JPS63210828A - Image input device - Google Patents

Abstract

PURPOSE:To permit easy checking of whether a three-dimensional object is within a focusing range of the video of a subject or not by using a means for displaying the focusing range of the video of the subject to be imaged by an imaging lens. CONSTITUTION:The point B on an image pickup side exists by the front side depth X1 of field calculated on the optical axis L in the focus position A on the optical axis L parted by from the CCD face of the image pickup plane 7 by the focus distance S read from a focus position mechanism of a lens part 8. The point C on the subject side on a stage 2 exists similarly by the rear side depth X2 of field on the optical axis L from the focus position A. The distance range from the point C to the point B is accordingly the focus range. The No.3-No.9 of the LEDs of the display elements 9 existing in the distance range from the point C to the point B measured on the optical axis from the stage 2 are made to emit light. The focus range display device is provided in such a manner. Judgement of whether the part desired to be projected of the subject is in the focus range or not is thereby confirmed without having a need for viewing a fine monitor.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to an image input device, and particularly to a focusing box display device for an image input device.

(Prior Art) (a) A conventional image input device is, for example, filed by the present applicant in Japanese Patent Application No. 176083/1983.

Conventionally, with image input devices, the only way to judge whether or not what you want to display is within the focus range is by looking at the image displayed on the monitor. A separate and detailed monitor was required.

(b) Also, even if the lens is equipped with an autofocus mechanism, when a three-dimensional object is projected, not all parts of the three-dimensional object will be within the focus range, so it is difficult to correct it. I still had to look at the monitor and make adjustments.

(c) Furthermore, for example, when the subject to be photographed on the stand is a thick book, it is necessary to focus more carefully than when the subject is thin.

(Problems to be Solved by the Invention) 1. In other words, in common with conventional devices, an in-depth monitor is required to determine the in-focus state, and this is used to determine the in-focus state. There is a problem in that it is a troublesome task to determine the state of focus or: Jj4i7i.

(Objective of the Invention) This invention was made to solve the following two problems, and the focus range can be determined by the focus range display device of the image input device without looking at the monitor screen. It is an object of the present invention to provide an image input device for easily checking whether a three-dimensional object is within a certain range.

Means for Solving Problem C] Therefore, in the image input device according to the present invention, a
'B, an image input device equipped with an imaging lens that forms an image of the object on the imaging surface of the first stage of imaging that converts the image information of the object on stage 1- into electric No. 15; The above objective is achieved by providing a means for displaying the in-focus range of an image of a subject.

(Function) With the above configuration and the device that displays the focus range, it is possible to judge whether or not there are people in the focus range in the area where you want to display the subject by looking at a fine monitor. It can be easily confirmed even if it is not present.

(Embodiment) An embodiment of the present invention will be described above with reference to FIGS. 1 to 3.

In the figure, l is the subject, for example, the original to be read and photographed,
It is a tree, and 2 is a mounting table on which the subject is placed. Reference numeral 3 denotes a camera which is an imaging means for converting video information of the front subject 1 into an electrical signal. The lens unit 100 is attached to the camera 3.

The upper surface of the a-mounting stand 2 is usually achromatic or gray, but if it is white.

There is a risk that the amount of light received by the light source conversion (not shown) in the camera 3 will be too large and the output will become saturated, making it difficult to adjust the white balance properly, so it is best to keep the color gray with low reflection. desirable. Further, this surface is a diffuse reflection plate to prevent diffusely reflected light from entering the camera 3. 5 is a superposition support member integrated with the horizontal support part 4, and 6 is a power switch. 7 is this camera 3
The imaging surface 8 is a lens section for forming an image on the imaging surface 7. Reference numeral 9 denotes a display element which is a means for displaying a focusing range in which LEDs are arranged vertically.

The lens unit 8 includes a focus position detection mechanism 10a that generates an electric signal representing the focus position from the amount of rotation of a focus ring (not shown). TA! An aperture value detection mechanism Job and a focal length detection mechanism 10c are added that convert s into electrical signals, respectively, and extract the focal length Ill, F value, and distance data of the lens.
A stage 10 is constructed.

When the power switch 6 is turned on, the lateral depth of field
I, rear depth of field X2. An electric signal is manually input to the calculation mechanism 11, and calculations are performed using the following equations (1) and (2) from data on the diameter of the minimum circle of confusion stored in advance. .

Here, U is the object distance which is distance data, f is the focal length, F is the aperture value, S is the diameter of the circle of least confusion, and Xi calculated using equation (1) is the surface side depth of field, X2 calculated using equation (2) is the rear depth of field.

As shown in FIG. 3, which is a block diagram for explaining calculation and display of a focusing range according to an embodiment of the present invention, the focusing range calculated by the means 11 for calculating the focusing range shown in FIG. Based on the calculated values of XI and X2, the display element 9 displays
All LEDs between the positions where you jumped will be lit.

FIG. 2 is an explanatory cross-sectional view showing an example of display of the focusing range according to an embodiment of the present invention, in which 7 is the imaging plane and A is the lens section 8.
This is the focus position on the optical axis that is offset from the CCD surface of the imaging surface 7 by the focus distance IIS read from the focus position 18 mechanism 108. B is a point on the imaging side from the focus position on the optical axis by the front depth of field calculated above x 1. Similar to point B, point C is from focus position A to optical axis LL, rear depth of field x straddle mounting table 2.
This is the point on the subject side of the image.

() Therefore, the distance Il from point C to point B! Since the range is the focusing range IJtl, from the mounting table 2 to the optical axis, (1:all !Jli from point C to point Bt
The LEDs N003 to No.9 of the display element f-9 are made to emit light.

The in-focus range is displayed by repeatedly and continuously performing the series of calculations and processes described in -1- above.

When using the image input device, it goes without saying that the position of the subject or the distance a adjustment song must be adjusted so that the subject to be photographed falls within the range indicated by the ED.

According to one embodiment of the invention, the focal length of the lens is 7g! ,
One stage for extracting F value and distance data is 10! , ζ point vl! A distance detection mechanism 10c, an aperture value detection mechanism 10b, a focus position detection mechanism 10a, and a front depth of field x1. Back depth of field x2. calculation mechanism 11;
By setting the display element (-9), which is a means of displaying the focus range, it becomes easy to check whether the part of the subject's body that you want to see is within the focus range, so the image The user of the input device can now adjust the focus without using a monitor.

In one embodiment of the present invention, an ED is used for the display portion of the display means, but other light emitting elements, liquid crystals, etc. may be used.

(Other Embodiments) In the above embodiment of the present invention, a case has been described in which the 1q position where the imaging lens is focused is displayed by switching the lighting state of the display element 14. An example of a field in which lenses are formed into a so-called zone focus will be described with reference to FIGS. 4 and 5.

The same/corresponding components as in FIGS. 1 to 3 of one embodiment of the present invention are represented by the same reference numerals, and duplications are omitted in the description.

Reference numeral 101 denotes a focusing lens in the lens unit 100;
Reference numeral 2 denotes a potentiometer, which consists of fixed terminals a, b, and a movable end Fc. The movable end 'f-C is linked with a focusing lens 101, and when this lens 101 moves in the direction of the arrow far in the figure to focus on a distant object, it moves in the direction of the fixed Qafa. When focusing on a nearby object, the object moves in the opposite direction toward the fixed terminal. Also, electrically, the fixed end %a is the power supply V
CC and the fixed end terminal are connected to ground, and when the lens 101 moves in the direction of the arrow far, the potential of the movable terminal C becomes high, and when it moves in the direction of the arrow near, the potential of the movable terminal C becomes VD. ing.

103 is a motor for driving the lens 101;
One terminal a is connected to ground, and the other end T-b is connected to an output terminal C of an amplifier 104, which will be described later.

104 is an amplifier, a is its non-inverting input terminal, and a is the input terminal of the potentiometer 102! It is connected to #lJ end fC, and b is its inverting input Kf.

D, D,, D2 is the focal point R'r! By dividing the n region into three, for example, a focus adjustment position is set in advance (focal point: distance m from the imaging surface 7 of the AwI lens 101). S, S+, S2 are the depths of field at the distances, D, , D2, and the distances, D, and the distances, D + ,
Between D2 and D'.

Since it is set to be continuous at Dlo, the distance in focus is from D to D2°, and the distance Ho 2 ' is the closest position. 12 is a thick piece of wood, such as an encyclopedia, which is the object to be read.

Regarding Figure 5, there are some common parts.

The explanation will be given assuming that the point of conflict between the two is 1.

The inverting input QQ F b of the amplifier 104 is a switch! 60
Connect the end f d of the switch to the point where the ground and 'It gVcc are divided by resistors 161, 162, 163, 164! 60 terminals a, b, and c. The respective potentials of these terminals a, b, and c are! ! , point J4 node is distance D2. Potentiometer 1 when set to D,,D
The values of the resistors 161, 162, 163 and 164 are set to be equal to the potential of the 11fljjJ terminal/-C of 02. Also, a [-d of the switch 160 is the operation knob 13
is connected to either end f-a, b, or c by moving.

One end of the resistor 171 is connected to the power supply Vcc, and the other end is connected to the switch 1.
It is connected to terminal d of 70. 172, 173, and 174 are means for displaying the focusing range, and are placed at positions corresponding to distances, D, and D, as shown in Figure 4. , one end of each is connected to a switch 170
pant fa.

b and c, and the other ends are all connected to ground. In addition, terminal d is also linked to operation knob 13, and terminal a,
It is linked to either b or c. Furthermore, operation knob 1
3 can take three positions: near, middle, and far, and in each position, the switches 160 and 170 are connected between ends ra and d, between b and d, and between c and d. The focal length is @D2. D,, adjusted to D,
Display elements 172, 173, and 174 are displayed.

In actual operation, as shown in FIG. 4, when a thick tree 12 is placed on the mounting table 2, the distance is set by moving the operating knob 13 to the middle position using the position of the display element as a guide. The focus is adjusted to llID+ and the entire open page of tree 12 is in focus.

Further, for a typical thin document, the focus can be set on the a placement table 2 by moving the operation knob 13 far away, and further by moving the operation knob 13 closer according to the height of the object.

However, as mentioned above, even if focusing is done electrically or manually while looking at a monitor, it is a tedious process, difficult to adjust, and difficult to obtain the correct value. In another embodiment of the present invention, the focus adjustment area is divided into three and the focus is adjusted by focusing on the center of the three divided areas. ! #! lll
o, o r.

It can be said that it is effective to use the depths of field XI and X2 obtained by one embodiment of the present invention as the depth of field at D2. Also, when performing such control, the zone in focus is displayed! -) is displayed as ``4-'', which has the effect of making it easier to use.

In the other embodiment of this invention described in L, the focus adjustment area is divided into three parts, but 4! It goes without saying that the number of divisions can be increased or decreased depending on the distance of the stand, the position of the closest distance, the focal point of the lens, the lens diameter, the aperture diameter, etc.

As described above, according to another embodiment of the present invention, focus adjustment can be easily performed by dividing the focus adjustment area and focusing on the center of the divided area. There is an effect that it can be done.

(Effects of the Invention) As described above, according to the present invention, by attaching a focusing range display device, it is possible to judge whether or not the part of the subject to be photographed is within the focusing range using a fine monitor. Since this can be confirmed without looking at the image input device, the user of the image input device can now adjust the focus without using a monitor.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an image input device according to an embodiment of the present invention, FIG. 2 is a sectional view of the image input device, FIG. 3 is an explanatory diagram of calculation and display of the in-focus range IM, and FIG. The figure is a cut-away front view of another embodiment, and FIG. 5 is an explanatory diagram of the overall configuration. 1--------Original 2-----Place table 3---Camera 7---Imaging surface B, l O1---Lens 9, 172. 173. 174=・”aiF<element f
12... Book 100--Lens section, D+, D2 ""- Focus adjustment (tγ system S,
S+, S2 ""...Depth of field In each figure, the same reference numerals refer to 1-71-/K+.

Claims (3)

[Claims] (1) An image input device comprising an imaging means for exchanging image information of a subject on a mounting table into an electrical signal, and an imaging lens for forming an image of the subject on an imaging surface of the imaging means,
An image input device comprising means for displaying a focusing range of an image of a subject formed by the imaging lens. (2) The image input device according to claim 1, wherein the focusing range is based on data extracted by means for extracting focal length, F-number, and distance data of an imaging lens. (3) The image input device according to claim 1, wherein the display means displays a position corresponding to a range obtained by dividing a focus adjustment range in which focus is adjusted by moving the imaging lens.