JPH0388561A - Image reader - Google Patents

Abstract

PURPOSE:To prevent beforehand the deterioration of an image and the damage of the device to be caused by abnormality by informing an operator of a fact that abnormality of an automatic control of a projection lens is detected. CONSTITUTION:A projection lens 1018 is returned to a reference position, a stepping motor 1014 is driven in the backward motion at every one pulse, the projection lens 1018 is moved backward until a limit switch 1019 is turned on, and subsequently, the stepping motor 1014 is driven in the advance direction at every one pulse, and the lens is advanced until the limit switch 1019 is turned off. In such a case, in the case the limit switch 1019 is not turned on, and the limit switch 1019 is not turned off, a control error message for urging a confirmation of the projection lens 1018 is displayed on a touch panel display 1101, and also, moving control of the projection lens 1018 is stopped. In such a way, an error state can be confirmed easily, and an immoderate lens moving operation can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image reading device for reading an image of a light-transmitting original such as a film.

[Conventional technology]

Manual (
When focusing (manually), place a white piece of paper on the projection surface (for example, the document table glass), illuminate the light-transmitting original with a lamp, project it onto the white paper, and manually adjust the projection lens while monitoring the projected image. It was moved by operation.

[Problem that the invention is trying to solve]

Therefore, in order to reduce the burden on the operator during manual focusing, we have developed a function that automatically controls the projection lens, which is the image forming means, near the focus position during manual focusing. It is conceivable to add a function of forming an image on the sensor by automatically controlling the position (hereinafter referred to as an autofocus function or AF).

However, there are problems with the mechanism that controls the projection lens, such as control failures caused by broken wires in the motor, obstacles that enter the range in which the lens moves, and control failures caused by frictional resistance between the lens and other parts. If an abnormality occurs, the above added functions will not be performed normally.

In such cases, if the operator notices the abnormality early,
Thereafter, there is no problem simply having the operator perform the above functions. However, if you are not aware of this, the following drawbacks may occur.

Image deterioration. That is, for example, if AF ends abnormally, the image input to the sensor will be defective.

Damage to equipment. Since the timing of countermeasures is delayed, it is easy to damage the part where the abnormality occurred or the parts related to it. This also increases the burden on services.

[Means to solve the problem]

The present invention has been made in view of the above points, and includes an imaging means for forming an image of transmitted light from a light-transmitting original on a predetermined surface, a moving means for moving the imaging position of the imaging means, and a moving means for moving the imaging position of the imaging means. a reading means for reading a document image using transmitted light focused on a surface of the image forming apparatus; a determining means for determining an abnormality regarding movement of the imaging position of the imaging means by the moving means; and displaying a determination result of the determining means. The present invention provides an image reading apparatus having a display means, and a detection means for detecting an image forming position of the image forming means, and the determining means includes a display means. The present invention provides an image reading device that determines an abnormality based on the output of the image reading device.

〔Example〕

The present invention will be explained below using Examples.

FIG. 1 is an external view of a film reading device.

701 is a reading device main body (scanner); 702 is a projector unit with a built-in lamp, condensing lens, etc.; 703 is a film holder for setting the film;
05 is a belt that transmits the rotation of the stepping motor 1014 to the projection lens 1018, 704 is a pulley directly connected to the stepping motor 1014, 706 is an original glass, 707 is a reflection mirror that reflects the light image from the projector unit 701, and 708 is a film. This is a Fresnel lens for forming an image on a reading section (a COD image sensor that photoelectrically converts an optical image) inside the scanner. 1020
is the operation section.

FIG. 2 is a block diagram of signal processing inside the scanner. 1
001 is B (blue) CCD, 1002 is G (green) COD, 1003 is R (red) CCD, 100
4 to 1006 are input color COD signal amplifiers, 100
7-1009 are analog/digital converters, 1010-
1012 is a buffer memory for transferring the A/D converted color digital signal to the microprocessor 1015, and stores 1947 worth of image data in the main scanning direction. Reference numeral 1013 is a color signal processing circuit that performs masking calculations, gamma conversion, etc., and converts input color signals into signals to be output to a printer. A stepping motor 1014 drives the projection lens 1018 to control the focus. 1015 is a microprocessor that performs (calculation of sampling parameter S for automatic focus control, control of lamp look-ahead power source 1016, drive of stepping motor 1014, etc.). 1016 is a power source that controls the amount of light from the lamp;
017 is a color printer, 1018 is a projection lens that controls the focal length, and 1019 is a limit switch that provides a reference point when rotating the projection lens. 1021 is a D/A converter, and microprocessor 1015
and controls the output/voltage of the lamp power supply 1016. Reference numeral 1020 denotes an operation unit, which includes a touch panel display 1101 and a start switch 11 shown in FIG.
Consists of 02.

1015-a is an RA possessed by the microprocessor 1015.
M and has battery backup.

This RAM I O 15-a has an area for storing temporary focus position data of the projection lens 1018, as shown in FIG. 4 401.

Next, the processing procedure regarding manual focus will be explained based on FIGS. 5 and 6.

First, the operator places a white paper under the Fresnel lens 708. Then, when the message shown in Figure 3 for selecting the focus adjustment method is being output on the touch panel display 1101, if the part labeled "Manual" is pressed, the control shown in the flowchart of Figure 5 starts. do.

That is, first, the projection lens 1018 is returned to the reference position (SP501). The details of this control procedure are as shown in the flowchart of FIG. 6. First, the stepping motor 1014 is driven in the backward direction every pulse, and the projection lens
018 is moved backward (SP601, 602), and then the stepping motor 1014 is driven in the forward direction every l pulse until the limit switch 1019 is turned OFF (SP603, 604).

However, even if the stepping motor 1014 is driven with a predetermined pulse and the projection lens 1018 is moved backward by the span of the maximum drive range, the limit switch 1019 may not turn on (SP605), or after moving the projection lens 1018 backward from the rear limit position. , even if the limit switch 1019 is advanced by the span that should turn OFF, the limit switch 1
019 is not turned off (SP606), a control error message prompting the user to check the projection lens 1018 as shown in FIG. 8 is displayed on the touch panel display 1101 (SP607).
, the movement control of the projection lens 1018 (driving of the stepping motor 1014) is stopped.

Note that (when the return to the reference position is successfully completed, the projection lens 1018 is advanced by the distance shown in the contents of the temporary focus position RAM in FIG. 4 (SP502).

Next, the hold on the stepping motor 1014 that drives the projection lens is released so that the operator can manually align the projection lens 1018 (SP503).

Then, turn on the lamp for 10 seconds (SP504.50
5゜506).

At this time, the operator moves the projection lens 1018 to focus while looking at the image projected on the white paper below the Fresnel lens 708.

FIG. 7 is a flowchart showing the processing performed by the microprocessor 1015 after the reading operation in the main body of the film reading apparatus is completed. First, a return to the standard is performed according to the procedure shown in FIG. 6 (SP701).

Next, the number of backward pulses required to return to the reference position is stored as temporary focus position data in the RAM shown in FIG. 4 (SP702).

In this way, the projection lens 1018 is connected to the stepping motor 1.
When the projection lens 1018 cannot be moved to a predetermined position, an error message is displayed and the lens movement control is stopped. Lens movement can be prevented.

[Other Examples]

In this embodiment, an abnormality related to the movement of the projection lens 1018 is detected based on the input image signal.

This embodiment will be described below with reference to FIGS. 9, 10, 11, and 12.

FIG. 9 is a sectional view of the film reading device.

901 is the main body of the reading device, 902 is a projector unit with a built-in lamp, condensing lens, etc., 903 is a carrier for setting the film, 904 is a belt that transmits the rotation of the stepping motor 1014 to the projection lens 1018, 905 is a document glass, 906 is a reflecting mirror, 9
07 is a Fresnel lens for forming a film image on a reading section inside the scanner.

A film image projected from the projector unit 902 is reflected by a reflection mirror 906, and a Fresnel lens 907
The light is focused on a mirror 908. Images reflected by mirrors 908 to 910 are sent to a CCD sensor 912 by an imaging lens 911.
is imaged. The CCD 912 is a 3-line parallel color sensor shown in FIG. A scanner motor 913 drives mirrors 908 and 910 to move the document reading position in the sub-scanning direction.

Next, the AF procedure in this embodiment will be explained based on the flowchart in FIG. First, the reflection mirror 908 is moved to the Fresnel lens 9 by the stepping motor 913.
control to position it in the center of 07 (spHol
). Next, the stepping motor 1014 moves the projection lens 1018 to the rear limit position where the limit switch 1019 is turned ON (sPH02).Next, the lamp is turned on and a film is set in the carrier and irradiated (sPH03).

In 5P1104, sampling data (AF data=S value) for automatic focus control is calculated. AF data is a parameter that reflects the sharpness of the target image, and in this example, the sum of squares S of the signal differences of adjacent pixels is S=Σ(X (i) −
G (green) signal X by the formula X (i-1)p
Calculated for (n) (n=o...N). In this embodiment, the input color sensor 912 is a 3-line parallel sensor as shown in FIG. 10, and the image is focused on a CCD 912 by a lens 911 shown in FIG. The camera is controlled by focusing on the middle sensor (in this embodiment, the G signal) among the two sensors.

Therefore, the G signal has the highest spatial resolution and is most suitable as a parameter that reflects the sharpness of the target image. The number of pixels in the main scanning direction on the sensor corresponding to the Fresnel projection plane is approximately 3000 pixels, and the central 1000 pixels in the main scanning direction of the Fresnel projection plane are targeted for calculation.

This AF data sampling is performed using the stepping motor 10.
14 every time the projection lens is advanced by one pulse,
Repeat until the front limit is located at a predetermined distance from the rear limit (SP1104-1106). As a result, as shown in FIG. 12, the S value corresponding to each position is determined.

Thereafter, the lamp is turned off (SP1107). Next, a (=
(SmaxSmin) / (Smax+
S min ) ) is calculated and if it is 1% or more, (splloB
), control the projection lens 1018 to the position where the S value takes the maximum value (Pk in Figure 12) (5P1109), and if it is less than 1%, output the error message in Figure 8 on the display as in the previous embodiment. (SPIIIO).

In this way, when the S value, which should normally produce a predetermined difference in value between the in-focus position and the out-of-focus position, is a roughly constant value, it is assumed that the lens 1018 is not moving well. It makes a judgment and displays an error.

Note that the rotary encoder is connected to a stepping motor 1014.
is connected to the stepping motor 1014, and detects step-out of the stepping motor by comparing the pulses input to the stepping motor 1014 and the pulses output from the rotary encoder.

〔Effect of the invention〕

As described above, by notifying the operator that an abnormality in the automatic control of the projection lens has been detected, it is possible to prevent image deterioration or damage to the apparatus due to the abnormality. Furthermore, by displaying the countermeasure method while also notifying the abnormality, the operator can quickly deal with the abnormality.

[Brief explanation of drawings]

Figure 1 is an external view of the reading device, Figure 2 is a signal processing block diagram, Figure 3 is an external view of the operation section, Figure 4 is a diagram showing the contents of the RAM, Figures 5, 6, and 7 and 11 are flowcharts of processing performed by the microprocessor, FIG. 8 is a diagram showing a display example, FIG. 9 is another configuration diagram of the film reading device, FIG. 10 is a configuration diagram of the COD, and FIG. The figure shows an example of the S value. 702 is a projector unit, 1O18 is a projection lens, 707 is a reflection mirror, and 1014 is a stepping motor. Pe

Claims (3)

[Claims] (1) An imaging means for forming an image of transmitted light from a light-transmissive original on a predetermined surface; a moving means for moving the imaging position of the imaging means; An image characterized by having a reading means for reading an image, a determining means for determining an abnormality regarding movement of the imaging position of the imaging means by the moving means, and a display means for displaying a determination result of the determining means. reading device. (2) An image reading device according to claim 1, further comprising a detection means for detecting an image forming position of said image forming means. (3) The image reading device according to claim 1, wherein the determining means determines the abnormality based on the output of the reading means.