indicate detection areas of the light source sensor 51.

  Next, how the AF sensor 46 and the distance measurement unit 47 affect the distance measurement result depending on the type of light source that illuminates the subject will be described.

  First, the wavelength characteristics of the light source will be described.

  FIG. 3 is a schematic diagram illustrating spectral characteristics of various illumination light sources that illuminate a subject. Illustrative examples of the illumination light source include A: fluorescent lamp, B: daylight, C: incandescent bulb, D: blue flood lamp, E: auxiliary light.

  As shown in FIG. 3, the spectral characteristics of the fluorescent lamp are in the range from about 300 nm to about 800 nm with the vicinity of about 500 nm as a vertex. Further, the spectral characteristics of the incandescent lamp are in a region closer to a longer wavelength than the vicinity of about 300 nm with the vicinity of about 1000 nm as the apex. The spectral characteristics of the blue flood lamp have a steep sensitivity in the vicinity of about 800 nm and are in a region from about 300 nm to about 850 nm. Further, the spectral characteristics of general natural light (daylight) have spectral characteristics over a relatively entire range from a region closer to a longer wavelength than approximately 300 nm. The spectral characteristic of the auxiliary light has a steep sensitivity around about 700 nm.

  FIG. 4 is a diagram illustrating a state in which a gap between two images formed on the light receiving unit of the AF sensor 46 is shifted depending on the type of light source that illuminates the subject.

  For example, assuming that the interval between two images is focused in daylight, and the same subject is illuminated with a blue flood lamp and photographed, the following occurs. That is, as shown in FIG. 4, it can be seen that a deviation of about +0.2 pixels occurs on the light receiving surface of the AF sensor 46 as compared with the in-focus state in daylight. This is because the optical components of the photographic lens and the AF optical system are different when the wavelength component of the AF detection light beam is different. Since this is disclosed in Japanese Patent No. 2666274, description thereof is omitted here.

  The above approximately +0.2 pixel corresponds to, for example, +0.1 mm in terms of the focus position. The distance measuring sensor has a line sensor and means the pixel.

  In this way, when the in-focus position is shifted by the illumination light source, a so-called out-of-focus photograph is generated, which becomes a problem. Therefore, in the present invention, the type of the light source is determined by the light source sensor 51, and the AF stored in the data storage unit 16 in the interchangeable lens unit 10, the adapter storage unit 23 in the intermediate adapter 20 or the like accordingly. The above problem is solved by using correction values and correction coefficients.

  The light source sensor 51 described above is a light source detection unit configured by an external light sensor in the present embodiment, and detects subject light that has not passed through the interchangeable lens unit 10 via the diffusion plate 50. The light source sensor 51 includes a visible light sensor 69 and an infrared light sensor 68 (see FIG. 7, both of which will be described in detail later). Since the subject light is incident through the diffusion plate 50, The field of view of the sensor is the same and has a wide angle of view.

  The visible light sensor 69 correctly has visible and near infrared spectral sensitivities, but an infrared cut filter 70 (see FIG. 7; details will be described later) between the visible light difference 69 and the diffuser plate 50. ) Is inserted, and finally only visible light is received. The light source sensor 51 compresses the photocurrent corresponding to each spectral sensitivity sensor, converts the current to voltage, and outputs the result. The output of the light source detection sensor is A / D converted by the light source detection circuit 52 so that the brightness of the entire subject according to the spectral sensitivity of each sensor can be detected.

  Next, the principle of detecting the type of light source will be described.

  FIG. 5 is a diagram for measuring illumination light for illuminating a subject in the camera system of the present embodiment. The spectral sensitivity characteristic of a visible light sensor 69 described later and the spectral sensitivity characteristic of an infrared light sensor 68 described later are respectively shown. FIG.

The spectral sensitivity characteristic of the visible light sensor 69 in the camera system of the present embodiment is as shown by the symbol F in FIG. 5. The spectral sensitivity near the short wavelength region with the peak at about 500 nm (peak: maximum value). It has characteristics and has sensitivity in the visible light region. In addition, the spectral sensitivity characteristic of the infrared light sensor 68 in the camera has a spectral sensitivity characteristic up to a long wavelength region near 1000 nm with the peak at around 700 nm as indicated by the symbol G in FIG. ing.

In the following description, photometry by the visible light sensor 69 is referred to as visible photometry, and photometry by the infrared light sensor 68 is referred to as infrared photometry.

  FIG. 6 is a diagram showing the difference (ΔBV) between infrared photometry and visible photometry using the above-mentioned light source, normalized using a tungsten lamp (incandescent lamp) as a reference, and the light source determination method in the present embodiment. FIG.

  In FIG. 6, since the reference light source is a tungsten lamp, the brightness difference ΔBV is 0.0 for tungsten lamp, −1.1 for sunlight, −7.1 for white fluorescent lamp, and 3 wave daylight. -7.5 for white fluorescent lamps, -6.2 for daylight white fluorescent lamps, -7.5 for 3-wave daylight fluorescent lamps, and +1.3 for blue flood lamps. Here, “standardized with a tungsten lamp” is a value obtained by subtracting the luminance difference when the camera is irradiated with the tungsten lamp from the luminance difference when the camera is irradiated with each light source light.

  Here, for example, in the case where threshold values are provided at positions where the luminance difference is −3 and +0.5, when the value of the luminance difference ΔBV exceeds −3, it is determined that the lamp is a fluorescent lamp. It can be determined as a lamp.

  FIG. 7 is a diagram showing the arrangement of the light source sensor 51, and FIG. 8 is a plan view showing the configuration of the light source sensor 51.

The light source sensor 51 is disposed behind the diffusion plate 50 inside the camera exterior 65 of the camera body unit 30. The light source sensor 51 has a configuration in which an infrared sensor 68 and a visible light sensor (SPD) 69 and a control IC 72 for controlling these sensors are mounted on a clear mold 66. Further, the front portion of the visible light sensor 69, i.e., on the side facing the diffuser plate 50, the infrared cut filter 70 is arranged. The infrared cut filter 70, the infrared light is cut, the visible light sensor 69 becomes the visible light sensor having a spectral sensitivity close to the visible light.

  In this embodiment, in order to perform visible photometry, a sensor having spectral sensitivity in the infrared visible region and an infrared cut filter are combined. In the case of such a configuration, light that is incident on the sensor without being cut by infrared rays is generated depending on the position of the infrared cut filter. Since this amount varies depending on the assembly error of the camera and the like, the absolute amount of the luminance difference between visible light and infrared light when the light from each light source is irradiated on the camera is different.

  However, the value obtained by standardizing the luminance difference based on the reference light source (in this embodiment, tungsten light) is constant regardless of the individual camera difference. Therefore, the light source can be determined stably based on the principle shown in FIG.

  Next, the operation of the camera system configured as described above will be described.

When a release button (not shown) of the camera body unit 30 is pushed in one step by the photographer, the camera CPU 35 calculates an aperture value for obtaining an appropriate exposure based on the subject luminance data measured by the photometry circuit 42. The result is transmitted to the lens CPU 15. The lens CPU 15 outputs a signal to the aperture driving mechanism 14 so as to obtain a desired aperture.

  Further, the camera CPU 35 performs processing such as AF correction based on the detection result of the distance measuring unit 47, the lens information of the interchangeable lens unit 10 and the lens information of the intermediate adapter 20 that are received in advance for focusing. The driving amounts of the photographing lenses 11 a and 11 b are calculated and transmitted to the lens CPU 15. In the lens CPU 15, a control signal for moving the photographing lenses 11 a and 11 b to the in-focus position is output to the lens driving mechanism 13 based on this driving amount.

  When the photographer pushes a release button (not shown) of the camera body unit 30 in two stages, the camera CPU 35 retracts the quick return mirror 31 out of the photographing optical path. Thereafter, the shutter 32 is operated to guide the light image of the subject to the image sensor 33, and image processing is performed on the image data obtained from the image sensor 33.

  Next, variations of the configuration of the camera system in the first embodiment will be described.

  The camera system according to the present invention may be configured as the following three variations including the configuration shown in FIG. 1 (the configuration including the above-described interchangeable lens unit 10, the intermediate adapter 20, and the camera body unit 30). it can.

  In the following description of the embodiments and variations, since they are basically the same as those shown in FIGS. 1 to 8, the same reference numerals are given to the same parts, and the illustrations and explanations are given. Are omitted, and only different parts will be described.

  FIG. 9 is a diagram showing the configuration of the first variation of the camera system according to the present invention. In the first variation, the camera system includes an interchangeable lens unit 10 and a camera body unit 30.

  The data storage unit 16 stores AF correction data (ΔAFD0) 16a when there is no intermediate adapter 20 and AF correction data (ΔAFD1) 16b when there is an intermediate adapter 20 as AF correction data.

  Then, the camera CPU 35 corrects the distance measurement output (AFD), for example, by the TTL phase difference method from the distance measurement unit 47 using the AF correction data, and transmits the focus adjustment drive amount of the photographing lens to the lens CPU 15. .

  Here, the configuration of the AF correction data will be described.

Table 1 below shows the configuration of the AF correction data ΔAFD0 stored in the data storage unit 16 in the interchangeable lens unit 10 in advance.

AF correction data is stored corresponding to the focal lengths 1 to n of the interchangeable lens unit 10 and further corresponding to the type of light source. The AF correction data includes, for example, fluorescent lamp fluo _0n , daylight sun _0n , incandescent lamp infr _0n , blue flood lamp bru _0n , and auxiliary light hojo _0n . These data are read from the data storage unit 16 and stored in the camera storage unit 39 of the camera body unit 30 by communication between the camera CPU 35 in the camera body unit 30 and the lens CPU 15 in the interchangeable lens unit 10.

Similarly, the data storage unit 16 in the interchangeable lens unit 10 also stores AF correction data ΔAFD1. Table 2 below shows the configuration of the AF correction data ΔAFD1 stored in advance in the data storage unit 16 in the interchangeable lens unit 10.

  The data configuration is the same as the AF correction data ΔAFD0 in Table 1 above.

Further, the correction coefficient α stored in the adapter storage unit 23 in the intermediate adapter (B type) 20b shown in FIG. 11 is configured as shown in Table 3 below.

  If the interchangeable lens unit 10 is not composed of a zoom lens, only the data corresponding to the focal length 1 is stored.

  FIG. 10 is a diagram showing the configuration of the second variation of the camera system according to the present invention. In the second variation, the camera system includes an interchangeable lens unit 10, an A-type intermediate adapter 20a, and a camera body unit 30. Here, the A-type intermediate adapter 20a means an initial version of the intermediate adapter.

  The data storage unit 16 stores AF correction data (ΔAFD0) 16a when there is no intermediate adapter 20 and AF correction data (ΔAFD1) 16b when there is an A-type intermediate adapter 20a as AF correction data. Yes. Although the adapter CPU 22 is provided in the A-type intermediate adapter 20a, the adapter storage unit 23 is not particularly required. Even if provided, data relating to AF correction is not stored.

  Then, the camera CPU 35 corrects, for example, a distance measurement output (AFD) by the TTL phase difference method from the distance measurement unit 47 using AF correction data, and transmits the focus adjustment drive amount of the photographing lens to the lens CPU 15. To do.

  FIG. 11 is a diagram showing the configuration of the third variation of the camera system according to the present invention. In the third variation, the camera system includes an interchangeable lens unit 10, a B-type intermediate adapter 20b, and a camera body unit 30. Here, the B-type intermediate adapter 20b means an upgraded product obtained by improving the A-type intermediate adapter 20a.

  The data storage unit 16 stores AF correction data (ΔAFD0) 16a when there is no intermediate adapter 20 and AF correction data (ΔAFD1) 16b when there is an A-type intermediate adapter 20a as AF correction data. Yes. The B-type intermediate adapter 20b is provided with an adapter storage unit 23 together with the adapter CPU 22 for converting AF correction data for the A-type intermediate adapter 20a into AF correction data for the B-type intermediate adapter 20b. A correction coefficient α is stored.

  Then, the camera CPU 35 corrects the distance measurement output (AFD) from the distance measurement unit 47 using, for example, a TTL phase difference method using these AF correction data, and adjusts the focus adjustment drive amount of the photographing lens to the lens CPU 15. Send to.

  Next, the AF correction operation of the camera system will be described.

  The operation related to the AF correction of the camera system is roughly divided into the following two.

(1) An operation in which the camera CPU 35 in the camera body unit 30 acquires lens information from the interchangeable lens unit 10 and the intermediate adapter 20.
(2) An operation in which the camera CPU 35 in the camera body unit 30 calculates a defocus correction amount for focusing.

  Hereinafter, these operations will be described. The camera CPU 35 has a processing function that can cope with variations of the above-described three configurations (see FIGS. 9 to 11).

  FIG. 12 is a schematic flowchart showing a procedure by which the camera CPU 35 acquires lens information. This flowchart is started when the power of the camera body unit 30 is turned on or when the interchangeable lens unit 10 and the intermediate adapter 20 are attached.

  First, in step S <b> 1, a lens selection signal is output from the camera CPU 35 in order to receive lens information from the interchangeable lens unit 10. That is, the signal level of the “LSEL” line is changed from Low (low level) to High (high level). Next, in step S2, whether or not there is a response from the interchangeable lens unit 10 is determined.

  If communication is possible, the lens CPU 15 returns a response signal indicating that the communication is ready. If there is no response from the interchangeable lens unit 10, the processing of the camera CPU 35 ends. On the other hand, if there is a response from the interchangeable lens unit 10, the process proceeds to step S <b> 3 and lens information is requested by the camera CPU 35. That is, a lens information request command is set in the “CONT” line.

  In response to this request signal, the lens CPU 15 searches the data storage unit 16 to extract lens information. The extracted lens information is transmitted from the lens CPU 15 to the camera CPU 35. The transmitted lens information is, for example, the lens type, open FNo, focal length, focus lens position, AF correction data (ΔAFD0, ΔAFD1), and the like.

  In step S 4, the lens information to be transmitted is read by the camera CPU 35 and stored in the camera storage unit 39. Subsequently, in step S5, an adapter selection signal is output by the camera CPU 35 in order to receive adapter information from the intermediate adapter 20. That is, the signal level of the “ASEL” line is changed from Low to High.

  In step S6, the presence / absence of a response from the intermediate adapter 20 is determined. If the communication is possible, the adapter CPU 22 returns a response signal indicating that the communication is ready to the camera CPU 35.

  When there is no response from the intermediate adapter 20, the camera system is configured as shown in FIG. 9, and the processing by the camera CPU 35 is completed. On the other hand, when there is a response from the intermediate adapter 20, the response is checked by the camera CPU 35, and the type of the intermediate adapter attached to the camera body unit 30 is determined.

  Next, the process proceeds to step S8, and it is determined whether or not the type of the intermediate adapter attached to the camera body unit 30 is a B-type intermediate adapter. Here, when it is not the B-type intermediate adapter, that is, in the case of the A-type intermediate adapter, the camera system is configured as shown in FIG. Therefore, since the lens correction data (ΔAFD1) has already been acquired by the camera CPU 35, the processing is terminated.

  On the other hand, if the type of the intermediate adapter to be attached is the B-type intermediate adapter in step S8, the camera system is configured as shown in FIG. 11, and adapter information is requested by the camera CPU 35. That is, an adapter information request command is set in the “CONT” line. In response to this request signal, the adapter CPU 22 searches the adapter storage unit 23 and extracts adapter information. Then, the extracted adapter information is transmitted to the camera CPU 35. The adapter information to be transmitted is, for example, the correction coefficient α described above.

  In step S <b> 9, the transmitted adapter information is read by the camera CPU 35 and stored in the camera storage unit 39.

  Through the above procedure, the camera CPU 35 acquires AF correction data corresponding to the above-described variations 1 to 3 of the configuration and stores the data in the camera storage unit 39.

  FIG. 13 is a schematic flowchart showing a procedure in which the camera CPU 35 performs a correction operation of the defocus amount for focusing. This flowchart represents an AF operation for preparing for photographing, which is executed when a photographer presses a release button (not shown) of the camera body unit 30.

  First, in step S11, the light source sensor 51 is operated by the camera CPU 35, and the subroutine “light source detection” is executed.

  Here, the detailed operation of the subroutine “light source detection” in step S11 in the flowchart of FIG. 13 will be described with reference to the flowchart of FIG.

  When entering this routine, first, flags F_FLUO, F_SUN, F_INFR, F_BRUF, and F_HOJO representing the type of light source (not shown) are cleared. Next, in step S31, it is determined whether or not auxiliary light is emitted during the integration operation of the AF sensor 46. Here, when the auxiliary light is emitted, the process proceeds to step S46, and 1 is set to the flag [F_HOJO]. Thereafter, the routine is exited.

  On the other hand, if the auxiliary light is not emitted in step S31, the process proceeds to step S32, and the output of the light source sensor 51 is read. Next, the luminance of the light source is calculated from the output of the light source sensor 51 in step S33. Further, in step S34, the luminance values of visible light and infrared light are respectively calculated.

In step S35, the difference between visible light (BV_eye) and infrared light (BV_ir) is calculated according to the following equation.
D_BV ← BV_ir-BV_eye
D_BV ← D_BV-DBV_REF
Here, DBV_REF is a luminance difference between visible light and infrared light at the time of reference tungsten light (incandescent lamp) irradiation, and is stored as an adjustment value in the camera CPU 35 as a different value depending on the individual camera.

  In this way, the calculated difference is normalized based on tungsten light (incandescent lamp).

  Next, in step S36, it is determined whether or not the above-described luminance value of visible light is a usable value. This is because when the luminance is too bright or too dark, the light source detection accuracy of the light source sensor deteriorates, and the output of the light source detection is not very reliable. In this case, in step S36, it is determined whether the luminance value of visible light is less than −2 or greater than 8.

  Here, if the luminance value of the visible light is smaller than −2 or larger than 8, the process proceeds to step S45 and the light source is unknown. On the other hand, if the luminance value is −2 or more and 8 or less, the process proceeds to step S37.

  In step S37, the luminance difference D_BV calculated in step S35 is compared with the fluorescent lamp threshold value BV_TH_kei. If the brightness difference D_BV is smaller than the fluorescent lamp threshold BV_TH_kei, the process proceeds to step S41, and if greater, the process proceeds to step S38.

  In step S38, it is determined whether or not the luminance difference D_BV calculated in step S35 is between the fluorescent lamp threshold BV_TH_kei and the sunlight threshold BV_TH_sun. Here, if the luminance difference D_BV is within the range of both thresholds, the process proceeds to step S42, and if it is outside the range of both thresholds, the process proceeds to step S39.

  In step S39, it is determined whether the luminance difference D_BV calculated in step S35 is between the sunlight threshold BV_TH_sun and the tungsten light threshold BV_TH_fl. Here, if the luminance difference D_BV is within the range of both threshold values, the process proceeds to step S43, and if it is outside the range of both threshold values, the process proceeds to step S40.

  In step S40, the brightness difference D_BV calculated in step S35 is compared with the tungsten light threshold value BV_TH_fl. If the luminance difference D_BV is larger than the tungsten light threshold BV_TH_fl, the process proceeds to step S44, and if smaller, the process proceeds to step S45.

As shown in Table 4 below, the threshold value of each light source described above is set such that, for example, the fluorescent lamp threshold BV_TH_kei is −3, the sunlight threshold BV_TH_sun is −0.5, and the tungsten light threshold BV_TH_fl is +0.5. Is done.

In step S41, the light source is regarded as a fluorescent lamp (1 is set in the flag [F_FLUO]). Similarly, in step S42, the light source is regarded as sunlight, and in step S43, the light source is regarded as tungsten light. Further, in step S44, the light source is regarded as a blue flood lamp. In step S45 , as described above, the light source is unknown. When the light source is unknown, the flag [F_FLUO] is set because the correction value of the fluorescent lamp that is the reference light source when adjusting the in-lens defocus correction value is used.

  When the light source is thus detected, the routine is exited.

Returning to the flowchart of FIG. 13, in step S <b> 12, the camera CPU 35 outputs an instruction to start the operation to the AF sensor 46 . In subsequent step S13, it is determined from the output of the photometry circuit 42 whether or not the subject has low luminance. As a result, if the subject has low luminance, the process proceeds to step S14, and the auxiliary light unit 43 emits light in synchronization with the integration operation of the AF sensor 46. If the brightness is not low in step S13, step S14 is skipped.

  In step S15, AF sensor data is fetched from the AF sensor 46. Next, in step S16, the distance measuring unit 47 obtains the number of shift pitches on the sensor from the AF sensor data, and further calculates the defocus amount (AFD) of the photographing lenses 11a and 11b from the pitch number.

  Next, in step S17, it is determined whether or not the intermediate adapter 20 is connected. Here, when the intermediate adapter 20 is not connected, the camera system has a configuration shown in FIG. Therefore, the process proceeds to step S23, and the AF correction data (ΔAFD0) 16a when the intermediate adapter 20 is not connected to the defocus amount (AFD) from the distance measuring unit 47 is based on the light source detection result. Then, the type of the light source is determined, data is selected, and ΔAFD0S is set.

  Here, the operation of the subroutine “light source determination, AF correction value (ΔAFD0S) selection” in step S23 in the flowchart of FIG. 13 will be described with reference to the flowchart of FIG.

  When entering this subroutine, first in step S51, the focal length information n communicated from the lens CPU 15 is input to m. Next, in step S52, it is determined whether or not a flag [F_HOJO] representing auxiliary light is set. If the flag [F_HOJO] is set here, the process proceeds to step S53. In step S53, hojo0m is selected and input as the AF correction value ΔAFD0S based on Table 1 above. Thereafter, the routine is exited.

  If the flag [F_HOJO] is not set in step S52, the process proceeds to step S54. In step S54, it is determined whether or not a flag [F_BRUF] representing a blue flood lamp has been set. Here, when the flag [F_BRUF] is set, the process proceeds to step S55. In step S55, bruf0m is selected and input as the AF correction value ΔAFD0S based on Table 1 above. Thereafter, the routine is exited.

  On the other hand, if the flag [F_BRUF] is not set in step S54, the process proceeds to step S56. In step S56, it is determined whether or not a flag [F_INFR] representing an incandescent lamp has been set. If the flag [F_INFR] is set here, the process proceeds to step S57. In step S57, infr0m is selected and input as the AF correction value ΔAFD0S based on Table 1 above. Thereafter, the routine is exited.

  If the flag [F_INFR] is not set in step S56, the process proceeds to step S58. In step S58, it is determined whether or not a flag [F_FLUO] representing a fluorescent lamp has been set. If the flag [F_FLUO] is set, the process proceeds to step S59. In step S59, fluo0m is selected and inputted as the AF correction value ΔAFD0S based on Table 1 above. Thereafter, the routine is exited.

  If the flag [F_FLUO] is not set in step S58, the process proceeds to step S60, and sun0m is selected and input to the AF correction value ΔAFD0S based on Table 1 above. Thereafter, the routine is exited.

  Returning to the flowchart of FIG. 13, in step S24, ΔAFD0S is added to the defocus amount (AFD) to calculate the corrected defocus amount (AFD ′).

  If the intermediate adapter 20 is connected in step S17, the process proceeds to step S18, and AF correction data (ΔAFD1) 16b when the intermediate adapter 20 is present is extracted from the camera storage unit 39. Light source determination is performed, and data is selected to be ΔAFD1S.

Here, the operation of the subroutine “light source determination, AF correction value (ΔAFD 1S ) selection” in step S18 in the flowchart of FIG. 13 will be described with reference to the flowchart of FIG.

  When entering this subroutine, first in step S71, the focal length information n communicated from the lens CPU 15 is input to m. Next, in step S72, it is determined whether or not a flag [F_HOJO] representing auxiliary light is set. If the flag [F_HOJO] is set here, the process proceeds to step S73. In step S73, hojo1m is selected and input to the AF correction value ΔAFD1S based on Table 2 above. Thereafter, the routine is exited.

  If the flag [F_HOJO] is not set in step S72, the process proceeds to step S74. In step S74, it is determined whether or not a flag [F_BRUF] representing a blue flood lamp has been set. If the flag [F_BRUF] is set, the process proceeds to step S75. In step S75, bruf1m is selected and inputted as the AF correction value ΔAFD1S based on Table 2 above. Thereafter, the routine is exited.

  On the other hand, if the flag [F_BRUF] is not set in step S74, the process proceeds to step S76. In step S76, it is determined whether or not a flag [F_INFR] indicating an incandescent lamp is set. If the flag [F_INFR] is set here, the process proceeds to step S77. In step S77, infr1m is selected and input as the AF correction value ΔAFD1S based on Table 2 above. Thereafter, the routine is exited.

  If the flag [F_INFR] is not set in step S76, the process proceeds to step S78. In step S78, it is determined whether or not a flag [F_FLUO] representing a fluorescent lamp has been set. If the flag [F_FLUO] is set, the process proceeds to step S79. In step S79, fluo1m is selected and input as the AF correction value ΔAFD1S based on Table 2 above. Thereafter, the routine is exited.

  If the flag [F_FLUO] is not set in step S78, the process proceeds to step S80, and sun1m is selected and input to the AF correction value ΔAFD1S based on Table 2 above. Thereafter, the routine is exited.

  Returning to the flowchart of FIG. 13, in step S19, the camera storage unit 39 is searched to determine the type of the intermediate adapter, and it is checked whether or not the type of the intermediate adapter is a B-type intermediate adapter. Here, if it is not the B-type intermediate adapter, that is, if it is the A-type intermediate adapter, the camera system has the configuration shown in FIG. 10, and the camera CPU 35 has already acquired the AF correction data (ΔAFD1) 16b. . Accordingly, the process proceeds to step S20, and the camera CPU 35 adds the AF correction data (ΔAFD1S) 16b when the intermediate adapter 20 is present to the defocus amount (AFD) from the distance measuring unit 47 to correct the amount. A defocus amount (AFD ′) is calculated. Thereafter, the routine is exited.

On the other hand, if it is determined in step S19 that it is a B-type intermediate adapter, the camera system has the configuration shown in FIG. Therefore, the process proceeds to step S21, where the camera CPU 35 extracts the correction coefficient α from the camera storage unit 39, performs light source determination, and selects data to be α _S.

Here, the operation of the subroutine “light source determination, correction coefficient (α _S ) selection” in step S21 in the flowchart of FIG. 13 will be described with reference to the flowchart of FIG.

When entering this subroutine, first in step S91, the focal length information n communicated from the lens CPU 15 is input to m. Next, in step S92, it is determined whether or not a flag [F_HOJO] representing auxiliary light is set. If the flag [F_HOJO] is set, the process proceeds to step S93. In step S93, α _hm is selected and input as the correction coefficient α _S based on Table 3 above. Thereafter, the routine is exited.

If the flag [F_HOJO] is not set in step S92, the process proceeds to step S94. In step S94, it is determined whether or not a flag [F_BRUF] representing a blue flood lamp has been set. If the flag [F_BRUF] is set, the process proceeds to step S95. In step S95, α _bm is selected and input as the correction coefficient α _S based on Table 3 above. Thereafter, the routine is exited.

On the other hand, if the flag [F_BRUF] is not set in step S94, the process proceeds to step S96. In step S96, it is determined whether or not a flag [F_INFR] indicating an incandescent lamp is set. If the flag [F_INFR] is set here, the process proceeds to step S97. In step S97, α _im is selected and input as the correction coefficient α _S based on Table 3 above. Thereafter, the routine is exited.

If the flag [F_INFR] is not set in step S96, the process proceeds to step S98. In step S98, it is determined whether or not a flag [F_FLUO] representing a fluorescent lamp has been set. If the flag [F_FLUO] is set here, the process proceeds to step S99. In step S99, α _fm is selected and input as the correction coefficient α _S based on Table 3 above. Thereafter, the routine is exited.

If the flag [F_FLUO] is not set in step S98, the process proceeds to step S100, and α _sm is selected and input to the correction coefficient α _S based on Table 3 above. Thereafter, the routine is exited.

Returning to the flowchart of FIG. 13, in step S22, the AF correction data (ΔAFD1S) 16b when the intermediate adapter 20 is present is multiplied by the correction coefficient α _S with respect to the defocus amount (AFD) from the distance measuring unit 47. The corrected values are added to calculate the corrected defocus amount (AFD ′).

  Then, the camera CPU 35 transmits the corrected defocus amount (AFD ′) calculated in the above procedure to the lens CPU 15. The lens CPU 15 moves the photographing lenses 11a and 11b based on this value to perform a focusing operation.

Incidentally, in step S 22, but AF correction data (ΔAFD1S) correction defocus amount is multiplied by the correction coefficient alpha _S to 16b (AFD ') are calculated, but is not limited to this embodiment . For example, the correction coefficient α _S may be added (subtracted) to the AF correction data (ΔAFD1S) 16b, and a function having the AF correction data (ΔAFD1S) 16b and the correction coefficient α _S as parameters is used. A corrected defocus amount (AFD ′) may be calculated.

Further, in the camera CPU 35, the AF correction data (ΔAFD1S) 16b and the correction coefficient α _S are obtained from the interchangeable lens unit 10 and the intermediate adapter 20. The information may be received and an AF correction operation may be performed.

(Second Embodiment)
Next, a second embodiment of the present invention will be described.

  The second embodiment is an example in which correction by subject distance is further added according to the type of light source.

  It is known that the amount of focus deviation generated by the light source varies depending on the position of the focus lens. This is also known to be caused by the change in spherical aberration depending on the focus lens position, that is, the amount of extension of the focus lens (see FIG. 18).

  Since the focus lens position corresponds to the subject distance, the following description will be given with the same meaning.

Table 5 below shows focus deviation correction data corresponding to the light source stored in ΔAFD016a of the data storage unit 16 in the interchangeable lens barrel 10.

  This focus lens has, for example, a closest shooting distance of 0.5 m, and has a focus deviation correction data obtained by dividing a subject distance of 0.5 m to infinity into four areas.

  FIG. 18 shows the characteristics of only one type of light source, and the average defocus amount in each area is used as the correction data g.

  19 and 20 illustrate the operation of a subroutine “light source determination / AF correction value (ΔAFD0S) selection” for correcting the focus shift using the focus shift correction data in Table 5 in the second embodiment. It is a flowchart.

  Hereinafter, this operation will be described.

  The focus lens position (= distance) is detected by a focus encoder (not shown) in the lens driving mechanism 13 and is obtained from the lens CPU 15 through communication.

When the subroutine “light source determination / AF correction value selection” in step S23 in the flowchart of FIG. 13 is entered, first in step S111, the flag [F_HOJO] is determined. Here, when the flag [F_HOJO] is set, the process proceeds to step S112 to determine whether or not the subject distance L is 5 m or more. As a result, if the distance L is more than 5 m, the process proceeds to step S113, in accordance with correction data in Table 5, the aberration correction amount g _1H0 inputted to ΔAFD0S is data for AF correction. Then, this subroutine is exited.

On the other hand, the object distance L in step S112 is less than 5 m, the process proceeds to step S114, the subject distance L is equal to or between 2m~5m is determined. Here, if the between distance L is 2M～5m, the operation proceeds to Step S115, according to the correction data in Table 5, the aberration correction amount g _2H0 inputted to AF correction data DerutaAFD0S. Then, this subroutine is exited.

Furthermore, if the subject distance L is less than 2 m in step S114, the process proceeds to step S116 to determine whether or not the subject distance L is between 1 m and 2 m. Here, if the between distance L is 1 m to 2 m, the operation proceeds to step S117, the following correction data in Table 5, the aberration correction amount g _3H0 inputted to AF correction data DerutaAFD0S. Then, this subroutine is exited.

The distance L Te in step S116 is less than 1 m, the operation proceeds to step S118, the following correction data in Table 5, the aberration correction amount g _4H0 inputted to AF correction data DerutaAFD0S. Then, this subroutine is exited.

  On the other hand, if the flag [F_HOJO] is not set in step S111, the process proceeds to step S119, and it is determined whether or not the flag [F_BRUF] is set. If the flag [F_BRUF] is set, the process proceeds to step S120.

In step S120, it is determined whether or not the subject distance L is 5 m or more. As a result, if the distance L is more than 5 m, the process proceeds to step S121, in accordance with correction data in Table 5, the aberration correction amount g _1B0 is input to the AF correction data DerutaAFD0S. Then, this subroutine is exited.

On the other hand, if the subject distance L is less than 5 m in step S120, the process proceeds to step S122 to determine whether or not the subject distance L is between 2 m and 5 m. Here, if the between distance L is 2M～5m, the operation proceeds to step S123, in accordance with correction data in Table 5, the aberration correction amount g _2B0 is input to the AF correction data DerutaAFD0S. Then, this subroutine is exited.

Furthermore, if the subject distance L is less than 2 m in step S122, the process proceeds to step S124 to determine whether or not the subject distance L is between 1 m and 2 m. Here, if the between distance L is 1 m to 2 m, the operation proceeds to step S125, the following correction data in Table 5, the aberration correction amount g _3b0 is input to the AF correction data DerutaAFD0S. Then, this subroutine is exited.

If the subject distance L is less than 1 m in step S124, the process _proceeds to step S126, and the aberration correction amount g _4b0 is input to the AF correction data ΔAFD0S according to the correction data in Table 5. Then, this subroutine is exited.

  If the flag [F_BRUF] is not set in step S119, the process proceeds to step S127, and it is determined whether or not the flag [F_INFR] is set. If the flag [F_INFR] is set here, the process proceeds to step S129.

In step S129, it is determined whether or not the subject distance L is 5 m or more. As a result, if the distance L is more than 5 m, the process proceeds to step S130, in accordance with correction data in Table 5, the aberration correction amount g _1I0 are input to the AF correction data DerutaAFD0S. Then, this subroutine is exited.

On the other hand, if the subject distance L is less than 5 m in step S129, the process proceeds to step S131, and it is determined whether or not the subject distance L is between 2 m and 5 m. Here, if the between distance L is 2M～5m, the operation proceeds to Step S132, according to the correction data in Table 5, the aberration correction amount g _2I0 are input to the AF correction data DerutaAFD0S. Then, this subroutine is exited.

Furthermore, if the subject distance L is less than 2 m in step S131, the process proceeds to step S133, and it is determined whether or not the subject distance L is between 1 m and 2 m. If the subject distance L is between 1 m and 2 m, the process proceeds to step S134, and the aberration correction amount g _3i0 is input to the AF correction data ΔAFD0S according to the correction data in Table 5 above. Then, this subroutine is exited.

If the subject distance L is less than 1 m in step S133, the process proceeds to step S135, and the aberration correction amount g _4i0 is input to the AF correction data ΔAFD0S according to the correction data in Table 5 above. Then, this subroutine is exited.

  In step S127, if the flag [F_INFR] is not set, the process proceeds to step S128, and it is determined whether or not the flag [F_FLUO] is set. If the flag [F_FLUO] is set here, the process proceeds to step S136.

In step S136, it is determined whether or not the subject distance L is 5 m or more. As a result, if the subject distance L is 5 m or more, the _{process proceeds} to step S137, and the aberration correction amount g _1f0 is input to the AF correction data ΔAFD0S according to the correction data in Table 5 above. Then, this subroutine is exited.

On the other hand, if the subject distance L is less than 5 m in step S136, the process proceeds to step S138, and it is determined whether or not the subject distance L is between 2 m and 5 m. Here, if the between distance L is 2M～5m, the operation proceeds to Step S139, according to the correction data in Table 5, the aberration correction amount g _2f0 is input to the AF correction data DerutaAFD0S. Then, this subroutine is exited.

Further, if the subject distance L is less than 2 m in step S138, the process proceeds to step S140, and it is determined whether or not the subject distance L is between 1 m and 2 m. Here, if the between distance L is 1 m to 2 m, the process proceeds to step S141, in accordance with correction data in Table 5, the aberration correction amount g _3f0 is input to the AF correction data DerutaAFD0S. Then, this subroutine is exited.

The distance L Te in step S140 is less than 1 m, the process proceeds to step S142, in accordance with correction data in Table 5, the aberration correction amount g _4f0 is input to the AF correction data DerutaAFD0S. Then, this subroutine is exited.

  If the flag [F_FLUO] is not set in step S128, the process proceeds to step S143. In this case, since the auxiliary light, the blue flood lamp, the incandescent lamp, and the fluorescent lamp are not included, the light source is determined to be sunlight.

In step S143, it is determined whether or not the subject distance L is 5 m or more. As a result, if the distance L is more than 5 m, the process proceeds to step S144, in accordance with correction data in Table 5, the aberration correction amount g _1S0 inputted to AF correction data DerutaAFD0S. Then, this subroutine is exited.

On the other hand, if the subject distance L is less than 5 m in step S143, the process proceeds to step S145 to determine whether or not the subject distance L is between 2 m and 5 m. Here, if the between distance L is 2M～5m, the operation proceeds to Step S146, according to the correction data in Table 5, the aberration correction amount g _2S0 inputted to AF correction data DerutaAFD0S. Then, this subroutine is exited.

Furthermore, if the subject distance L is less than 2 m in step S145, the process proceeds to step S147 to determine whether or not the subject distance L is between 1 m and 2 m. Here, if the between distance L is 1 m to 2 m, the process proceeds to step S148, in accordance with correction data in Table 5, the aberration correction amount g _3S0 inputted to AF correction data DerutaAFD0S. Then, this subroutine is exited.

The distance L Te in step S147 is less than 1 m, the process proceeds to step S149, in accordance with correction data in Table 5, the aberration correction amount g _4S0 inputted to AF correction data DerutaAFD0S. Then, this subroutine is exited.

Table 6 below shows focus shift correction data corresponding to the light source stored in ΔAFD 1, 16 b of the data storage unit 16 in the interchangeable lens unit 10, similarly to Table 5 described above.

  This focus lens also has, for example, a closest shooting distance of 0.5 m, and has a defocus correction data obtained by dividing a subject distance of 0.5 m to infinity into four areas.

  21 and 22 illustrate the operation of a subroutine “light source determination / AF correction value (ΔAFD1S) selection” for correcting the focus shift using the focus shift correction data in Table 6 in the second embodiment. It is a flowchart.

  Hereinafter, this operation will be described.

When the subroutine “light source determination / AF correction value selection” in step S18 in the flowchart of FIG. 13 is entered, first in step S151, the flag [F_HOJO] is determined. If the flag [F_HOJO] is set, the process proceeds to step S152 to determine whether or not the subject distance L is 5 m or more. As a result, if the distance L is more than 5 m, the process proceeds to step S153, in accordance with correction data in Table 6, the aberration correction amount g _1h1 inputted to ΔAFD1S is data for AF correction. Then, this subroutine is exited.

On the other hand, if the subject distance L is less than 5 m in step S152, the process proceeds to step S154 to determine whether or not the subject distance L is between 2 m and 5 m. Here, if the between distance L is 2M～5m, the operation proceeds to Step S155, according to the correction data in Table 6, the aberration correction amount g _2h1 is input to the AF correction data DerutaAFD1S. Then, this subroutine is exited.

Furthermore, if the subject distance L is less than 2 m in step S154, the process proceeds to step S156 to determine whether or not the subject distance L is between 1 m and 2 m. Here, if the between distance L is 1 m to 2 m, the process proceeds to step S157, in accordance with correction data in Table 6, the aberration correction amount g _3h1 is input to the AF correction data DerutaAFD1S. Then, this subroutine is exited.

The distance L Te in step S156 is less than 1 m, the process proceeds to step S158, in accordance with correction data in Table 6, the aberration correction amount g _4h1 is input to the AF correction data DerutaAFD1S. Then, this subroutine is exited.

  On the other hand, if the flag [F_HOJO] is not set in step S151, the process proceeds to step S159 to determine whether or not the flag [F_BRUF] is set. If the flag [F_BRUF] is set, the process proceeds to step S160.

In step S160, it is determined whether or not the subject distance L is 5 m or more. As a result, if the distance L is more than 5 m, the process proceeds to step S161, in accordance with correction data in Table 6, the aberration correction amount g _1b1 is input to the AF correction data DerutaAFD1S. Then, this subroutine is exited.

On the other hand, if the subject distance L is less than 5 m in step S160, the process proceeds to step S162 to determine whether or not the subject distance L is between 2 m and 5 m. Here, if the between distance L is 2M～5m, the operation proceeds to Step S163, according to the correction data in Table 6, the aberration correction amount g _2b1 is input to the AF correction data DerutaAFD1S. Then, this subroutine is exited.

Further, if the subject distance L is less than 2 m in step S162, the process proceeds to step S164, and it is determined whether or not the subject distance L is between 1 m and 2 m. Here, if the between distance L is 1 m to 2 m, the process proceeds to step S165, in accordance with correction data in Table 6, the aberration correction amount g _3b1 is input to the AF correction data DerutaAFD1S. Then, this subroutine is exited.

The distance L Te in step S164 is less than 1 m, the process proceeds to step S166, in accordance with correction data in Table 6, the aberration correction amount g _4b1 is input to the AF correction data DerutaAFD1S. Then, this subroutine is exited.

  If the flag [F_BRUF] is not set in step S159, the process proceeds to step S167 to determine whether or not the flag [F_INFR] is set. If the flag [F_INFR] is set here, the process proceeds to step S169.

In step S169, it is determined whether or not the subject distance L is 5 m or more. As a result, if the distance L is more than 5 m, the process proceeds to step S170, in accordance with correction data in Table 6, the aberration correction amount g _1i1 is input to the AF correction data DerutaAFD1S. Then, this subroutine is exited.

On the other hand, if the subject distance L is less than 5 m in step S169, the process proceeds to step S171 to determine whether or not the subject distance L is between 2 m and 5 m. Here, if the between distance L is 2M～5m, the operation proceeds to Step S172, according to the correction data in Table 6, the aberration correction amount g _2i1 is input to the AF correction data DerutaAFD1S. Then, this subroutine is exited.

Further, if the subject distance L is less than 2 m in step S171, the process proceeds to step S173, and it is determined whether or not the subject distance L is between 1 m and 2 m. Here, if the between distance L is 1 m to 2 m, the process proceeds to step S174, in accordance with correction data in Table 6, the aberration correction amount g _3I1 are input to the AF correction data DerutaAFD1S. Then, this subroutine is exited.

The distance L Te in step S173 is less than 1 m, the process proceeds to step S175, in accordance with correction data in Table 6, the aberration correction amount g _4I1 are input to the AF correction data DerutaAFD1S. Then, this subroutine is exited.

  If the flag [F_INFR] is not set in step S167, the process proceeds to step S168 to determine whether or not the flag [F_FLUO] is set. If the flag [F_FLUO] is set, the process proceeds to step S176.

In step S176, it is determined whether or not the subject distance L is 5 m or more. As a result, if the distance L is more than 5 m, the process proceeds to step S177, in accordance with correction data in Table 6, the aberration correction amount g _1f1 is input to the AF correction data DerutaAFD1S. Then, this subroutine is exited.

On the other hand, if the subject distance L is less than 5 m in step S176, the process proceeds to step S178, and it is determined whether or not the subject distance L is between 2 m and 5 m. Here, if the between distance L is 2M～5m, the operation proceeds to Step S179, according to the correction data in Table 6, the aberration correction amount g _2f1 is input to the AF correction data DerutaAFD1S. Then, this subroutine is exited.

Further, if the subject distance L is less than 2 m in step S178, the process proceeds to step S180, and it is determined whether or not the subject distance L is between 1 m and 2 m. Here, if the between distance L is 1 m to 2 m, the process proceeds to step S181, in accordance with correction data in Table 6, the aberration correction amount g _3f1 is input to the AF correction data DerutaAFD1S. Then, this subroutine is exited.

The distance L Te in step S180 is less than 1 m, the process proceeds to step S182, in accordance with correction data in Table 6, the aberration correction amount g _4f1 is input to the AF correction data DerutaAFD1S. Then, this subroutine is exited.

  If the flag [F_FLUO] is not set in step S168, the process proceeds to step S183. In this case, since the auxiliary light, the blue flood lamp, the incandescent lamp, and the fluorescent lamp are not included, the light source is determined to be sunlight.

In step S183, it is determined whether or not the subject distance L is 5 m or more. As a result, if the distance L is more than 5 m, the process proceeds to step S184, in accordance with correction data in Table 6, the aberration correction amount g _1s1 is input to the AF correction data DerutaAFD1S. Then, this subroutine is exited.

On the other hand, if the subject distance L is less than 5 m in step S183, the process proceeds to step S185, and it is determined whether or not the subject distance L is between 2 m and 5 m. Here, if the between distance L is 2M～5m, the operation proceeds to Step S186, according to the correction data in Table 6, the aberration correction amount g _2s1 is input to the AF correction data DerutaAFD1S. Then, this subroutine is exited.

Further, if the subject distance L is less than 2 m in step S185, the process proceeds to step S187, and it is determined whether or not the subject distance L is between 1 m and 2 m. Here, if the between distance L is 1 m to 2 m, the process proceeds to step S188, in accordance with correction data in Table 6, the aberration correction amount g _3S1 inputted to AF correction data DerutaAFD1S. Then, this subroutine is exited.

The distance L Te in step S187 is less than 1 m, the process proceeds to step S189, in accordance with correction data in Table 6, the aberration correction amount g _4s1 is input to the AF correction data DerutaAFD1S. Then, this subroutine is exited.

Table 7 below shows correction data for correcting the focus shift correction data corresponding to the light source stored in the adapter storage unit 23 in the B-type intermediate adapter 20b, similar to Tables 5 and 6 described above. Is.

  This focus lens also has, for example, a closest shooting distance of 0.5 m, and has a defocus correction data obtained by dividing a subject distance of 0.5 m to infinity into four areas.

23 and 24 illustrate the operation of a subroutine “light source determination / correction coefficient (α _S ) selection” for correcting the focus shift using the focus shift correction data shown in Table 7 in the second embodiment. It is a flowchart.

  Hereinafter, this operation will be described.

  The focus lens position (= distance) is obtained from the lens CPU 15 by communication.

When the subroutine “light source determination / correction coefficient (α _S ) selection” in step S21 in the flowchart of FIG. 13 is entered, first in step S191, the flag [F_HOJO] is determined. Here, when the flag [F_HOJO] is set, the process proceeds to step S192 to determine whether or not the subject distance L is 5 m or more. As a result, if the distance L is more than 5 m, the process proceeds to step S193, in accordance with correction data in Table 7, the correction data alpha _1h is input to the correction coefficient alpha _S. Then return.

On the other hand, if the subject distance L is less than 5 m in step S192, the process proceeds to step S194 to determine whether or not the subject distance L is between 2 m and 5 m. Here, if the between distance L is 2M～5m, the operation proceeds to Step S195, according to the correction data in Table 7, the correction data alpha _2h is inputted to the correction coefficient alpha _S. Then return.

Further, if the subject distance L is less than 2 m in step S194, the process proceeds to step S196, and it is determined whether or not the subject distance L is between 1 m and 2 m. Here, if the between distance L is 1 m to 2 m, the process proceeds to step S197, in accordance with correction data in Table 7, the correction data alpha _3h is inputted to the correction coefficient alpha _S. Then return.

The distance L Te in step S196 is less than 1 m, the process proceeds to step S198, in accordance with correction data in Table 7, the correction data alpha _4h is inputted to the correction coefficient alpha _S. Then return.

  On the other hand, if the flag [F_HOJO] is not set in step S191, the process proceeds to step S199 to determine whether or not the flag [F_BRUF] is set. Here, when the flag [F_BRUF] is set, the process proceeds to step S200.

In step S200, it is determined whether or not the subject distance L is 5 m or more. As a result, if the distance L is more than 5 m, the process proceeds to step S201, in accordance with correction data in Table 7, the correction data alpha _1b is input to the correction coefficient alpha _S. Then return.

On the other hand, if the subject distance L is less than 5 m in step S200, the process proceeds to step S202, and it is determined whether or not the subject distance L is between 2 m and 5 m. Here, if the between distance L is 2M～5m, the operation proceeds to Step S203, according to the correction data in Table 7, the correction data alpha _2b is input to the correction coefficient alpha _S. Then return.

Furthermore, if the subject distance L is less than 2 m in step S202, the process proceeds to step S204, where it is determined whether or not the subject distance L is between 1 m and 2 m. Here, if the between distance L is 1 m to 2 m, the process proceeds to step S205, in accordance with correction data in Table 7, the correction data alpha _3b is input to the correction coefficient alpha _S. Then return.

The distance L Te in step S204 is less than 1 m, the process proceeds to step S206, in accordance with correction data in Table 7, the correction data alpha _4b is input to the correction coefficient alpha _S. Then return.

  If the flag [F_BRUF] is not set in step S199, the process proceeds to step S207 to determine whether or not the flag [F_INFR] is set. If the flag [F_INFR] is set, the process proceeds to step S209.

In step S209, it is determined whether or not the subject distance L is 5 m or more. As a result, if the distance L is more than 5 m, the process proceeds to step S210, in accordance with correction data in Table 7, the correction data alpha _1i is input to the correction coefficient alpha _S. Then return.

On the other hand, if the subject distance L is less than 5 m in step S209, the process proceeds to step S211 to determine whether or not the subject distance L is between 2 m and 5 m. Here, if the between distance L is 2M～5m, the operation proceeds to step S212, the following correction data in Table 7, the correction data alpha _2i are inputted to the correction coefficient alpha _S. Then return.

Further, if the subject distance L is less than 2 m in step S211, the process proceeds to step S213, and it is determined whether or not the subject distance L is between 1 m and 2 m. Here, if the between distance L is 1 m to 2 m, the process proceeds to step S214, the following correction data in Table 7, the correction data alpha _3i is input to the AF correction data alpha _S. Then return.

The distance L Te in step S213 is less than 1 m, the operation proceeds to step S215, the following correction data in Table 7, the correction data alpha _4i is input to the correction data DerutaAFD0S. Then return.

  If the flag [F_INFR] is not set in step S207, the process proceeds to step S208 to determine whether or not the flag [F_FLUO] is set. If the flag [F_FLUO] is set, the process proceeds to step S216.

In step S216, it is determined whether or not the subject distance L is 5 m or more. As a result, if the distance L is more than 5 m, the process proceeds to step S217, in accordance with correction data in Table 7, the correction data alpha _1f is input to the AF correction data alpha _S. Then return.

On the other hand, if the subject distance L is less than 5 m in step S216, the process proceeds to step S218, and it is determined whether or not the subject distance L is between 2 m and 5 m. Here, if the between distance L is 2M～5m, the operation proceeds to Step S219, according to the correction data in Table 7, the correction data alpha _2f are input to the correction coefficient alpha _S. Then return.

Furthermore, if the subject distance L is less than 2 m in step S218, the process proceeds to step S220, and it is determined whether or not the subject distance L is between 1 m and 2 m. Here, if the between distance L is 1 m to 2 m, the process proceeds to step S221, in accordance with correction data in Table 7, the correction amount data alpha _3f is input to the correction coefficient alpha _S. Then return.

The distance L Te in step S220 is less than 1 m, the process proceeds to step S222, in accordance with correction data in Table 7, the correction data alpha _4f is inputted to the correction coefficient alpha _S. Then return.

  If the flag [F_FLUO] is not set in step S208, the process proceeds to step S223. In this case, since the auxiliary light, the blue flood lamp, the incandescent lamp, and the fluorescent lamp are not included, the light source is determined to be sunlight.

In step S223, it is determined whether or not the subject distance L is 5 m or more. As a result, if the distance L is more than 5 m, the process proceeds to step S224, in accordance with correction data in Table 7, the correction data alpha _1s are input to the correction coefficient alpha _S. Then return.

On the other hand, the object distance L in step S 223 is less than 5 m, the process proceeds to step S225, L the object distance is equal to or between 2m~5m is determined. Here, if the between distance L is 2M～5m, the operation proceeds to Step S226, according to the correction data in Table 7, the correction data alpha _2s are input to the correction coefficient alpha _S. Then return.

Further, if the subject distance L is less than 2 m in step S225, the process proceeds to step S227 to determine whether or not the subject distance L is between 1 m and 2 m. Here, if the between distance L is 1 m to 2 m, the process proceeds to step S228, in accordance with correction data in Table 7, the correction data alpha _3s is inputted to the correction coefficient alpha _S. Then return.

The distance L Te in step S227 is less than 1 m, the process proceeds to step S229, in accordance with correction data in Table 7, the correction data alpha _4s is input to the correction coefficient alpha _S. Then return.

  Thereafter, the process proceeds to step S22 in the flowchart of FIG. 13, whereby an appropriate correction coefficient is obtained.

  As described above, the focus lens position, that is, the focus shift correction according to the type of the light source according to the distance is performed, so that it is possible to perform AF with higher accuracy.

  In the first and second embodiments described above, four types of light sources such as sunlight, fluorescent lamp, tungsten light (incandescent lamp), and blue flood lamp are detected, but not only these four types. It is also possible to detect a finer light source and perform accurate correction.

  The embodiment of the present invention has been described above, but it goes without saying that the present invention can be modified without departing from the gist of the present invention.

It is a block diagram which shows the basic composition of the camera system of this invention. The detection area of the AF sensor 46 and the detection area of the light source sensor 51 that constitute a part of the focus detection device in the camera system of the first embodiment of the present invention are schematically shown, and the detection areas are photographed. FIG. 6 is a diagram showing a relationship with respect to a screen (photographing angle of view) 55. It is the schematic which shows the spectral characteristic of the various illumination light sources which illuminate a to-be-photographed object. FIG. 6 is a diagram showing a state in which a gap between two images formed on the light receiving portion of the AF sensor 46 is shifted depending on the type of light source that illuminates the subject. In the camera system of 1st Embodiment, it measures the illumination light which illuminates a to-be-photographed object, and is the figure which each showed the spectral sensitivity characteristic of the visible light sensor 69, and the spectral sensitivity characteristic of the infrared light sensor 68. It is the figure which expressed and standardized the difference ((DELTA) BV) of the infrared photometry by a light source and a visible photometry on the basis of a tungsten lamp, and is the figure which showed the light source determination method in this embodiment. It is the figure shown about arrangement | positioning of the light source sensor 51. FIG. 3 is a plan view showing a configuration of a light source sensor 51. FIG. It is a figure which shows the structure of the 1st variation of the camera system which concerns on this invention. It is a figure which shows the structure of the 2nd variation of the camera system which concerns on this invention. It is a figure which shows the structure of the 3rd variation of the camera system which concerns on this invention. It is a general | schematic flowchart which shows the procedure in which camera CPU35 acquires lens information. It is a general | schematic flowchart which shows the procedure in which correction | amendment calculation of the amount of focus shifts for focusing is performed by camera CPU35. It is a flowchart explaining the detailed operation | movement of the subroutine "light source detection" of step S11 in the flowchart of FIG. 14 is a flowchart for explaining an operation of a subroutine “light source determination, AF correction value (ΔAFD0S) selection” in step S23 in the flowchart of FIG. 14 is a flowchart for explaining an operation of a subroutine “light source determination, AF correction value (ΔAFD01) selection” in step S18 in the flowchart of FIG. 14 is a flowchart for explaining an operation of a subroutine “light source determination, correction coefficient (α _S ) selection” in step S21 in the flowchart of FIG. It is the 2nd Embodiment of this invention, Comprising: It is the figure which showed the characteristic only about one type of light source. 14 is a flowchart for explaining the operation of a subroutine “light source determination / AF correction value (ΔAFD0S) selection” in step S23 in the flowchart of FIG. 13 according to the second embodiment of the present invention. 14 is a flowchart for explaining the operation of a subroutine “light source determination / AF correction value (ΔAFD0S) selection” in step S23 in the flowchart of FIG. 13 according to the second embodiment of the present invention. FIG. 14 is a flowchart illustrating an operation of a subroutine “light source determination / AF correction value (ΔAFD1S) selection” in step S18 in the flowchart of FIG. 13 according to the second embodiment of the present invention. FIG. 14 is a flowchart illustrating an operation of a subroutine “light source determination / AF correction value (ΔAFD1S) selection” in step S18 in the flowchart of FIG. 13 according to the second embodiment of the present invention. FIG. 14 is a flowchart for explaining an operation of a subroutine “light source determination / correction coefficient (α _S ) selection” in step S21 in the flowchart of FIG. 13 according to the second embodiment of the present invention. FIG. 14 is a flowchart for explaining an operation of a subroutine “light source determination / correction coefficient (α _S ) selection” in step S21 in the flowchart of FIG. 13 according to the second embodiment of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Interchangeable lens unit, 11a ... Shooting lens, 11b ... Shooting lens, 12 ... Aperture, 15 ... Lens CPU, 16 ... Data storage part, 16a ... Data for AF correction, 16b ... Data for AF correction, 20 ... Intermediate adapter, 20a ... A type intermediate adapter, 20b ... B type intermediate adapter, 22 ... adapter CPU, 23 ... adapter storage unit, 30 ... camera body unit, 31 ... quick return mirror, 35 ... camera CPU, 39 ... camera storage unit, 42 ... Photometric circuit 43... Auxiliary light section 46... AF sensor 47. Distance measuring section 50. Diffuser plate 51. Light source sensor 52.

Claims (3)

A camera system comprising a camera body, an interchangeable lens that includes a photographic lens and is attachable to and detachable from the camera body, and an intermediate adapter that is attachable between the interchangeable lens and the camera body,
The interchangeable lens
AF correction data determined based on the optical characteristics of the photographing lens and configured to correspond to the type of light source that illuminates the subject, and applied when the intermediate adapter is not attached A first AF correction data storage unit storing data;
A second AF correction data storage unit storing second AF correction data which is AF correction data to be applied when the intermediate adapter is mounted;
With
The above intermediate adapter
A correction coefficient storage unit for storing a correction coefficient for correcting the second AF correction data;
The camera body is
A light source detector that detects a light source that illuminates the subject;
A mounting determination unit that determines whether or not the intermediate adapter is mounted;
An adapter determination unit that determines whether or not the intermediate adapter is an intermediate adapter to which the second AF correction data can be applied when the mounting determination unit determines that the intermediate adapter is mounted;
When the adapter determination unit determines that the intermediate adapter is not an intermediate adapter to which the second AF correction data can be applied, the correction coefficient stored in the correction coefficient storage unit of the intermediate adapter is used. A correction unit for correcting the second AF correction data;
A focus detection unit that detects the amount of defocus when the interchangeable lens is mounted;
When the adapter determination unit determines that the intermediate adapter is not an intermediate adapter to which the second AF correction data can be applied, the defocus amount detected by the focus detection unit is used as the light source detection. A defocus amount correction unit that corrects using the second AF correction data corrected by the correction unit based on a detection result by the unit;
Camera system comprising: a. An interchangeable lens including a taking lens is a camera that can be attached and detached via an intermediate adapter,
A mounting determination unit that determines whether or not the intermediate adapter is mounted;
When it is determined by the mounting determination unit that the intermediate adapter is mounted, the intermediate adapter is determined based on the optical characteristics of the photographing lens stored in the storage unit in the interchangeable lens and the subject is selected. An adapter determination unit that determines whether or not the intermediate correction adapter is applicable to AF correction data having a configuration corresponding to the type of light source to be illuminated;
When the adapter determination unit determines that the intermediate adapter is not an intermediate adapter to which the AF correction data can be applied, the AF correction data is stored using the correction coefficient stored in the intermediate adapter. A correction unit to correct,
A focus detection unit that detects the amount of defocus when the interchangeable lens is mounted;
When the adapter determination unit determines that the intermediate adapter is not an intermediate adapter to which the AF correction data can be applied, the defocus amount detected by the focus detection unit is detected by the light source detection unit. Based on the result, a defocus amount correction unit that corrects using the second AF correction data corrected by the correction unit;
A camera comprising: An interchangeable lens that can be attached to and detached from the camera body via an intermediate adapter,
AF correction data determined based on the optical characteristics of the photographing lens and configured to correspond to the type of light source that illuminates the subject, and applied when the intermediate adapter is not attached A first AF correction data storage unit storing data;
A second AF correction data storage unit storing second AF correction data which is AF correction data to be applied when the intermediate adapter is mounted;
Comprising
If the second AF correction data does not correspond to the intermediate adapter attached to the interchangeable lens, the second AF correction data is stored in the correction coefficient storage unit of the intermediate adapter. Applied to the attached intermediate adapter.
An interchangeable lens characterized by that.

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