JP5606053B2 - Imaging apparatus and image processing method - Google Patents

Description

  The present invention relates to an imaging apparatus.

  Conventionally, when an additional optical system is connected to a photographing apparatus and a subject image is formed by an even-number imaging method of two or more times, there is a problem that the image is reversed vertically and horizontally. On the other hand, with respect to television systems and liquid crystal projectors, proposals have been made to invert and rotate images (Patent Documents 1 and 2).

JP-A-4-192678 JP 2005-24573 A

  However, Patent Document 1 and Patent Document 2 do not specifically show an automatic upper / lower and left / right reversal discriminating means, and the user has to perform a switching operation manually.

  The present invention provides an imaging apparatus to which an imaging optical system is added so that an object image can be formed by an even-number imaging method of two or more times and an output image can be automatically set to a normal position image. For illustrative purposes.

An imaging apparatus according to an aspect of the present invention includes a photographing optical system that forms a subject image, an imaging element that photoelectrically converts a subject image formed by the photographing optical system, and an imaging optical system that is added to the photographing optical system. And an optical device including the imaging optical system and the housing for housing the imaging device, image processing means for processing the output of the imaging device, and detecting the movement of the housing in the pan movement direction and the tilt movement direction. First movement detection means, second movement detection means for detecting an image movement direction that is a movement direction of the subject image based on an output of the image sensor, the first movement detection means, and the second movement detection means. and a control means for controlling the image processing including the flip or rotate by the image processing unit by comparing the output of said control means, prior to the housing detected by the first movement detecting means When it is determined that the pan movement direction and the image movement direction detected by the second movement detection unit match, the image processing unit reverses the output image signal obtained from the output of the image sensor, and When it is determined that the tilt movement direction of the housing detected by the first movement detection unit matches the image movement direction detected by the second movement detection unit, the output image signal is moved up and down by the image processing unit. It is characterized by being inverted.

  It is an object of the present invention to provide an imaging apparatus that can add an imaging optical system to form a subject image by an even-number imaging method of two or more times and can automatically set an output image as a normal position image. it can.

It is an optical path diagram of an imaging device (optical device) to which the attachment optical system and the photographing optical system of the present embodiment are connected. 2A is an optical path diagram showing a state in which the imaging apparatus of FIG. 1 forms an image of an object at infinity twice, and FIG. 2B shows a reflection member on the objective optical system of FIG. It is an optical path diagram which shows the state which inserted and bent the objective optical system. It is a schematic sectional drawing of the digital camera with which the attachment optical system shown in FIG. 2 was mounted | worn. It is a flowchart of the image processing which the processor shown in FIG. 3 performs. It is a block diagram of the control system of a present Example.

FIG. 1 is an optical path diagram of a digital camera (imaging device) in which an attachment optical system (optical device) A is mounted on the object side of the photographing optical system M. When the attachment optical system A is mounted, the photographic optical system of the imaging apparatus that forms a subject image together with the photographic optical system M is configured. SP is an iris diaphragm, FIL is a filter such as an infrared cut or low pass, and IP is an image plane.
In this embodiment, an imaging optical system is provided on the object side of a general-purpose imaging optical system (re-imaging optical system) that is a variable magnification optical system, such as a digital compact camera (imaging device). An attachment optical system is detachably connected to realize a two-time imaging optical system. The imaging apparatus can obtain a super-wide shooting field angle without increasing the lens outer diameter by the two-time imaging optical system of the attachment optical system and the shooting optical system. Of course, the attachment optical system A may form an even number of images more than twice together with the photographing optical system M.

  The attachment optical system A includes an objective optical system B1, a field lens group B2, and a correction lens group B3 in order from the object side. The objective optical system B1 as a whole has a positive refractive power. Although not essential, the field lens group B2 is disposed in the vicinity of the imaging position of the objective optical system B1, has a positive refractive power, deflects off-axis rays, and guides them to the imaging optical system M. The correction lens unit B3 emits the axial ray from the attachment optical system A as a parallel light and has a positive refractive power. The correction lens group B3 is closer to the photographing optical system M than the objective optical system B1. The correction lens group B3 has a function of focusing the aerial image formed by the objective optical system B1 on the position of the imaging plane IP of the photographing optical system M.

  Preferably, the objective optical system B1 includes a front lens unit B1a having a negative refractive power, which is composed of two negative lenses each having a strong concave surface on the image side in order from the object side. Decreasing the curvature of the surface to reduce the occurrence of astigmatism. The objective optical system B1 is a rear lens having a positive refractive power composed of a cemented lens having a positive refractive power and a convex lens, the whole of which a positive lens and a negative lens are cemented in order from the object side with an air gap therebetween. It has group B1b.

  The field lens unit B2 includes a positive lens having a convex shape on the object side in order from the object side and a negative lens having a concave shape on the object side with an air gap interposed therebetween. After the incident light is deflected by the positive lens, the negative lens on the image side corrects the spherical aberration. As a result, the light emitted from the field lens group becomes near-parallel light, and it is possible to prevent peripheral vignetting of an image that is re-imaged through the relay lens group.

  The correction lens group B3 preferably has a doublet in which a positive lens and a negative lens are combined in order to suppress the occurrence of chromatic aberration.

  The photographing optical system M has a four-group configuration including a positive lens group MB1, a negative lens group MB2, a positive lens group MB3, and a positive lens group MB4 in order from the object side. The photographic optical system M performs the zooming operation by changing the distance between the lens groups, and at the same time, moves the lens groups so that the position of the image plane does not change. Further, the photographing optical system M performs a focusing action by moving the lens group MB4 in the optical axis direction. The photographing optical system M may have a two-group configuration including a negative lens group and a positive lens group in order from the object side. In this case, the photographic optical system M has a variable magnification structure that does not cause a focal point movement even during variable magnification by changing the position from the imaging plane IP together with the change in the distance between both lens groups, and the focusing function is a positive lens. This is done by moving the group in the direction of the optical axis.

  FIG. 2A is an optical path diagram showing a state in which a subject image at infinity is formed twice by the imaging apparatus shown in FIG. 1, and the subject image by this optical system is relative to the original upright subject image. Upside down and left and right are reversed.

  FIG. 2B shows a state in which the photographing direction is deflected by inserting the reflecting member R into the objective optical system B1 of the imaging apparatus of FIG. 1 and bending the front lens group B1a of the objective optical system B1 at the same time. FIG. Since the subject image by the optical system shown in FIG. 2B is reversed in the deflection direction with respect to the state before the reflection member R is inserted, the subject image by this optical system is different from the original upright subject image. The left and right are reversed. The insertion position of the reflecting member R is not limited.

  FIG. 3 is a schematic cross-sectional view showing a state in which the attachment optical system A is attached to the digital camera (imaging device) 100. In the digital camera 100, an attachment optical device 120 that houses the attachment optical system A is replaceably mounted on the object side of the converter attachment 110 that houses the photographing optical system M. The converter attachment 110 is an adapter ring attached to the digital camera 100 and is an intermediate member for fixing the attachment optical device 120 to the digital camera 100.

  At the tip of the attachment optical device 120, a light shielding member 124 that houses a reflecting member R and has a lens barrel 122 that houses the front lens group B1a of the objective optical system B1 on the object side is attached. The light shielding member 124 is made of a stretchable material such as a bellows or a rubber material, and functions as means for inserting and retracting the reflecting member R in the optical path. The reflecting member R is inserted into the air space portion of the objective optical system B1, and deflects the optical path by 90 ° as shown in FIG. The reflecting member R can be retracted by rotation. At the same time, after the reflecting member R is retracted, if the front lens group B1a of the objective optical system B1 is disposed on the optical axis, the reflecting member R is rotated in the direction of the arrow. An optical system having a straight structure shown in FIG.

  The digital camera 100 further includes a liquid crystal monitor (display unit) 101b, an attitude detection unit 102, a camera movement detection unit 103, an image sensor 104, an image movement detection unit 105, a processor 106, and a housing 101a for housing them.

  The posture detection means 102 detects the horizontal position and the vertical position. The camera movement detection unit 103 is a first movement detection unit that detects the movement of the casing 101a in the pan (horizontal) direction and the tilt (vertical) direction. In FIG. 3, the camera movement detection unit 103 detects two axes of pan and tilt at the same time. However, the camera movement detection unit 103 may be configured by two detection units independent of pan and tilt. May further have the function of the posture detection means 102. The posture detection means 102 and the camera movement detection means 103 convert the output of an angle detector such as a vibration gyro into an angle signal by an unillustrated integration process and output the angle signal.

  The image sensor 104 photoelectrically converts a subject image formed by the imaging optical system M or the attachment optical system A and the imaging optical system M. The image movement detection means 105 determines in which direction the image has moved from the image information from the image sensor 104. The image movement detection unit 105 is generally a second movement detection unit that detects a motion vector of an image by comparing a pair of images with a time difference.

  The processor (CPU) 106 functions as a movement direction determination unit that acquires the detection result of the camera movement detection unit 103 and determines the movement direction of the digital camera 100. Next, the processor 106 functions as a movement direction comparison unit that compares the movement direction by the fine movement of the digital camera 100 with the movement direction of the output image based on the results of the movement direction determination unit and the image movement detection unit. Next, the processor 106 functions as an image processing unit that inverts or rotates the output image signal by processing the output of the image sensor 104. Further, the processor 106 also functions as a control unit that controls the image processing unit by comparing the outputs of the camera movement detection unit 103 and the image movement detection unit 105. The processor 106 also functions as image output means for outputting the image processed image to the liquid crystal monitor 101b or a storage medium (not shown). Note that the posture detection unit 102 and the image rotation unit of the processor 106 are not essential, and are used if necessary to improve the recognizability of the output image during vertical and horizontal shooting.

  FIG. 4 is a flowchart of image processing executed by the processor 106. In the figure, “S” means a step. Note that the subject image is in an inverted state in the initial state, and the horizontal position is the reference for the digital camera 100.

  First, when image processing starts, the processor 106 detects the current posture (S1). Next, the processor 106 detects the moving direction of the camera and the moving direction of the image by fine movement caused by camera shake (S2). Next, the processor 106 determines whether or not the pan movement direction of the camera matches the image movement direction (S3). If the processor 106 determines that they match (Yes in S3), the processor 106 performs a horizontal reversal process on the image (S4).

  On the other hand, if the processor 106 determines that they do not match (No in S3) or after S4, it determines whether or not the camera tilt (vertical) movement direction matches the image movement direction (S5). . If the processor 106 determines that they match (Yes in S5), it performs an upside down process of the image (S6).

  If no in S5 or after S6, the processor 106 uses the result of S1 to determine whether the camera is in the vertical position (S7), and if so (Yes in S7), rotate the image. Processing is performed (S8). If NO in S7 or after S8, the processor 106 outputs the image information (S9) and ends the process.

  Note that this flow is an example, and the inversion and rotation of the image may not be performed every time the panning or tilting direction is determined. For example, necessary information for processing may be stored according to the determination result at each stage, and the stored information may be used to invert and rotate the image collectively before final image information output processing.

  In general, if the movement of an image is detected from the detection of a motion vector of the image sensor 104, it takes time, and the detection delay of an angle detector such as a vibration gyroscope is small. Become. Stable determination can be performed by delaying the output of the camera movement detection means 103 to match the detection timing and extracting a movement frequency (for example, 1 to 2 Hz) to be compared using a known band pass filter (BPF). .

  FIG. 5 is a block diagram of the control system showing this state. The outputs of the camera movement detection means 103a in the pan direction (P) and the camera movement detection means 103b in the tilt direction (t) are delayed through the delay means 107a and b, respectively, and then input to the BPFs 108a and 108c. The delay means 107a and b have a function of providing a low-pass filter, an integration circuit, or a recording time difference for a predetermined time, and delay the outputs of the camera movement detection means 103a and 103b. On the other hand, the outputs of the pan-direction image movement detection means 105a and the tilt-direction image movement detection means 105b are input to the BPFs 108b and 108d without any delay means. Due to the delay means 107a and b, the detection timing of the camera movement detection means 103 coincides with the detection timing of the image movement detection means 105. The BPFs 108a to 108d cut unnecessary noise. The frequency band extracted by the BPF is set to a main band of camera shake such as 5 Hz.

  Reference numerals 109a and 109b denote differential detection means for obtaining the output difference between the BPFs 108a and 108b and the output difference between the BPFs 108c and 108d. When the output difference is almost zero, the output is zero, and when the output of the camera movement detection means 103 and the output of the image movement detection means 105 are reversed (when the attachment optical system A is attached), the output is doubled. 109c and 109d are known window comparators, which output L when the output of the differential detection means 109a and 109b is almost zero, H when the output is double, and HL when the output is intermediate, and input a signal to the processor 106. To do. The differential detection means and the window comparator may be part of the processor 106.

  The outputs of the window comparators 109c and 109d are divided into four types.

  When the window comparators 109c and 109d are both L, the attachment optical system A is not mounted, the subject image is upright, and the processor 106 does not perform image processing.

  When both the window comparators 109c are H, the attachment optical system A is mounted, and the subject image is upside down and left and right, so the processor 106 inverts the image both vertically and horizontally.

  When the window comparator 109c is L and the window comparator 109d is H, the attachment optical system is mounted, and the subject image is reversed left and right, so the processor 106 inverts only left and right.

  When both of the window comparators 109c and 109d are HL, the attachment optical system A is mounted, the subject image is in the vertical position rotated 90 degrees, and the processor 106 rotates the image direction 90 degrees to the right.

  As described above, when the attachment optical system A is connected to the photographing optical system, the output image can be automatically set to the normal position image without performing means for transmitting the connection state or manual switching.

  The optical device can be applied to an imaging device. The imaging device can be applied to imaging a subject.

100 Digital camera (imaging device)
101a Housings 103, 103a, 103b Camera movement detection means (first movement detection means)
104 Image sensors 105, 105a, 105b Image movement detection means (second movement detection means)
106 Processor A Attachment optical system (imaging optical system)
M Shooting optical system

Claims (6)

A taking optical system for forming a subject image;
An image sensor that photoelectrically converts a subject image formed by the imaging optical system;
An optical device including an imaging optical system added to the imaging optical system is detachable, and a housing that houses the imaging optical system and the imaging element;
Image processing means for processing the output of the image sensor;
First movement detecting means for detecting movement of the casing in a pan movement direction and a tilt movement direction;
Second movement detection means for detecting an image movement direction which is a movement direction of the subject image based on an output of the imaging element;
Control means for controlling image processing including inversion or rotation by the image processing means by comparing outputs of the first movement detecting means and the second movement detecting means;
Have
The control means includes
When it is determined that the pan movement direction of the casing detected by the first movement detection unit matches the image movement direction detected by the second movement detection unit, the image processing unit The output image signal obtained from the output is reversed left and right,
When it is determined that the tilt movement direction of the housing detected by the first movement detection unit matches the image movement direction detected by the second movement detection unit, the output image signal is output by the image processing unit. An imaging device characterized in that it is turned upside down. The imaging optical system includes a reflecting member that deflects an optical path, and a reflecting member moving unit that inserts and retracts the reflecting member into the optical path,
When the reflecting member moving means captures an image with the reflecting member inserted in the optical path, the left and right of the subject image are reversed,
The imaging apparatus according to claim 1, wherein when the reflecting member moving unit captures an image with the reflecting member retracted from the optical path, the subject image is vertically and horizontally reversed.   The imaging apparatus according to claim 1, wherein the photographing optical system performs even-numbered imaging. Delay means for delaying the output of the first movement detection means;
Comparison means for inputting the output from the delay means and the output from the second movement detection means;
Further comprising
The imaging apparatus according to claim 1, wherein the control unit acquires an output of the comparison unit. It further has posture detecting means for detecting the posture of the housing,
5. The imaging apparatus according to claim 1, wherein the control unit controls rotation of the output image signal by the image processing unit based on an output of the posture detection unit. A photographing optical system that forms a subject image, an imaging device that photoelectrically converts a subject image formed by the photographing optical system, and an optical device that includes an imaging optical system that is added to the photographing optical system are detachable, and the photographing An image processing method for processing an output image signal obtained from the imaging device of an imaging device having an optical system and a housing that houses the imaging device,
When the pan movement direction of the housing and the image movement direction, which is the movement direction of the subject image, coincide with each other, reversing the output image signal;
When the image moving direction and Tilt movement direction of the housing are coincident, the step of vertically inverting the output image signal,
An image processing method comprising: