JPH04150674A - Image pickup device - Google Patents

Abstract

PURPOSE:To prevent the failure of photographing by controlling a focus frame generating circuit outputting a focus frame signal for indicating a certain area in a screen decided by a gate circuit according to the discriminated result of the attaching and detaching state of a lens unit to a main body unit of a camera. CONSTITUTION:The attaching and detaching state of an lens unit LU to a main body unit CU a camera is discriminated According to the discriminated result, a focus frame generating circuit 41 outputting the focus frame signal for indicating the certain area in a screen decided by a gate circuit 42 is controlled. Thus, it is possible to know the attaching and detaching state of the lens unit LU easily, to prevent the failure of the photographing, and not to generate futile worry and anxiety to a photographer.

Description

[Detailed Description of the Invention] (Industrial Application Field) The invention relates to an imaging device such as a video camera, particularly an imaging device in which a lens unit is replaceable with respect to a camera body unit. It is.

[Conventional technology]

Traditionally, video cameras configured as camera-integrated VTRs generally do not have interchangeable lenses, and unlike still cameras that use silver-halide film, it is not easy to take ambitious shots or wide-angle shots. The scope is narrow. However, recently, integrated VTRs with interchangeable lenses have been proposed, and they also have autofocus (autofocus) functions and auto iris (auto exposure) functions.
It has not yet reached the point where it is fully functional.

Therefore, the inventors of the present application have proposed a video camera with interchangeable lenses, in which a lens unit with a built-in photographic lens and an aperture is detachably and replaceably attached to a camera body unit with a built-in image sensor. We are proceeding with the development of In this video camera, the camera body unit and the lens unit are each equipped with a control device consisting of a microcomputer, etc., and when the two units are combined, the control device in both units is connected via a data transmission path (communication line). are now connected to each other. Then, in the camera body unit, the field brightness is detected from the output of the image sensor, and based on the field brightness, the control device in the camera body unit selects the exposure mode. j′ calculation, and transmits the exposure calculation result to the control device in the lens unit, and the control device in the lens unit determines the aperture opening amount based on the exposure calculation result, and applies the aperture opening amount to the determined opening amount. The aperture drive means is driven accordingly. Further, the field brightness signal in the camera body unit is band-limited by passing it through a plurality of band pass filters, and the focus calculation of the control device in the camera body unit is performed based on this band-limited signal, and the calculation result is is transmitted to the control device in the lens unit, and the control device in the lens unit determines the direction and speed of the focus motor based on the ablation calculation result, and operates the focus drive means according to the determined direction and speed. It is designed to be driven.

[Invention or problem to be solved]

By the way, in an imaging device with interchangeable lenses that has an exposure control system and a focus control system as described above, if the lens unit is not properly attached to the lens unit or camera body unit for some reason when attaching or detaching the lens unit, there is Communication may not be carried out normally, and sufficient functions may not be obtained.For example, the aperture may remain closed or the focus may not be adjusted automatically, which may lead to failure in shooting. There is a problem with not being able to take pictures.

The present invention was made by focusing on these problems.
To provide an imaging device in which the attachment/detachment state of a lens unit can be easily known, failure in photographing can be prevented, and a photographer does not have unnecessary worry or anxiety.

[Means to solve the problem]

The imaging device of the present invention has a camera body unit equipped with an image sensor, and a lens unit that is detachably attached to the camera body unit and whose focus can be adjusted. a determination means, a focus circuit for performing the focus adjustment in an arbitrary area within the imaging screen, a focus frame generation circuit for outputting a focus frame signal for displaying the area, and the focus frame generation circuit is attached and detached. The apparatus is equipped with a control device that performs control according to the determination result of the determination means.

[Effect]

In the imaging device of the present invention, the attachment/detachment determination means determines whether the lens unit is attached or detached from the camera body unit, and the control means displays a certain area within the screen determined by the Kate circuit according to the determination result. control a focus frame generation circuit that outputs a focus frame signal for

(Embodiment) Fig. 1 is a block diagram showing the circuit configuration of an imaging device according to an embodiment of the present invention, showing the main parts of a Hiteo camera with interchangeable lenses. Main unit, LU is this camera main unit CU
Both units 1-cC+ and LtJ are mechanically and detachably connected by a known mount part MT in which mutual pressure contact terminals are arranged, and the lens unit 1-cC+ and LtJ are connected to each other in the lens unit LU via the mutual pressure contact terminals. A microcomputer (hereinafter referred to as a lens microcomputer) 14 that is a control device
A data transmission path 39 for serial data transmission is formed between the camera body unit CU and a microcomputer (hereinafter referred to as camera microcomputer) 34 which is a control device within the camera body unit CU.

In addition to the above-mentioned lens mic 14, the lens unit 'L Ll includes an aperture 2. Aperture encoder 3 that detects the aperture opening amount (aperture value)
．． Focus motor (M) for adjusting focus 4. A focus encoder that detects the focus5. A motor drive circuit 6 for driving the focus motor 4. Aperture drive circuit that drives the aperture 2 7. D/A converts digital signals to analog signals
A converter 89 and an A/D converter 10 for converting an analog signal into a digital signal are provided, and a lens microcomputer 14 is provided with a drive data circuit 11 for outputting the tribe data of the lens 1 and the lens 2, and a drive data circuit 11 for transmitting data. and a data transmitting/receiving circuit 12. Encoder conversion circuit 1
It is made up of 3rd grade.

On the other hand, in addition to the above-mentioned camera microcomputer 34, the camera body unit CU includes an image sensor 16, such as a CCD, into which the flux of photographing light that has passed through the lens 1 and the diaphragm 2 enters. A piezoelectric element 15 that vibrates this image sensor 16. Sample hold (S/H) that samples and holds the output signal of the image sensor 16
Circuit 17゜Camera signal processing circuit 18 which inputs the image signal output from this sample hold circuit 17 and outputs a signal and a color signal once. A blue generation circuit 19 outputs a blue color signal unrelated to the output signal (photographed video signal) of the camera signal processing circuit 18. A piezoelectric element drive circuit 21 for driving the piezoelectric element 15. An exposure circuit 24 for obtaining proper exposure from the output of the sample and hold circuit 17 and a focus detection circuit 27 for obtaining optimum focus from the output of the sample and hold circuit 17 are provided. and a photometry circuit 23, and the focus detection circuit 27 includes a plurality of BPFs (band pass filters) 25. It is comprised of a peak detection circuit 26 that samples and holds the output signal of the BPF 25 and performs peak detection, and a gate circuit 42 that performs focus adjustment in an arbitrary area within the imaging screen. Furthermore, this camera body unit cU has a
/D converters 30, 31. Attachment/disassembly switch (attachment/disassembly determining means) 35 for determining whether the lens unit LU is attached or detached from the camera body unit CU (here, it is determined whether or not it is normally attached). A microcomputer (hereinafter referred to as system microcomputer) 36 that controls the entire camera system; a battery 37 that is the main power source; A switching circuit (switching means) 38 for supplying driving power from this battery 37 to each part of the camera. Signal switching circuit 20 controlled by system microcomputer 36. An encoder (ENC) circuit 40 for outputting a decoded video signal and an EVF circuit 28 for monitoring the video on a viewfinder. A character generator circuit 29 that generates arbitrary character information and a focus frame generation circuit 41 that outputs a focus frame signal for displaying an area determined by the above-mentioned gate circuit 42 on the viewfinder are provided. The microcomputer 34 includes a data transmitting/receiving circuit 32. It is composed of a control calculation circuit 33 and the like.

In addition, the system microcomputer 3 of the camera body unit Ct+
Reference numeral 6 constitutes a control means that controls the focus frame generation circuit 41 according to the on/off signal that is the determination result of the attachment/detachment switch 35, and also supplies power from the battery 37 to the regulator (REG) power supply 43 of the lens unit LLI. Power is supplied from here to each power source.

Next, the operation will be explained.

When the lens unit LU or camera body unit CU is properly attached, the luminous flux of the imaging light that passes through the photographic lens 1 and the camera body 2 and enters the image sensor 16 is photoelectrically converted and becomes an image signal. is output. This image signal is passed through the sample hold circuit 17 to the camera signal processing circuit 1.
8, and after being subjected to comma conversion or the like in the circuit 18, the signal is separated into a color signal C and a luminance signal Yγ and taken out. These colors (g-signal C and luminance signal Yγ) are converted into decoded video signals by the encoder circuit 40 and output to the outside, and are also monitored by the EVF circuit 28 on the viewfinder.

Further, the luminance signal Y output from the sample hold circuit 17 is input to the exposure circuit 24 as described above, and is integrated there by the integration circuit 22. Then, photometry is performed by the photometry circuit 23, from which an appropriate photometry signal is output. After this signal is converted into a digital signal by the A/D converter 30, it is input to the camera microcomputer 340 control calculation circuit 33, where a predetermined exposure calculation is performed. Then, as a result of the calculation, an aperture control signal is output from the data transmission/reception circuit 32 of the camera microcomputer 34.
This signal is sent to the lens unit L via the data transmission line 39.
It is supplied to the lens microcomputer 14 of U. At this time, if the electrical connection between the lens knee unit LU and the camera body unit CU is stable, for example, the lens unit L
If a certain amount of time has passed since U and the camera body unit CU were attached to each other, if there is no abnormality or malfunction in the data transmission path 39, or if there is an abnormality in the power supply inside the camera body unit CU. If not, the lens microcomputer 14 calculates the aperture drive amount based on the aperture control signals sent from the camera microcomputer 34, and outputs the aperture drive signal obtained as a result of the calculation from the tribe data circuit 11. This signal is converted into an analog signal by the D/A converter 8 and then input to the aperture drive circuit 7, which drives the aperture 22. The amount of movement of the aperture 2 is detected by an encoder 3, and the detection signal is converted into a digital signal by an A/D converter 10 and input to a lens microcomputer 14. The encoder conversion circuit 13 in the lens microcomputer 14 then generates a signal representing the state of the aperture, and this signal is transmitted to the camera microcomputer 34 via the data transmission line 39.

Appropriate aperture control is performed through the above operations, and similar operations are performed for focus control.

That is, the luminance signal Y output from the sample hold circuit 17 described above is also input to the focus detection circuit 27 in order to obtain the optimum focus, and after being band-limited by a plurality of BPFs 25 here, the luminance signal Y is outputted by the gate circuit 42. and is input to the peak detection circuit 26. A proper focal voltage signal is output from the peak detection circuit 26, converted into a digital signal by the A/D converter 31, and then input to the camera microcomputer 34. In this camera microcomputer 34, a predetermined calculation is performed by a control calculation circuit 33, and focal voltage data obtained as a result of the calculation is inputted from the data transmission/reception circuit 32 to the lens microcomputer 14 via a data transmission path 39. . Furthermore, this data is sent to the data transmitting/receiving circuit 12 and the tribe data circuit 1.
1, it is manually inputted to the D/A converter 9, and here the analog (
After being converted into No. 8, it is supplied to the motor drive circuit 6, and the focus motor 4 is driven by kneading to control the focus. This focus state is detected by the focus encoder 5, and the detection signal is sent to the lens microcomputer 14.
is input. After the signal is converted by the encoder conversion circuit 13, the signal is transmitted to the camera microcomputer 34 via the data transmission/reception circuit 12 and the data transmission path 39.

Through the series of closed-loop operations described above, it is possible to perform appropriate aperture control and focus control in a video camera with interchangeable lenses.

Here, the above-mentioned operation is for the case where the lens unit LU or the camera body unit CU is normally attached, or the lens unit LU is detached from the camera body unit CU and some abnormality occurs in the data transmission path 39. For example, if there is a poor contact between the connection terminals of the lens unit LU and camera body unit CU, this information is immediately transmitted to the photographer in this embodiment. .

That is, the camera microcomputer 34 normally outputs a gate pulse to the gate circuit 42 in order to obtain the above-mentioned focal voltage signal within an arbitrary area within the screen of the viewfinder.
The gate circuit 42 uses the pulse signal to control the plurality of BPFs 2.
The signal is band-limited by 5. Then, the focus frame generation circuit 41 outputs the above-mentioned focus frame signal in order to cause the EVF circuit 28 to display the highlighted area on the 21 viewfinder. However, if the lens unit LLI is not properly attached, the information is input to the system microcomputer 36 by the attachment/detachment switch 25 and the camera microcomputer 34, and the output of the focus frame generation circuit 41 is stopped. At the same time, character information indicating that the lens unit LLI is not properly attached is output from the character generator circuit 29 to the EVF circuit 28, and this information can be conveyed to the photographer at a glance through the viewfinder.

In this way, when the lens unit LU is not installed properly, the focus frame disappears from the view finder and the character information is displayed, which clearly indicates that the lens unit LU is not installed properly. The situation can be communicated, and the photographer can easily know whether the lens unit Lυ is attached or detached. Therefore, failures in photographing can be prevented, and the photographer does not have to worry or worry unnecessarily. At this time, a desired display can be made using the blue generation circuit 19 and the like.

(Effects of the Invention) As described above, according to the present invention, the attachment/detachment state of the lens unit to the camera body unit is determined, and according to the determination result, the focus for displaying a certain area in the screen determined by the Kate circuit is determined. Since the focus frame generation circuit that outputs the frame signal is side-impeded, it is easy to know whether the lens unit is attached or detached, which prevents failures in shooting and causes unnecessary worry and anxiety to the photographer. There is an effect that there is no such thing.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention. CLl-...Camera body unit LIJ...
... Lens unit M T ---Mount section 1 ... Photographing lens 2 ... Diaphragm 15 ... Piezoelectric element 16 ... Image sensor 18 ... Camera signal processing circuit 19 --- Blue generation circuit 20 ... Switching circuit 22 ... Exposure circuit 27 ... Focus detection circuit 28 ...-E V F circuit 29...Character generator 5...
・Attachment/detachment switch (attachment/detachment determination means) 6...Microcomputer (control means 1...Focus frame generation circuit 2...Cate circuit

Claims (1)

[Claims] It has a camera body unit equipped with an image sensor, a lens unit that is detachably attached to the camera body unit and whose focus can be adjusted, an attachment/detachment determination means for determining whether the lens unit is attached or detached, and an attachment/detachment determination means for determining an attachment/detachment state of the lens unit; a gate circuit for performing the focus adjustment in the area, a focus frame generation circuit for outputting a focus frame signal for displaying the area, and a control for controlling the focus frame generation circuit according to the determination result of the attachment/detachment determination means. An imaging device characterized by being equipped with a device.