JPH0733494Y2 - Shooting condition recorder for electronic camera - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a photographing condition recording device for an electronic camera, which is capable of recording magnification information together with image recording when recording an image with the electronic camera. .

[Conventional technology]

Recently, in recording a still image, an electronic still camera, which converts an optical image formed on an image sensor such as a CCD into a video signal and records the video signal in a still video floppy, has become widespread. Further, a video camera using a magnetic tape as a recording medium has been widely used.

In such an electronic camera, there is an advantage that a recorded image can be immediately reproduced by a CRT monitor without performing development processing after recording, and a still video floppy or a magnetic tape as a recording medium can be repeatedly used. . Further, since such an electronic camera records an optical image as a video signal, it is easy to obtain various modulated images by adding signal processing at the time of reproducing the image. Utilizing these features of electronic cameras,
Electronic cameras have come to be used not only for recording growth of children and flora and fauna, but also for geographical measurement and current condition measurement at construction sites.

[Problems to be solved by the invention]

When an electronic camera is used for the purpose of such a measurement, it is usual to work to obtain the size and size of an object from an image during reproduction. However, when the image recorded by the conventional electronic camera is reproduced, the actual size of the object cannot be determined due to lack of information only with the image. Therefore, in the past, a scale was placed near the object to be measured for recording, or the distance from the camera to the object was measured at the time of image recording with a survey instrument, and the measured value was recorded separately. Work such as is required. However, such work becomes very complicated when there are many kinds of objects to be measured, or when recording is sequentially performed while changing the object distance, and the work efficiency is poor. there were.

[Purpose of device]

The present invention has been made in view of the above-mentioned drawbacks of the prior art. When the image is recorded, the photographing magnification information is recorded on the recording medium to easily determine the actual size of the object from the reproduced image. It is an object of the present invention to provide a photographing condition recording device for an electronic camera, which is capable of performing

[Means for solving problems]

In order to achieve the above object, the present invention provides a distance detecting means for detecting a distance from a photographing lens of an electronic camera to an image pickup element or a distance from the photographing lens to a subject, an output from the distance detecting means and a focus of the photographing lens. A magnification calculating means for calculating the photographing magnification from the distance is provided, and the photographing magnification calculated by the magnification calculating means is recorded on the image recording medium of the electronic camera.

[Action]

When the distance detecting means detects the distance between the taking lens and the image pickup element, the distance detecting means detects a so-called image distance b between the taking lens moved to the in-focus position and the image pickup element. Further, since the focal length f of this photographing lens is known in advance, the magnification calculation means calculates from the distance b and the focal length f as follows:
The photographing magnification M is calculated by the following formula.

The photographing magnification M calculated in this way is recorded on the recording medium via the recording head for image recording.

An embodiment of the present invention will be described below with reference to the drawings.

〔Example〕

In FIG. 1 schematically showing an example in which the present invention is applied to an electronic still camera, a taking lens 1 is provided in front of an image sensor 2 made of a CCD so as to be movable in an optical axis direction. A lens extension lens barrel 3 is fitted in the taking lens 1, and the lens extension lens barrel 3 is rotated by driving a motor 4. The drive of the motor 4 is controlled via the controller 6 and the driver 7.

An autofocus device 5, a sensor driver 8, a magnification calculator 9 and a ROM 10 are connected to the controller 6. As is well known, the autofocus device 5 photoelectrically detects a distance measurement signal corresponding to the subject distance, and inputs this to the controller 6. Then, the controller 6 supplies a drive pulse signal to the driver 7 in response to the distance measurement signal, and the motor 4 is driven by this.

The sensor driver 8 controls driving of the image sensor 2 in response to a clock pulse input from the controller 6.
The image sensor 2 converts an optical image formed on the photocathode by the taking lens 1 into an electric signal, and a signal processing circuit.
Output to 10. The signal processing circuit 10 performs signal processing on the electric signal from the CCD 2 and outputs it as a video signal to the recording circuit 11. The recording circuit 11 outputs a recording signal to the magnetic head 12 according to the input video signal, and the magnetic head 12 performs magnetic recording on the magnetic sheet 14 in the still video floppy 13.

As will be described in detail later, the magnification calculator 9 calculates the magnification M at the time of shooting from the distance data between the shooting lens 1 and the image sensor 2 and the focal length data of the shooting lens 1 stored in the ROM 15. Then, this is output as a digital code signal. The digital code signal for the magnification M is
It is output to the signal processing circuit 10 and the LCD driver 16. As shown in FIG. 2, the LCD driver 16 is a liquid crystal (LC) provided so that it can be observed from outside the body of the electronic still camera.
D) 17 is driven and the magnification M is digitally displayed by the digital code signal. The signal processing circuit 10 converts the digital code signal into a video signal for displaying a numeric character representing the magnification M or a bar code, and supplies this to the recording circuit 11. In addition, reference numerals 5a and 5b in FIG.
Indicates a light projecting portion and a light receiving portion used in the autofocus device 5, and reference numeral 18 indicates a finder.

The present invention is constructed as described above, and its operation will be described below.

After the unrecorded still video floppy 13 is loaded into the floppy holder of the electronic still camera, the viewfinder 18 is aimed at the subject and the shutter button 20 is pressed to the first stage. As a result, the light projecting section of the autofocus device 5
A light beam for distance measurement is emitted from 5a toward the subject, and the light reflected from the subject is incident on the light receiving unit 5b. As shown in FIG. 3, the autofocus device 5 detects a distance measurement signal corresponding to the object distance a from the taking lens 1 to the subject 21.

The distance measurement signal thus obtained is input to the controller 6. The controller 6 supplies the driver 7 with a number of drive pulses corresponding to the distance measurement signal, and when the motor 4 is driven by this, the lens feeding cylinder 3 rotates by an amount according to the distance measurement signal. By rotating the lens extension cylinder 3,
The taking lens 1 is extended from the reference position via a known helicoid. Of course, the amount of extension of the taking lens 1 corresponds to the distance measurement signal.

Data representing the number of drive pulses output from the controller 6 to the driver 7 is supplied to the controller 6. The number data of drive pulses corresponds to the amount of extension of the taking lens 1 from the reference position. Then, the number data of the drive pulses is compared with the data stored in the ROM 15, and is input to the magnification calculator 9 as the distance from the image sensor 2 to the taking lens 1, that is, the image distance b shown in FIG. . The ROM 15 has a focal length f of the taking lens 1.
Is also stored in the memory, and the controller 6 also sends the data of the focal length f to the magnification calculator 9.

When the image distance b and the focal length f of the taking lens 1 are obtained in this way, the magnification calculator 9 The magnification M is calculated by the equation (1) and is output to the signal processing circuit 10 and the LCD driver 16 as a digital code signal.
As a result, the magnification M is digitally displayed on the LCD 17.

After confirming the magnification display on LCD17, press shutter button 2
When 0 is pressed, the sensor driver 8 operates, the optical image formed on the image sensor 2 is electrically read by the taking lens 1, and its output signal is a signal processing circuit.
Supplied to 10. The signal processing circuit 10 includes an image sensor 2
The video signal is converted into a video signal and supplied to the recording circuit 11, and the video signal is magnetically recorded on the magnetic sheet 14 by the magnetic head 12. In this magnetic recording, a video signal for one frame is recorded on one track of the magnetic sheet 14.

By the way, the signal processing circuit 10 is provided with a magnification M from the magnification calculator 9.
A digital code signal representing is input. The signal processing circuit 10 also performs signal processing on this digital code signal, and when reproducing an image on a CRT, outputs it to the recording circuit 11 as a video signal such that the magnification M is digitally displayed at a predetermined position on the CRT screen. Therefore, the recording circuit 11 drives the magnetic head 12 based on the video signal for image recording and the video signal for magnification display, and these video signals are recorded on a common track of the magnetic sheet 14. Become. Then, the image recording for one screen of the image sensor 2 is completed, and the one-time recording is completed.

By applying the still video floppy 13 recorded in this way to the reproducing device, the recorded image can be reproduced on the CRT screen. At this time, the magnification M is digitally displayed at a predetermined position on the CRT screen. And
Since the image enlargement ratio after the image sensor 2 can be obtained in advance, the actual size can be determined from the display size of the object displayed on the CRT screen. In order to measure the size of the object displayed on the CRT screen, it is possible to specify and detect two points on the CRT screen with a light pen or the like.
By displaying it on the screen and reading it with a light pen as well, the actual size of the object can be automatically calculated.

In the case where a spare track is prepared on the magnetic sheet 14, if the digital code signal representing the magnification M is recorded on the spare sheet in sequence when the digital code signal representing the magnification M is recorded, the above-mentioned is not always possible. As described above, the image may be recorded on the image recording track. The autofocus device 5
Since it is possible to measure the object distance a to the subject, instead of calculating the magnification M from the image distance b and the focal length f of the imaging lens as described above, the object distance a and the focal distance f, or the object distance a The magnification M can also be calculated from a and the image distance b.

The present invention can be used not only in combination with an autofocus device, but also in an electronic still camera that is adapted to perform manual focus adjustment. In this case,
When the photographing lens 1 is manually set to the in-focus position, the set position is detected by a potentiometer or the like, the image distance b is determined by the signal from the potentiometer, and the same calculation processing is performed by the magnification calculation unit 9. Good. In addition to the electronic still camera described above, the present invention can be similarly applied to a video camera using a magnetic tape or a video disk as a recording medium. When a zoom lens is used as the taking lens 1, a signal of the focal length f that changes according to zooming may be detected by a potentiometer or the like.

[Effect of device]

As described above, according to the present invention, the photographing magnification is obtained from the lens position signal in the in-focus state and the photographing condition related to this magnification is recorded on the recording medium of the electronic camera. Without having to measure the distance to or to record the measurement result, you can immediately obtain shooting magnification information on the spot during image playback,
This makes it possible to correctly and easily determine and measure object distances and object dimensions.

[Brief description of drawings]

FIG. 1 is a schematic view showing an embodiment of the present invention. FIG. 2 is an external view of an electronic camera using the present invention. FIG. 3 is an explanatory diagram of an object distance or an image distance used for magnification calculation. 1 ... Shooting lens 2 ... Image sensor 5 ... Autofocus device 6 ... Controller 9 ... Magnification calculation unit 10 ... Signal processing circuit 11 ... Recording circuit 12 ... Magnetic head 13 ... Still video floppy 15 ... … ROM 17 …… LCD (for display).

Claims (2)

[Scope of utility model registration request] 1. An electronic camera in which a subject image is formed on an image sensor by a photographing lens, the subject image is converted into a video signal, and then recorded on a recording medium by a recording head. Distance detection means for detecting the distance from or the distance from the shooting lens to the subject,
Equipped with magnification calculation means for calculating the photographing magnification from the output from the distance detection means and the focal length of the photographing lens, the photographing magnification obtained from the magnification calculation means is converted into recording data and recorded by the recording head. An imaging condition recording apparatus for an electronic camera, which records on a medium. 2. A photographing condition for an electronic camera according to claim 1, further comprising a display for displaying the photographing magnification obtained from the magnification calculating means outside the body of the electronic camera. Recording device.