Lens device, imaging device, imaging system, control method for lens device, and program

Abstract

To provide a lens device capable of performing highly accurate autofocus. [Solution] A lens device (100) that can be attached to and removed from an imaging device (200) comprises a communication means (101) for communicating with the imaging device, a first lens (116) that changes aberration by insertion and removal from the optical path, and an acquisition means (107) that acquires a value relating to the state according to the amount of aberration using first information regarding whether or not the first lens is inserted into the optical path, and the communication means transmits the value to the imaging device.

Description

Technical Field

[0004] , , , , , , , , ,

[0006] , , , ,

[0005] , , , ,

[0007] , , ,

[0001] The present invention relates to a lens device, an imaging device, an imaging system, a control method for a lens device, and a program.

Background Art

[0002] By imaging using a lens device having a lens (soft focus lens) that intentionally generates spherical aberration, it is possible to impart a sense of foreground and background blur to a subject or obtain a soft image, such as a cinematic video.

[0003] Patent Document 1 discloses a method of using a detection result by higher-precision contrast AF when a detection result by phase difference AF (autofocus) does not satisfy a predetermined condition.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In an image obtained by imaging using a lens device having a soft focus lens, spherical aberration is large and contrast is weak. Therefore, with the method disclosed in Patent Document 1, contrast AF cannot be executed with high precision. <000003​​​​​​​​One aspect of the present invention is a lens device that can be attached to and detached from an imaging device, comprising: communication means for communicating with the imaging device; a first lens that changes aberration by insertion and removal from an optical path; and acquisition means for acquiring a value relating to the state corresponding to the amount of aberration using first information regarding whether or not the first lens is inserted into the optical path, wherein the communication means transmits the value to the imaging device.

[0008] Other objects and features of the present invention are described in the following examples. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a lens device capable of performing highly accurate autofocus. [Brief explanation of the drawing]

[0010] [Figure 1] This is a block diagram of the imaging system in Example 1. [Figure 2] This is a flowchart showing the process for generating soft focus degree information in Example 1. [Figure 3] This is a flowchart showing the AF control parameter setting process in Example 1. [Figure 4] This figure shows the relationship between the contrast peak and the peak detection threshold in Example 1. [Figure 5] This is a block diagram of the imaging system in Example 2. [Figure 6] This is a flowchart showing the AF method information generation process in Example 2. [Figure 7] This is a flowchart showing the AF enable / disable switching process in Example 2. [Figure 8] This is a flowchart showing the AF enable / disable switching process in Example 2. [Modes for carrying out the invention]

[0011] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0012] (Example 1) First, with reference to Figure 1, the imaging system 10 in Embodiment 1 of the present invention will be described. Figure 1 is a block diagram of the imaging system 10. The imaging system 10 includes a camera device (camera body, imaging device) 200 and a lens device (interchangeable lens) 100 that can be attached to or removed from the camera device 200. However, this embodiment is not limited to this and can also be applied to imaging devices in which the camera body and lens device are integrally configured. In imaging devices in which the camera body and lens device are integrally configured, a communication unit for communication between the camera body and lens device is not required.

[0013] First, the lens device 100 will be described. The lens device 100 includes a communication unit (communication means) 101, an aperture control unit 102, a zoom control unit 103, a focus control unit 104, a spherical aberration generation amount calculation unit 105, a soft focus lens information acquisition unit 106, and a degree information generation unit (acquisition means) 107. The lens device 100 also has an optical system (imaging optical system) equipped with an aperture (aperture aperture) 112, a zoom lens (third lens) 113, a focus lens (second lens) 114, and a soft focus lens (first lens) 116. The aperture 112 changes the aperture amount to adjust the amount of light. The zoom lens 113 moves in the optical axis direction when zooming. The focus lens 114 moves in the optical axis direction when focusing. The soft focus lens 116 is a lens that changes aberration by inserting and removing it from the optical axis (optical path).

[0014] The communication unit 101 is connected to the degree information generation unit 107 and acquires the soft focus degree information (a value related to the state according to the amount of aberration) generated by the degree information generation unit 107. The soft focus degree information is represented by a numerical value between, for example, 0 (%) and 100 (%). The communication unit 101 is also connected to the camera device 200 and can communicate with the camera device 200, and transmits the soft focus degree information acquired from the degree information generation unit 107 to the camera device 200. The communication unit 101 is further connected to the focus control unit 104 and transmits the drive command received from the camera device 200 to the focus control unit 104.

[0015] The aperture control unit 102 controls the position of the aperture 112 (aperture position, aperture amount). The aperture control unit 102 is connected to the spherical aberration generation amount calculation unit 105 and outputs information regarding the current aperture position (aperture amount) to the spherical aberration generation amount calculation unit 105.

[0016] The zoom control unit 103 controls the position of the zoom lens 113 (zoom position). The zoom control unit 103 is connected to the spherical aberration generation amount calculation unit 105 and outputs information regarding the current zoom position to the spherical aberration generation amount calculation unit 105.

[0017] [[ID=I1]] The focus control unit 104 controls the position of the focus lens 114 (focus position). The focus control unit 104 is connected to the spherical aberration generation amount calculation unit 105 and outputs information regarding the current focus position to the spherical aberration generation amount calculation unit 105. The focus control unit 104 also drives the focus lens 114 in the optical axis direction based on the drive command from the camera device 200 received via the communication unit 101.

[0018] The spherical aberration generation amount calculation unit 105 calculates the generation amount of spherical aberration using the obtained aperture position, zoom position, and focus position. The spherical aberration generation amount calculation unit 105 is also connected to the degree information generation unit 107, and outputs the calculated generation amount of spherical aberration (the second information regarding the state of the lens device 100) to the degree information generation unit 107. Spherical aberration has the characteristics that the spherical aberration decreases as the aperture 112 is stopped down, and that the spherical aberration changes (increases or decreases) according to the focus position and the zoom position. Therefore, if the aperture position, zoom position, and focus position are known, the design value of the generation amount of spherical aberration can be calculated. In this embodiment, it is not essential for the spherical aberration generation amount calculation unit 105 to use all of the aperture position, zoom position, and focus position, and the generation amount of spherical aberration may be calculated using information regarding at least one of the aperture position, zoom position, and focus position.

[0019] The soft focus lens information acquisition unit 106 is connected to the degree information generation unit 107. The soft focus lens information acquisition unit 106 outputs to the degree information generation unit 107 the presence / absence information of the soft focus lens as to whether the soft focus lens 116 is currently inserted (the first information regarding whether the soft focus lens 116 is inserted into the optical path).

[0020] The degree information generation unit 107 is connected to the spherical aberration generation amount calculation unit 105 and acquires the amount of spherical aberration. The degree information generation unit 107 is also connected to the soft focus lens information acquisition unit 106 and acquires information on the presence or absence of a soft focus lens 116 (first information). The degree information generation unit 107 uses the acquired amount of spherical aberration (second information) and the information on the presence or absence of a soft focus lens (first information) to generate soft focus degree information and outputs the generated soft focus degree information to the communication unit 101. For example, the degree information generation unit 107 has a memory (storage means) that stores a table showing the relationship between the presence or absence information of the soft focus lens 116 and the soft focus degree information, and can acquire soft focus degree information from the memory. This table may also be a table showing the relationship between the presence or absence information of the soft focus lens 116, the soft focus degree information, and information on the amount of spherical aberration (second information regarding the state of the lens device 100).

[0021] In this embodiment, the second piece of information is not essential when acquiring the soft focus degree information. That is, the degree information generation unit 107 can acquire the soft focus degree information using the first piece of information without using the second piece of information. Details of the generation of the soft focus degree information will be described later.

[0022] Next, the camera device 200 will be described. The camera device 200 includes a communication unit (communication means) 201, a threshold setting unit 202, an AF control parameter setting unit 203, an imaging unit 204, a video signal processing unit 205, an AF evaluation value calculation unit 206, and an AF control unit 207.

[0023] The communication unit 201 is connected to the lens device 100 and receives soft focus degree information generated by the lens device 100. The communication unit 201 is also connected to the AF control parameter setting unit 203 and outputs the received soft focus degree information to the AF control parameter setting unit 203.

[0024] The threshold setting unit 202 is a user interface for setting a threshold (first threshold) for soft focus degree information to switch AF control. The threshold can be set by the user, for example, between 0 (%) and 100 (%). The threshold setting unit 202 is also connected to the AF control parameter setting unit 203 and outputs the set threshold to the AF control parameter setting unit 203.

[0025] The AF control parameter setting unit 203 sets (changes) the parameters used for AF control (AF processing) based on the received soft focus degree information and threshold (based on the relationship between the soft focus degree information and the threshold). For example, the AF control parameter setting unit 203 selects whether to use the parameters for AF control as the parameters for the first AF control (first parameter) or the parameters for the second AF control corresponding to low contrast (second parameter). The AF control parameter setting unit 203 also sets the selected parameters as parameters for the AF control unit 207. Details of the AF control parameter setting process based on soft focus degree information and threshold will be described later.

[0026] The imaging unit 204 has an image sensor such as a CMOS (Complementary Metal-Oxide-Semiconductor) sensor or a CCD (Charge Coupled Device) sensor. The imaging unit 204 converts the optical image formed by the imaging optical system of the lens device 100 into an electrical image.

[0027] The video signal processing unit 205 is connected to the imaging unit 204 and generates a video signal. The AF evaluation value calculation unit 206 is connected to the video signal processing unit 205 and extracts a luminance signal from the video signal acquired from the video signal processing unit 205. The AF evaluation value calculation unit 206 also performs a filter on the extracted luminance signal to extract specific frequency components and calculate the AF evaluation value necessary for contrast AF control. The AF evaluation value calculation unit 206 is also connected to the AF control unit 207 and transmits the calculated AF evaluation value to the AF control unit 207.

[0028] The AF control unit 207 minutely drives the focus lens 114 of the lens device 100 via the communication unit 201 and obtains an AF evaluation value from the AF evaluation value calculation unit 206. The AF control unit 207 repeatedly minutely drives the focus lens 114 and obtains the AF evaluation value, searches for the peak of the AF evaluation value, and performs the focusing process. In this embodiment, the threshold setting unit 202, the AF control parameter setting unit 203, the AF evaluation value calculation unit 206, and the AF control unit 207 constitute the control means for performing AF processing.

[0029] With the above configuration, the camera device 200 can switch AF control (AF processing) parameters based on the soft focus degree information received from the lens device 100 and a threshold set by the user. Therefore, by setting a threshold in advance, the AF control parameters can be automatically switched according to the soft focus degree of the lens device 100. As a result, AF processing can be performed with high precision even when the soft focus lens 116, which realizes cinematic images, is inserted into the optical path.

[0030] Next, with reference to Figure 2, the soft focus degree information generation process (control method of the imaging system 10) in this embodiment will be described. Figure 2 is a flowchart of the soft focus degree information generation process. This process is performed periodically according to a computer program stored in the lens device 100.

[0031] First, in step S201, the degree information generation unit 107 obtains information on the presence or absence of the soft focus lens 116 (first information indicating whether or not the soft focus lens 116 is inserted in the optical path) from the soft focus lens information acquisition unit 106 and confirms the first information. If the first information indicates "soft focus lens present" (information indicating that the soft focus lens 116 is in a first state, inserted in the optical path), the process proceeds to step S202. On the other hand, if the first information indicates "soft focus lens absent" (information indicating that the soft focus lens 116 is in a second state, not inserted in the optical path), the process proceeds to step S206.

[0032] In step S202, the spherical aberration generation amount calculation unit 105 acquires the aperture position, zoom position, and focus position. Subsequently, in step S203, the spherical aberration generation amount calculation unit 105 uses the acquired aperture position, zoom position, and focus position to perform a table calculation and calculate the amount of spherical aberration. For example, the spherical aberration generation amount calculation unit 105 has a memory (storage means) that stores a table showing the relationship between the aperture position, zoom position, and focus position and the amount of spherical aberration, and can acquire desired data from the memory.

[0033] Next, in step S204, the degree information generation unit 107 generates soft focus degree information that corresponds to the amount of spherical aberration (for example, proportional to the amount of spherical aberration). Then, in step S205, the degree information generation unit 107 sets the soft focus degree information (generated value) generated in step 204 as the soft focus degree information, and this flow ends.

[0034] In step S206, the degree information generation unit 107 sets the soft focus degree information to 0 (%), and this flow ends.

[0035] In this embodiment, when the soft focus lens 116 is not inserted into the optical path, the soft focus degree information is set to 0 (%). On the other hand, when the soft focus lens 116 is inserted into the optical path, the soft focus degree information is set to a value corresponding to the amount of spherical aberration (for example, a value between 0 and 100 (%)). This makes it possible to automatically generate the soft focus degree information.

[0036] For example, if the amount of spherical aberration is at the maximum value of the design, the soft focus degree information is set to 100% and if it is at the minimum value, it is set to 0%. This makes it possible to generate soft focus degree information ranging from 0% to 100% according to the design value of the amount of spherical aberration. If the amount of spherical aberration is an intermediate value between the maximum and minimum values, the soft focus degree information is set to, for example, 50%. In this embodiment, the soft focus degree information is smaller when the soft focus lens 116 is not inserted into the optical path (second state) than when the soft focus lens 116 is inserted into the optical path (first state).

[0037] Next, with reference to Figure 3, the AF control parameter setting process (control method of the imaging system 10) in this embodiment will be described. Figure 3 is a flowchart of the AF control parameter setting process. This process is performed periodically according to a computer program stored in the camera device 200.

[0038] First, in step S301, the AF control parameter setting unit 203 compares the soft focus degree information received from the lens device 100 with the threshold value set by the threshold value setting unit 202. If the soft focus degree information is greater than the threshold value, the process proceeds to step S302. On the other hand, if the soft focus degree information is less than or equal to the threshold value, the process proceeds to step S303.

[0039] In step S302, the AF control parameter setting unit 203 sets the parameters for the AF processing as parameters for the second AF control (second parameter), which executes a peak search method that matches the characteristic of the contrast AF where the change in the AF evaluation value is small even near the focus position.

[0040] In step S303, the AF control parameter setting unit 203 sets the parameters for the first AF control (first parameter), which executes a peak search method that matches the characteristic of contrast AF where the AF evaluation value changes significantly near the focus position, as parameters for the AF processing.

[0041] Next, in step S304, the AF control unit 207 executes AF processing using the AF control parameters (first parameter or second parameter) set in the AF control parameter setting unit 203, and this flow ends.

[0042] In this embodiment, by comparing the degree of soft focus information with a threshold set by the user, AF control suitable for situations where the contrast is weak with a soft focus lens inserted becomes possible, but only within the range of soft focus degree acceptable to the user.

[0043] For example, in the parameters for the second AF control, one of the parameters, the "contrast AF peak determination threshold (second threshold)," is changed to match the degree of soft focus. Figures 4(a) and 4(b) show the relationship between the contrast peak and the peak determination threshold (second threshold). Figure 4(a) shows the case when the soft focus lens 116 is not inserted, and Figure 4(b) shows the case when the soft focus lens 116 is inserted.

[0044] As the degree of soft focus increases, the contrast weakens, making it difficult to find peaks and potentially preventing autofocus from completing. For this reason, it is preferable to set parameters for the second AF control that lower the peak detection threshold as the degree of soft focus increases. In other words, it is preferable that the peak detection threshold differs according to the degree of soft focus information. For example, if the degree of soft focus is 50%, the peak detection threshold TH2 of the second AF control becomes 50% of the peak detection threshold TH1 set in the first AF control parameters.

[0045] In this way, by changing the peak detection threshold, which ensures the reliability of AF detection, to a value that is adapted to the low-contrast state when the soft-focus lens 116 is inserted, AF control can be performed while preserving cinematic images.

[0046] According to this embodiment, even when the contrast is weak when the soft-focus lens 116 is inserted, the state of the lens device 100 can be determined and the content of the AF control can be switched to provide AF while retaining the desired image.

[0047] In this embodiment, the parameters for the second AF control were described as changing the threshold for the contrast AF peak determination according to the degree of soft focus, but it is not always necessary to change the peak determination threshold. Any parameter that allows AF control to be performed while preserving a cinematic image, according to the degree of soft focus, is sufficient.

[0048] For example, in the case of contrast AF without a peak detection threshold, widening the search width (lens drive width) according to the degree of soft focus allows for faster peak search completion, even when the contrast peak is gradual and the search takes time. In other words, the parameters may include a parameter related to the search width during peak search in contrast AF. In this case, it is preferable that the search width is wider in the case of the second parameter than in the case of the first parameter. Furthermore, the search width may vary depending on the degree of soft focus information.

[0049] Furthermore, although the ratio of the soft focus degree to the reduction of the peak judgment threshold for the second AF control parameter was explained as "1:1" when the soft focus degree is 50%, it may be configured so that the user can set it arbitrarily.

[0050] Furthermore, the amount of spherical aberration varies from one individual to another. For this reason, the manufacturing error in the amount of spherical aberration may be measured and stored in advance, and this manufacturing error may be included when calculating the amount of spherical aberration. Also, the amount of spherical aberration varies depending on the temperature. For this reason, the temperature error in the amount of spherical aberration may be measured and stored in advance, and this temperature error may be included when calculating the amount of spherical aberration.

[0051] (Example 2) Next, with reference to Figure 5, the imaging system 10a in Embodiment 2 of the present invention will be described. Figure 5 is a block diagram of the imaging system 10a. The imaging system 10a includes a camera device (camera body, imaging device) 200a and a lens device (interchangeable lens) 100a that can be attached to or removed from the camera device 200a. However, this embodiment is not limited to this, and can also be applied to imaging devices in which the camera body and lens device are integrally configured. In this embodiment, the same reference numerals are used for functions and components that are the same as in Embodiment 1, and their descriptions are omitted.

[0052] Lens device 100a differs from lens device 100 of Embodiment 1 in that a branching prism 108, pupil division mechanism 109, AF evaluation value calculation unit 110, and AF control unit 111 are added. Camera device 200a differs from camera device 200 of Embodiment 1 in that the AF control parameter setting unit 203 is removed and an AF method switching unit 208 is added.

[0053] The communication unit 101 is connected to the camera device 200a and receives AF method information through communication with the camera device 200a. The communication unit 101 is also connected to the AF control unit 111 and outputs the AF method information received from the camera device 200a to the AF control unit 111. The focus control unit 104 is connected to the AF control unit 111 and drives the focus lens 114 in the optical axis direction based on the defocus amount obtained from the AF control unit 111.

[0054] The branching prism 108 branches off a portion of the light from the subject. The pupil splitting mechanism 109 splits the light branched by the branching prism 108 into two light beams for AF control. The AF evaluation value calculation unit 110 forms an image of the pair of light beams split by the pupil splitting mechanism 109 and uses the phase difference between the two formed images to calculate the AF evaluation value required for phase-difference AF. The AF evaluation value calculation unit 110 is also connected to the AF control unit 111 and notifies the AF control unit 111 of the calculated AF evaluation value.

[0055] The AF control unit 111 uses AF method information obtained from the communication unit 101 to switch between enabling and disabling the second AF method (second system), which is phase-detection AF. When phase-detection AF is enabled, the AF control unit 111 uses the AF evaluation value obtained from the AF evaluation value calculation unit 110 to determine whether or not the image is in focus. If the image is not in focus, the AF control unit 111 calculates the amount of defocus needed to achieve focus based on the AF evaluation value and the current position information of the focus lens 114. The AF control unit 111 is also connected to the focus control unit 104, and if the image is not in focus, it outputs a command to the focus control unit 104 to drive the amount of defocus and perform the focusing operation. Details of the AF enable / disable switching process in the AF control unit 111 using AF method information will be described later.

[0056] The communication unit 201 is connected to the lens device 100a and transmits the AF method information generated by the AF method switching unit 208 to the lens device 100a. The communication unit 201 is also connected to the AF method switching unit 208 and outputs the soft focus degree information (a value related to the state according to the amount of aberration) received from the lens device 100a to the AF method switching unit 208. The threshold setting unit 202 is connected to the AF method switching unit 208 and outputs the set threshold to the AF method switching unit 208.

[0057] The AF control unit 207 uses the AF method information obtained from the AF method switching unit 208 to switch between enabling and disabling the first AF method (first system), which is contrast AF. Details of the AF enable / disable switching process in the AF control unit 207 using the AF method information will be described later.

[0058] The AF method switching unit 208 generates AF method information based on the received soft focus degree information and threshold. The AF method information indicates whether to set the AF method used for AF processing to the first AF method, or to set it to the second AF method, which is more accurate than the first AF method when the soft focus lens 116 is inserted. The AF method switching unit 208 is also connected to the communication unit 201 and the AF control unit 207, and outputs the generated AF method information. Details of the AF method information generation process based on the soft focus degree information and threshold will be described later.

[0059] In this embodiment, with the above configuration, AF method information is generated based on the soft focus degree information received from the lens device 100a and a threshold set by the user, and the AF method can be switched using the AF method information. Therefore, by setting a threshold in advance, the AF method can be automatically switched according to the soft focus degree of the lens device 100a. As a result, the accuracy of AF is improved even when a soft focus lens 116 that realizes cinematic images is inserted.

[0060] Next, with reference to Figure 6, the AF method information generation process in this embodiment will be described. Figure 6 is a flowchart of the AF method information generation process. This process is performed periodically according to a computer program stored in the camera device 200a.

[0061] First, in step S601, the AF method switching unit 208 determines whether the currently set AF method by the user is contrast AF, which is the first AF method (i.e., whether the first AF method is active). If the set AF method is contrast AF, the process proceeds to step S602. On the other hand, if the set AF method is not contrast AF, the process proceeds to step S603.

[0062] In step S602, the AF method switching unit 208 compares the soft focus degree information received from the lens device 100aa with the threshold value set by the threshold value setting unit 202. If the soft focus degree information is greater than the threshold value, the process proceeds to step S603. On the other hand, if the soft focus degree information is less than or equal to the threshold value, the process proceeds to step S604.

[0063] In step S603, the AF method switching unit 208 sets the phase-detection AF, which is the second AF method with higher AF accuracy than the first AF method when the soft-focus lens 116 is inserted, as the AF method information, and this flow ends. In step S604, the AF method switching unit 208 sets the contrast AF, which is the first AF method, as the AF method information, and this flow ends.

[0064] According to this embodiment, even when the user has selected contrast AF, the AF method information can be automatically set to phase-detection AF only within the range of soft focus acceptable to the user, by comparing the degree of soft focus information with a threshold set by the user.

[0065] Next, with reference to Figure 7, the AF enable / disable switching process of the AF control unit 111 using the AF method information in this embodiment will be described. Figure 7 is a flowchart of the AF enable / disable switching process. This process is performed periodically according to the computer program stored in the lens device 100a.

[0066] First, in step S701, the AF control unit 111 determines the AF method information received from the camera device 200aa. If the AF method information is the second AF method, the process proceeds to step S702. On the other hand, if the AF method information is not the second AF method, the process proceeds to step S703.

[0067] In step S702, the AF control unit 111 enables AF processing, and this flow ends. In step S703, the AF control unit 111 disables AF processing, and this flow ends.

[0068] In this embodiment, AF method information generated from soft focus degree information and a threshold is used to switch the AF enabled / disabled state of the lens device 100aa. This allows phase-detection AF to be enabled when the contrast is weak while the soft focus lens 116 is inserted.

[0069] Next, with reference to Figure 8, the AF enable / disable switching process of the AF control unit 207 using the AF method information in this embodiment will be described. Figure 8 is a flowchart of the AF enable / disable switching process. This process is performed periodically according to the computer program stored in the camera device 200a.

[0070] First, in step S801, the AF control unit 207 determines the AF method information received from the AF method switching unit 208. If the AF method information is for the first AF method, the process proceeds to step S802. On the other hand, if the AF method information is not for the first AF method, the process proceeds to step S803.

[0071] In step S802, the AF control unit 207 enables AF processing, and this flow ends. In step S803, the AF control unit 207 disables AF processing, and this flow ends.

[0072] In this embodiment, the AF (autofocus) enabled / disabled state of the camera device 200a is switched using AF method information generated from soft focus degree information and a threshold. This allows contrast AF to be disabled when the contrast is weak while the soft focus lens 116 is inserted.

[0073] For example, in the lens device 100a, the AF optical system is configured before the soft focus lens 116, so the accuracy of the AF is not affected even when the soft focus lens 116 is inserted. For this reason, when the soft focus lens 116 is inserted and the contrast is weak, the AF accuracy of phase-detection AF is higher than that of the first AF method, contrast AF. Therefore, it is preferable to prioritize the more accurate phase-detection AF for users who are using contrast AF instead of phase-detection AF. According to this embodiment, when the soft focus lens 116 is inserted, it is possible to automatically switch to phase-detection AF only within the range of soft focus tolerance acceptable to the user.

[0074] As described above, the control means that perform AF processing (threshold setting unit 202, AF control unit 207, and AF method switching unit 208) changes the AF processing method based on the relationship between the degree of soft focus information and the first threshold. Preferably, the control means sets the method to the first method (first AF method) when the degree of soft focus information is less than the first threshold, and sets the method to the second method (second AF method) when the degree of soft focus information is greater than the first threshold. More preferably, the first method is a contrast detection method (contrast AF), and the second method is a phase difference detection method (phase difference AF).

[0075] In this embodiment, even when the contrast is weak with the soft-focus lens 116 inserted, the state of the lens device 100a is determined and the AF method is switched. This makes it possible to perform AF processing while retaining the desired image.

[0076] In this embodiment, the second AF method was described as phase-detection AF, but it is not limited to this. Similar effects can be obtained by using a contrast-independent AF method, such as an image plane phase-detection method (image plane phase-detection AF) that uses image data output from the imaging unit 204, as the second AF method.

[0077] (Other examples) The present invention can also be realized by supplying a program that implements one or more of the functions of the above-described embodiments to a system or device via a network or storage medium, and by having one or more processors in the computer of that system or device read and execute the program. It can also be realized by a circuit (e.g., an ASIC) that implements one or more functions.

[0078] Each embodiment provides a lens device, imaging device, imaging system, control method for the lens device, and program capable of performing high-precision autofocus.

[0079] Each embodiment's disclosure includes the following configuration and method. (Composition 1) A lens device that can be attached to and detached from an imaging device, A communication means for communicating with the aforementioned imaging device, A first lens that modifies aberrations by insertion and removal from the optical path, The system includes an acquisition means that uses first information regarding whether or not the first lens is inserted into the optical path to acquire a value relating to the state corresponding to the amount of aberration, The lens device is characterized in that the communication means transmits the value to the imaging device. (Configuration 2) The first information includes information indicating that the first lens is in a first state where it is inserted into the optical path, or that the first lens is in a second state where it is not inserted into the optical path. The lens device according to configuration 1, characterized in that the value is smaller when the first lens is in the second state than when it is in the first state. (Composition 3) The lens device according to configuration 1 or 2, characterized in that the acquisition means acquires the value using second information relating to the state of the lens device. (Composition 4) It further has a second lens that moves during focusing, The lens device according to configuration 3, characterized in that the second information includes information relating to the position of the second lens. (Composition 5) It further has a third lens that moves during zooming, The lens device according to configuration 3 or 4, characterized in that the second information includes information relating to the position of the third lens. (Composition 6) The second lens moves during focusing, It further includes a third lens that moves during zooming, The lens apparatus according to configuration 3, characterized in that the second information includes information regarding the position of the second lens and information regarding the position of the third lens. (Composition 7) It further has an aperture diaphragm for adjusting the amount of light, The lens device according to any one of configurations 3 to 6, characterized in that the second information includes information regarding the aperture amount of the aperture diaphragm. (Composition 8) The system further includes a storage means for storing a table that shows the relationship between the first information and the value, The lens device according to any one of configurations 1 to 7, characterized in that the acquisition means acquires the value from the storage means. (Composition 9) An imaging device having a lens device that can be attached and detached, the lens device having a first lens that changes aberration by insertion and removal into the optical path, Image sensor and It has communication means for communicating with the aforementioned lens device, The imaging device is characterized in that the communication means receives from the lens device a value relating to the state corresponding to the amount of aberration, which is obtained using first information regarding whether or not the first lens is inserted into the optical path. (Composition 10) Image sensor and A first lens that modifies aberrations by insertion and removal from the optical path, An imaging apparatus characterized by having an acquisition means that acquires a value relating to the state corresponding to the amount of aberration, using first information regarding whether or not the first lens is inserted into the optical path. (Composition 11) The system further includes control means for performing AF processing, The imaging apparatus according to configuration 9 or 10, characterized in that the control means changes the parameters used in the AF processing based on the relationship between the value and the first threshold. (Composition 12) The control means is If the aforementioned value is smaller than the first threshold, the parameter is set to the first parameter. The imaging apparatus according to configuration 11, characterized in that if the aforementioned value is greater than the first threshold, the parameter is set to the second parameter. (Composition 13) The aforementioned parameters include parameters relating to the second threshold for peak determination in contrast AF, The imaging apparatus according to configuration 12, characterized in that the second threshold is lower in the case of the second parameter than in the case of the first parameter. (Composition 14) The imaging apparatus according to configuration 13, characterized in that the second threshold for peak determination differs according to the value. (Composition 15) The aforementioned parameters include parameters relating to the search width during peak search in contrast AF. The imaging apparatus according to any one of configurations 12 to 14, characterized in that the search width is wider in the case of the second parameter than in the case of the first parameter. (Composition 16) The imaging device according to configuration 15, characterized in that the search width varies according to the value. (Composition 17) The system further includes control means for performing AF processing, The imaging apparatus according to configuration 9 or 10, characterized in that the control means changes the AF processing method based on the relationship between the value and the first threshold. (Composition 18) The control means is If the aforementioned value is smaller than the first threshold, the method is set to the first method. The imaging apparatus according to configuration 17, characterized in that if the aforementioned value is greater than the first threshold, the method is set to the second method. (Composition 19) The first method is a contrast detection method, The imaging apparatus according to configuration 18, characterized in that the second method is a phase difference detection method. (Composition 20) The first method is a contrast detection method, The imaging apparatus according to configuration 18, characterized in that the second method is an image plane phase difference method using image data output from the image sensor. (Composition 21) An imaging system characterized by comprising a lens device according to any one of configurations 1 to 8 and an imaging device. (Method 1) A method for controlling a lens device that can be attached to or detached from an imaging device, A step of obtaining a value relating to the state corresponding to the amount of aberration, using first information regarding whether or not a first lens that changes aberration by insertion into or removal from the optical path is inserted into the optical path, A method for controlling a lens device, characterized by comprising the step of transmitting the aforementioned value to the imaging device. (Composition 22) A program characterized by causing a computer to execute the lens device control method described in Method 1.

[0080] Although preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of its essence. [Explanation of Symbols]

[0081] 100, 100a Lens device 101 Communications Department 107 Degree information generation unit (acquisition means) 116 Soft focus lens (first lens) 200, 200a Camera device (imaging device)

Claims

1. A lens device that can be attached to and detached from an imaging device, A communication means for communicating with the aforementioned imaging device, A first lens that modifies aberrations by insertion and removal from the optical path, The system includes an acquisition means that uses first information regarding whether or not the first lens is inserted into the optical path to acquire a value relating to the state corresponding to the amount of aberration, The lens device is characterized in that the communication means transmits the value to the imaging device.

2. The first information includes information indicating that the first lens is in a first state where it is inserted into the optical path, or that the first lens is in a second state where it is not inserted into the optical path. The lens device according to claim 1, characterized in that the value is smaller when the first lens is in the second state than when it is in the first state.

3. The lens device according to claim 1, characterized in that the acquisition means acquires the value using second information relating to the state of the lens device.

4. It further has a second lens that moves during focusing, The lens apparatus according to claim 3, characterized in that the second information includes information regarding the position of the second lens.

5. It further has a third lens that moves during zooming, The lens apparatus according to claim 3, characterized in that the second information includes information relating to the position of the third lens.

6. The second lens moves during focusing, It further includes a third lens that moves during zooming, The lens apparatus according to claim 3, characterized in that the second information includes information regarding the position of the second lens and information regarding the position of the third lens.

7. It further has an aperture diaphragm for adjusting the amount of light, The lens device according to claim 3, characterized in that the second information includes information regarding the aperture amount of the aperture diaphragm.

8. The system further includes a storage means for storing a table that shows the relationship between the first information and the value, The lens device according to claim 1, characterized in that the acquisition means acquires the value from the storage means.

9. An imaging device having a lens device that can be attached and detached, the lens device having a first lens that changes aberration by insertion and removal into the optical path, Image sensor and It has communication means for communicating with the aforementioned lens device, The imaging device is characterized in that the communication means receives from the lens device a value relating to the state corresponding to the amount of aberration, which is obtained using first information regarding whether or not the first lens is inserted into the optical path.

10. Image sensor and A first lens that modifies aberrations by insertion and removal from the optical path, An imaging apparatus characterized by having an acquisition means that acquires a value relating to the state corresponding to the amount of aberration, using first information regarding whether or not the first lens is inserted into the optical path.

11. It further has control means for performing AF processing, The imaging apparatus according to claim 9 or 10, characterized in that the control means changes the parameters used in the AF processing based on the relationship between the value and the first threshold.

12. The control means is If the aforementioned value is smaller than the first threshold, the parameter is set to the first parameter. The imaging apparatus according to claim 11, characterized in that if the aforementioned value is greater than the first threshold, the parameter is set to the second parameter.

13. The aforementioned parameters include parameters relating to the second threshold for peak determination in contrast AF, The imaging apparatus according to claim 12, characterized in that the second threshold is lower in the case of the second parameter than in the case of the first parameter.

14. The imaging apparatus according to claim 13, characterized in that the second threshold for peak determination differs according to the value.

15. The aforementioned parameters include parameters relating to the search width during peak search in contrast AF. The imaging apparatus according to claim 12, characterized in that the search width is wider in the case of the second parameter than in the case of the first parameter.

16. The imaging device according to claim 15, characterized in that the search width varies according to the value.

17. It further has control means for performing AF processing, The imaging apparatus according to claim 9 or 10, characterized in that the control means changes the AF processing method based on the relationship between the value and the first threshold.

18. The control means is If the aforementioned value is smaller than the first threshold, the method is set to the first method. The imaging apparatus according to claim 17, characterized in that if the aforementioned value is greater than the first threshold, the method is set to the second method.

19. The first method is a contrast detection method, The imaging apparatus according to claim 18, characterized in that the second method is a phase difference detection method.

20. The first method is a contrast detection method, The imaging apparatus according to claim 18, characterized in that the second method is an image plane phase difference method that uses image data output from the image sensor.

21. An imaging system characterized by comprising a lens device according to any one of claims 1 to 8 and an imaging device.

22. A method for controlling a lens device that can be attached to or detached from an imaging device, A step of obtaining a value relating to the state corresponding to the amount of aberration, using first information regarding whether or not a first lens that changes aberration by insertion into or removal from the optical path is inserted into the optical path, A method for controlling a lens device, characterized by comprising the step of transmitting the aforementioned value to the imaging device.

23. A program characterized by causing a computer to execute the control method for the lens device described in claim 22.

Images