JPH02110529A - Image pickup device - Google Patents

Abstract

PURPOSE:To prevent distortion from being generated in an image-pickup picture and to prevent the ununiformity of illuminance from being generated by forming the photosensitive part of an image sensor to be similar to the projection shape of a picture and obtaining an area corresponding to the projection shape of the picture for respective pixels. CONSTITUTION:An image pickup lens 24 and an image sensor 25 are arranged in a position, which is deviated from a printing optical path 15, so that no trouble can be caused on a photographic print. This image sensor 25 is arranged in a condition to be inclined to a negative film 16 only by an angle theta. In such a case, a photosensitive part 25a of the image sensor 25 is formed so as to correspond to the projection shape of the picture. Thus, the distortion of an image due to the oblique image-pickup of the picture can be canceled. Since the area of a pixel PE is changed corresponding to the distortion of the image, the ununiformity of the illuminance can be eliminated in the photosensitive part 25a.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an imaging device used in a photographic printer, a negative verification machine, and the like.

[Conventional technology]

Photographic printers and negative verification machines incorporate an imaging device in order to display a negative image recorded on a negative film on a monitor or to perform density measurement necessary for exposure control. This imaging device uses a MOS type or CCD type image sensor.

In a conventional photographic printer, a mirror inclined at 45 degrees is placed in and out of the printing optical path, and the light reflected laterally by this mirror is incident on an imaging device.

[Problem to be solved by the invention] When capturing a negative image using a mirror, since the negative film and the image sensor are parallel, it is necessary to form an image without distortion on the photosensitive part of the image sensor. Can be done. However, since a mechanism for taking in and out the mirror is required, this method is disadvantageous in terms of cost, space, and processing speed.

The above problem can be solved by arranging the image sensor diagonally so as not to interfere with photo printing, but in this case the image formed on the image sensor will be distorted into, for example, a trapezoid. It becomes an oval shape.

An object of the present invention is to provide an imaging device that prevents distortion from occurring in a captured image when the image is captured from an oblique direction.

[Means to solve the problem]

In order to achieve the above object, the present invention arranges an image sensor so as to be tilted with respect to the plane of the image and to capture an image from an oblique direction, and a photosensitive part of the image sensor. It is characterized by having a shape corresponding to the projected shape of the image.

It is preferable to set the area of each pixel so that when an image with uniform brightness is captured, the output of each pixel of the photosensitive section has the same value.

[Effect]

Since the photosensitive portion of the image sensor is made similar to the projected shape of the image, distortion of the image is canceled. Further, since each pixel has an area corresponding to the projected shape of the image, uneven illuminance does not occur.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 3 shows a photo printer. A cyan filter 12. is provided between the light source 10 and the mirror box 11. Magenta filter 13. A yellow filter 14 is arranged, and as is well known, it is red.

The amount of insertion into the printing optical path 16 is adjusted depending on the exposure amount of green and blue. The printing light that has passed through a portion of these color filters 12 to 14 is sufficiently diffused within the L-shaped mirror box 11 and illuminates the negative film 16 placed below. When printing a photograph, the shutter 18 is opened for a certain period of time, and during that time the negative image recorded on the negative film 16 is printed and exposed onto the color paper 20 via the printing lens 19.

The imaging lens 24 and the image sensor 25 are located away from the printing optical path 15 so as not to interfere with photographic printing.
and are arranged. This image sensor 25 is arranged at an angle θ with respect to the negative film 16. The video signal output from the image sensor 25 is sent to the monitor 27 via the video circuit 26, and a negative image is displayed on the monitor display surface.

FIG. 4 shows the relationship between the negative film and the image sensor. The image sensor 25 is a negative film 1
6, a distorted image is formed on the photosensitive portion 25a.

In this embodiment, a rectangular negative image 30 is distorted to become a trapezoidal image 31, and this trapezoidal image 31 is captured and displayed on the monitor 2.
7 is displayed. Such image distortion is caused by the photosensitive section 25.
This can be solved by making the shape of a congruent with the projected shape of the image.

In the embodiment shown in FIG. 1, the photosensitive portion 25a is shaped like a trapezoid, and each pixel is formed to match the trapezoid. In other words, the photosensitive area 25a is divided into a plurality of rows, and horizontal lines at a constant pitch are drawn by drawing rays at the same angle from the intersection point, centered on the point where the two inclined sides of the trapezoid intersect. is divided into a plurality of rows, thereby forming a large number of pixels PE.

FIG. 2 shows an example in which the area of each pixel PE is changed according to the distortion of the image so that uneven illuminance does not occur. That is, in the photosensitive portion 33a of the image sensor 33, the horizontal lines are wide in the portion where the distortion is large. Thereby, when a negative image with uniform brightness is captured, the output value of each pixel PE can be made the same.

In the above embodiment, an imaging device for a monitor has been described, but the present invention can also be applied to an imaging device for measuring density used in calculation of exposure amount.

〔Effect of the invention〕

According to the present invention having the above configuration, since the photosensitive portion of the image sensor is formed to correspond to the projected shape of the image, it is possible to cancel the influence of image distortion caused by capturing the image obliquely. can. Furthermore, since the area of the pixel is changed according to the distortion of the image, it is possible to eliminate uneven illuminance on the photosensitive area.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an embodiment of the image sensor of the present invention. FIG. 2 is a plan view showing another embodiment of an image sensor in which uneven illuminance does not occur. FIG. 3 is a schematic diagram showing a photographic printer incorporating the imaging device of the present invention. FIG. 4 is an explanatory diagram showing the projected shape of a negative image. l 6 ・ 24 ・ 25 ・ 5a 33 ・ 3a PE ・ Negative film imaging lens image sensor Photosensitive part image sensor Photosensitive part pixel 1 Fig. 2

Claims (2)

[Claims] (1) The image sensor is arranged so as to be tilted to the plane of the image and capture the image from an oblique direction, and the photosensitive part of the image sensor is shaped to correspond to the projected shape of the image. imaging device. (2) The imaging device according to claim 1, wherein the area of each pixel of the photosensitive section is set so that when an image with uniform brightness is captured, the output of each pixel of the photosensitive section has the same value. .