JPH06141147A - Electronic imaging device - Google Patents

Abstract

(57) [Summary] [Purpose] To monitor an image close to the captured image with a simple configuration. [Arrangement] Normally, the image pickup lens 2 stands by at a position in focus at an infinite point, and incident light is imaged on a focus screen 43 arranged at a position substantially in focus with respect to the image pickup lens 2. . At the time of image pickup, the image pickup lens 2 extends forward by a distance L. At this time, the line CCD 21 located at the position B2 separated by the distance L scans the object imaged on the imaging surface. As a result, at the time of monitoring with the viewfinder 3, it is possible to focus on the image formed on the focus screen 43 and monitor an image close to the captured image.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scanning type electronic image pickup device for picking up an image of a subject by performing spatial scanning using, for example, a line CCD.

[0002]

2. Description of the Related Art Recently, a scanning type electronic image pickup device (commonly called a stereoscopic copy device) for scanning an image of a subject by using a line CCD has been developed. In such a case, the imaged character information is captured, and immediately printed out and output. Unlike an electronic blackboard, the use of an electronic image pickup device makes it possible to print the character information on an ordinary blackboard, which is extremely convenient.

In the conventional electronic image pickup apparatus using spatial scanning,
An object of interest is imaged and monitored on a focus screen through an optical system having a lens, and this object is electronically imaged and recorded by moving a line CCD.

Actually, the subject imaged on the focus screen is checked by looking through the viewfinder. The confirmation in this case is, for example, whether or not the subject is within a predetermined area where the image can be picked up. It is not to accurately focus the subject. For example, if the subject is at a short distance instead of the infinity point, the line CCD moves to the imaging position after the subject is captured by the viewfinder (after the image monitor), and the focus is changed from the infinity point. Suitable for close range. afterwards,
An image is taken by the line CCD after the subject is in focus.

[0005]

By the way, in the conventional electronic image pickup apparatus, in order to shorten the operation time, the image pickup lens is focused during the movement of the line CCD. However, there was a problem that the image close to the captured image could not be monitored when the monitor was not in focus. On the other hand, in order to eliminate such drawbacks, a complicated mechanism is required, and thus there has been a request for cost reduction in the past, and there has been no one that can monitor an image close to a captured image with a simple configuration.

[0006] Therefore, an object of the present invention is to provide an electronic image pickup device which has a simple structure and can monitor an image close to a picked-up image.

[0007]

In order to achieve the above object, an electronic image pickup apparatus according to the present invention confirms a subject imaged on a focus screen by an optical system with a viewfinder and images the subject with an image sensor. In the electronic image pickup apparatus for recording, the image forming surface of the focus screen and the image pickup surface of the image sensor are arranged so as to be offset from each other in the light incident direction.

In a preferred embodiment, the optical system is configured so as to move by a predetermined amount along the incident direction of light when taking an image.

[0009]

In the present invention, the image forming surface of the focus screen and the image pickup surface of the image sensor are arranged at different positions along the incident direction of light, and, for example, the image pickup lens is normally on standby at a position in focus at the point at infinity. The incident light is focused on a focus screen (focus plate) arranged at a position substantially in focus with respect to the position of the image pickup lens. At the time of image pickup, the image pickup lens moves by a predetermined amount (for example, is projected forward), and at the same time, the image pickup element receives light at a position different from the focus screen and scans the imaged subject. Therefore, at the time of monitoring with the viewfinder, it is possible to focus on the image formed on the focus screen, and it is possible to monitor an image close to the captured image with a simple configuration.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an external view of an electronic image pickup apparatus (commonly called a stereoscopic copy apparatus) according to the present invention. In FIG.
Reference numeral 1 denotes an electronic image pickup device, which has a rectangular parallelepiped shape of a certain size and is miniaturized, for example, to be convenient for carrying. An imaging lens 2 is arranged on the front side of the electronic imaging device 1. A viewfinder 3 and an operation unit 4 are arranged on the operation surface side of the upper surface of the electronic image pickup apparatus 1. The viewfinder 3 is a part where the imager looks into the subject when determining the range of the subject, and the subject imaged on the focus screen (see FIG. 3) through the imaging lens 2 is It can be seen from this viewfinder 3. It should be noted that AF is performed on the optical axis that passes through the viewfinder 3 from the imaging lens 2.
(Auto focus mechanism) and one-dimensional image sensor (line CCD) are built in.

The operation section 4 is a section for performing various operations necessary for image pickup, and is composed of, for example, a sheet switch, and can perform operations such as "start", "image pickup", and "print". A printer unit 5 is arranged beside the electronic image pickup apparatus 1, and the printer unit 5 prints and outputs the subject image formed on the image pickup surface by thermal transfer.

FIG. 2 is a block diagram showing the internal structure of the electronic image pickup apparatus 1. In FIG. 2, a line CCD (corresponding to an image pickup device) 21 in which elements are vertically arranged is movably arranged behind the image pickup lens 2, and a line CC is provided.
D21 has a function as a one-dimensional image sensor,
An image for one screen is read by moving in the image formation range of the imaging lens 2 in the lateral direction (arrow direction). The line CCD 21 is sequentially moved along with the horizontal movement.
The video signal output from the device is amplified by the preamplifier 22 and the gain is adjusted to be constant by the AGC amplifier 23 so that the contour of the image is enhanced and corrected.

The video signal output from the AGC amplifier 23 is subjected to a shading correction circuit 24 to correct the brightness of the central portion and the peripheral portion of the image, and then subjected to gradation control and binarization circuit 25 for gradation control. Binarized, 2
The binarized video signal is used for pixel enlargement control and image memory 2
6 is input. The pixel enlargement control and image memory 26 performs processing such as enlargement control of the pixels of the input video signal and storage of the image in the internal image memory.

The operations of the AGC amplifier 23, the gradation control / binarization circuit 25, the pixel enlargement control and the image memory 26 are controlled by a controller 30. The controller 30 is constituted by, for example, a microcomputer, and each of the above circuits 23. , 25, and 26, a drive signal for controlling scanning of the line CCD 21 is output to the motor control and drive circuit 31 according to a program described later, and a control signal is output to the thermal head control circuit 32.

The motor control and drive circuit 31 is line C
A CCD moving motor 33 for driving the CD 21 laterally,
A lens moving motor 34 for driving the image pickup lens 2 in the optical axis direction for focusing, and particularly for moving the image pickup lens 2 by a predetermined amount along the incident direction of light at the time of image pickup, and a printer. A feed motor 35 that rotationally drives a roller (not shown) in the section 5 is controlled. The rollers of the printer unit 5 feed and drive the thermal paper P. Further, the line CCD 21 is driven by the charge transfer clock in order to transfer the charges corresponding to the amount of light converted by the line CCD 21.

The thermal head control circuit 32 controls the thermal head drive unit 3 based on the position control signal output from the controller 30, the pixel enlargement control and the printer head control signal output from the image memory 26.
Control 6 When the thermal head drive unit 36 operates according to the input control signal,
The line C is attached to the thermal paper P that is driven by the roller.
The image of one screen when the CD 21 is moved laterally once is thermally transferred.

FIG. 3 is a view showing the main mechanism of the optical system. In FIG. 3, reference numeral 41 denotes an image pickup lens unit, and the image pickup lens unit 41 includes the image pickup lens 2 and a support member 42 that movably supports the image pickup lens 2. The image pickup lens 2 is normally supported by a support member 42 at a position A1 in the figure when a subject is confirmed by the viewfinder 3, and at the time of image pickup, a predetermined amount (a distance L ) Only to be driven. Further, when confirming the subject, the imaging lens 2 returns to the position A1 again.

A line CCD 21 is movably arranged behind the image pickup lens portion 41 along the light incident direction, and a focus screen (focus plate) 43 and an LCD 44 are sequentially arranged behind the line CCD 21. Line C
The CD 21 stands by on the image pickup surface deviated from the incident axis of light when confirming a subject, and moves at the time of image pickup in the vertical direction toward the image pickup surface shown in the drawing.
Such movement of the line CCD 21 is performed using, for example, a motor or a solenoid.

The focus screen 43 is the imaging lens 2
A light image incident through the focus screen 43 is formed, and in the image formed on the focus screen 43 at this time, an imageable range, horizontal lines, vertical lines, and the like are visible on the focus screen 43 by the LCD 44. The focus screen 43 is usually at a position A which is substantially in focus with respect to the imaging lens 2 which is normally focused at the point at infinity.
The line CCD 21 is arranged at a position B2 which is separated from the focus screen 43 by a predetermined amount (a distance L in this embodiment) forward (pointing to the light incident side) on the optical axis from the focus screen 43. . The focus screen 43
The LCD 44 is fixed and does not move.

A mirror 45 is arranged behind the focus screen 43 and the LCD 44 along the light incident direction at an angle of 45 ° with respect to the optical axis.
Is the optical image formed on the focus screen 43 at 45 °
Only the direction is changed and the light is reflected toward the viewfinder 3.
The viewfinder 3 is fixed by the finder support 46. Therefore, the focus screen 43
The optical image formed on the image can be viewed through the viewfinder 3.

Description of Operation Next, the operation of this apparatus will be described. (I) At the time of image formation At the time of image pickup, first, a subject (for example, character information on a blackboard) is confirmed through the viewfinder 3. At this time, the image pickup lens 2 is at the position A1 in FIG. 3, and is normally on standby at a position where the point at infinity is in focus. On the other hand, at this time, the line CCD 21 is on standby on the imaging surface off the optical axis.

Therefore, since the focus screen 43 is in a position substantially in focus with respect to the position A1 of the image pickup lens 2, the incident light from the subject forms an image on the focus screen 43 through the image pickup lens 2, and the image pickup range at this time is obtained. Is confirmed by the LCD 44. The optical image of the subject formed on the focus screen 43 is reflected by the mirror 45.
It is reflected by and is changed in direction by 45 ° and reaches the viewfinder 3. Therefore, the subject that is substantially in focus is visually recognized through the viewfinder 3. As a result, an image close to the captured image can be monitored from the viewfinder 3.

(II) At the time of imaging When the subject is confirmed and the step of imaging is completed, the imaging lens 2 extends forward from the position A1 to the position B1 in FIG. 3 by a distance L. This distance L is set to a frequently used feed amount. At the same time, line CCD
21 is the same distance L forward from the focus screen 43
The image pickup surface at the position B2 which is separated from the position is moved in the vertical direction toward the drawing.

In this case, since the subject is substantially in focus between the image pickup lens 2 already at the position A1 and the focus screen 43 already at the position A2, the image pickup lens 2 is moved forward by the distance L at the time of image pickup. Feeding out, line C
Even if the CD 21 is arranged at a position separated from the focus screen 43 by the distance L, the focus state of the subject does not change. That is, an image is formed on the line CCD 21 in a state in which the subject is substantially in focus. After that, the line CCD 21 moves in the horizontal direction to transfer the electric charge of the formed subject image, and electronically captures a two-dimensional captured image and finally prints it out. Instead of moving the imaging lens 2 forward by the distance L, focus may be adjusted by autofocus. Since the mechanism of the present embodiment only drives the movement of the image pickup lens 2 and the line CCD 21, it has the effect of requiring a simple configuration.

Although the above embodiment is an example in which the optical axis is changed in direction by 45 ° by a mirror, the present invention can be applied even to a linear optical system without bending the optical axis to the viewfinder. It is possible. Further, in the above embodiment, the distance L between the image pickup surface and the image formation surface is set from the beginning, but it is stored as the distance measured by autofocus, and the distance L is set according to the frequency and the focus screen is set to a motor or the like. You may change by moving with.

[0026]

According to the present invention, it is possible to focus an image formed on a focus screen during monitoring by a viewfinder, and it is possible to monitor an image close to a picked-up image with a simple structure.

[Brief description of drawings]

FIG. 1 is an external view of an embodiment of an electronic imaging device according to the present invention.

FIG. 2 is a block diagram showing an internal configuration of the electronic image pickup apparatus of the embodiment.

FIG. 3 is a diagram showing a main mechanism of an optical system of the same example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electronic imaging device 2 Imaging lens 3 Viewfinder 4 Operation part 5 Printer part 21 Line CCD (imaging element) 30 Controller 31 Motor control and drive circuit 33 CCD moving motor 34 Lens moving motor 35 Feed motor 41 Imaging lens part 42 Supporting member 43 Focus screen (focus plate) 44 LCD 45 Mirror 46 Viewfinder support

Claims (2)

[Claims] 1. An electronic image pickup apparatus for confirming a subject imaged on a focus screen by an optical system with a viewfinder, and capturing and recording the subject by an image sensor, comprising: an image forming surface of the focus screen; An electronic image pickup device, characterized in that the image pickup surface of the sensor is arranged so as to be displaced in the light incident direction. 2. The electronic image pickup apparatus according to claim 1, wherein the optical system is configured to move by a predetermined amount along a light incident direction during image pickup.