The present invention relates to (1) a photograph printing device, for use in, for example, a photograph processing device or photograph printer, which, by projecting light onto a photosensitive material through an information holding medium (such as a film negative recording an original image, or a liquid crystal display element, PLZT exposure head, DMD (digital micromirror device), etc. driven by image signals corresponding to the original image), prints an image corresponding to the original image onto the photosensitive material; (2) an electronic image input device including the foregoing photograph printing device and an image pickup element such as a CCD (charge coupled device); (3) a film scanner, for use in, for example, a digital printing system, which, by scanning light obtained through film recording an original image, registers the original image; (4) a scratch recognition method for recognizing a scratch formed on the foregoing film; (5) a memory medium recording a program for scratch recognition; and (6) an image restoration method for restoring a scratch area of an image obtained by scanning.
In the past, various photograph printing devices have been proposed in which, for example, a film negative recording an original image is placed in front of a photosensitive material, and an image corresponding to the original image is printed onto the photosensitive material by projecting light onto the photosensitive material through the film negative.
In this type of photograph printing device, a halogen lamp is usually used as the light source for projecting light onto the photosensitive material. Further, by interposing in the light path three different cutoff filters with different respective spectral characteristics, corresponding to red, green, and blue, the light from the halogen lamp is adjusted to light suited to photograph printing.
However, photograph printing devices which use a halogen lamp as the light source have the following problems.
(1) Since halogen lamps produce large amounts of heat, which is unnecessary in photographic printing, forced cooling means such as a cooling fan are necessary. Here, use of a cooling fan is a hindrance to good printing, because surrounding dust is sucked into the optical system.
(2) A stable direct-current power source for stabilizing the spectral characteristics of the halogen lamp, a light-adjusting filter, cutoff filters for cutting out infrared and ultraviolet light, etc. are also necessary, thus increasing the size of the device.
(3) Since a desired light quantity necessary for printing cannot be obtained until a certain time has passed after turning on the halogen lamp, the halogen lamp must be left turned on even when not printing. This increases the power consumption of the halogen lamp. Further, to prevent light from the halogen lamp from reaching the photographic paper (photosensitive material) when not performing printing, a shutter mechanism between the photographic paper and the halogen lamp is necessary, thus increasing the number of structural parts.
(4) Given that light quantity differs greatly between the light axis and surrounding areas, a scattering device is often provided to scatter the light from the halogen lamp to create a planar light source necessary in printing. This increases loss of light quantity.
(5) If the halogen lamp is always left turned on, when printing a large number of photographs, heat from the halogen lamp has an adverse effect on the film negatives.
The problems in (1) through (5) above also arise with film scanners, in which a film negative recording an original image is placed in front of a scanning section, and the scanning section registers the original image by scanning light projected through the film negative. Such a film scanner is connected to a digital printer through, for example, a computer such as a personal computer, and images read by the film scanner are outputted by the digital printer.
A photograph printer and a film scanner disclosed in Japanese Unexamined Patent Publication No. 8-22081/1996 (Tokukaihei 8-22081) use as light source a plurality of light emitting diodes (hereinafter referred to simply as xe2x80x9cLEDsxe2x80x9d) having different respective spectral characteristics, thus avoiding the foregoing problems caused by the halogen lamp. The following will explain in outline the structure of an exposure projection section of the photograph printer disclosed in the foregoing publication.
As shown in FIG. 33, the foregoing conventional photograph printer includes an LED light source 101, a scattering plate 102, and a lens 103.
The LED light source 101 is made up of a plurality of LEDs 101a, each of which projects red, green, or blue light, arranged in matrix form. Here, each of the LEDs 101a is provided so that light emitted thereby has directivity in a direction parallel to a light axis L, as shown in FIG. 33. Further, each LED 101a is independently ON/OFF controlled by a light source driving section (not shown), by means of which the duration and/or brightness of illumination of each LED 101a is controlled.
The scattering plate 102 is provided on the side of the LED light source 101 from which light exits, and scatters the light projected thereby. The lens 103 focuses an optical image, incident thereon, onto color photographic paper 105 (photosensitive material).
In the foregoing structure, when the LEDs 101a of the LED light source 101 are lit, light projected from each LED 101a is scattered by the scattering plate 102, passes through a film negative 104 set in a printing position and the lens 103, and reaches the color photographic paper 105. In this way, an image corresponding to the original image recorded on the film negative 104 is focused on and printed onto the color photographic paper 105.
The film scanner disclosed in the foregoing publication is structured as the foregoing photograph printer, except that the color photographic paper 105 is replaced by an image area sensor 106. Accordingly, in the foregoing film scanner, when the LEDs 101a of the LED light source 101 are lit, light projected from each LED 101a is scattered by the scattering plate 102, passes through the film negative 104 and the lens 103, and reaches the image area sensor 106. In this way, an image corresponding to the original image recorded on the film negative 104 is focused on a photoreceptive surface of the image area sensor 106. Then, if the film scanner is connected to a digital printer through, for example, a computer such as a personal computer, a sheet recording an image corresponding to the original image is discharged from the digital printer.
However, in the photograph printer disclosed in the foregoing publication, since each LED 101a is provided so that light emitted thereby has directivity in a direction parallel to the light axis, due to the influence of, for example, aberration arising from the design of the optical system, the light quantity of light projected onto peripheral areas of the color photographic paper 105 is decreased, resulting in unevenness in density and color between central and peripheral areas.
Some methods of avoiding this difficulty are the following. One is a method in which the scattering plate 102 is thicker in the central portion and thinner toward the periphery, thereby further scattering light so as to reduce the light quantity in the central area of the color photographic paper 105 and increase the light quantity in the peripheral areas of the color photographic paper 105. Another method is one in which the scattering plate 102 is made of frosted glass of a coarseness which can barely be seen through with the naked eye, thereby scattering the light as in the method above.
However, with methods such as these, which scatter light, loss of light quantity is increased, and thus it is necessary, for example, to increase the exposure time of each LED 101a, increase the brightness of illumination of each LED 101a, etc. This results in the further problem that adjustment of uneven density requires time and effort.
Further, in FIG. 34, which shows the intensity distribution of light from each LED 101a, it can be seen that intensity is high near the center of each light spot, but decreases with distance from the center.
In the photograph printer disclosed in the foregoing publication, since each LED 101a emits light having directivity parallel to the light axis, light spots of the LEDs 101a are dispersed across the color photographic paper 105 in positions corresponding to the LEDs 101a, as shown in FIG. 34, giving rise to marked color unevenness. In other words, this color unevenness is due to the fact that the light spots projected onto the color photographic paper 105 appear with a one-to-one correspondence with the LEDs 101a. 
One possible method of reducing this kind of color unevenness is to project scattered light onto the film negative 104 using LEDs 101a having a wide directivity. However, since the principle of this method remains scattering of light, to reduce the resulting loss of light quantity, it is again necessary to increase the exposure time or brightness of each LED 101a. Here again, this results in the problem that adjustment of color unevenness requires time and effort.
On the other hand, another possible solution is to use LEDs 101a of narrow directivity, but to greatly increase their number, thereby increasing the density of the light spots to eliminate color unevenness. However, it is extremely difficult to provide LEDs 101a numerous enough to reduce color unevenness, and even if enough LEDs 101a could be provided, fine control of such a large number of LEDs 101a would be nearly impossible in practice.
Further, in the film scanner disclosed in the foregoing publication, if the film negative 104 includes a scratch area disturbing the light path from the LED light source 101 to the image area sensor 106, a scratch image (such as a white area) corresponding to the scratch area appears in the scanning image. This is because light incident on the scratch area is refracted thereby, and diverges from the light path leading to the image area sensor 106, resulting in insufficient light quantity at the scratch image. Further, this phenomenon of insufficient light quantity resulting from irregular refraction, etc. also occurs when dust, foreign objects, etc. are attached to the film negative 104.
However, in the foregoing conventional film scanner using the LED light source 101, a scratch area on the film negative 104 cannot be recognized. In other words, when there is a scratch area on the film negative 104, a white area appears in the scanning image obtained by the image area sensor 106, but even if this white area is recognizable as a scratch image by human eyes, the computer is unable to distinguish whether the white area is a scratch image or a legitimate image corresponding to the original image recorded on the film negative 104.
As a result, in the foregoing conventional film scanner, when there is a scratch area on the film negative 104, it is not possible to restore only the corresponding scratch image, and thus it is impossible to obtain a good print free of scratch images.
It is an object of the present invention to provide a photograph printing device capable of simple adjustment of unevenness in density and color on photographic paper; an electronic image input device including such a photograph printing device and an image pickup element; a film scanner which, when film recording an original image includes a scratch area disturbing the light path to a scanning section, is able to distinguish the scratch area from non-scratch areas, and to restore an image corresponding to the scratch area; a scratch recognition method; a memory medium recording a scratch recognition program; and an image restoration method.
In order to attain the foregoing object, a photograph printing device according to the present invention, by projecting light onto a photosensitive material through an information holding medium which holds original image information, prints onto the photosensitive material an image corresponding to the original image information, and is provided with a light source for projecting light onto the information holding medium; in which the light source includes a plurality of light emitting means having different respective spectral characteristics, and each of the light emitting means is provided so as to incline with respect to a light axis, so that light emitted thereby has directivity toward the light axis.
With the foregoing structure, since light projected from each of the light emitting means has directivity, even if aberration, etc. occurs in the optical system, the light quantity of light projected through the information holding medium onto the peripheral areas of the photosensitive material is increased in comparison with the conventional art, in which light emitting means were provided so that light emitted thereby has directivity in a direction parallel to the light axis. In this way, unevenness in density and color on the photosensitive material can be easily distinguished, without scattering the light from the light emitting means more than necessary, as was done conventionally. Accordingly, there is no need for control which attempts to obtain sufficient scattered light by increasing the exposure time or brightness of each light emitting means.
Further, since each light emitting means inclines with respect to the light axis, light spots with a one-to-one relationship to the light emitting means do not appear on the photosensitive material. As a result, color unevenness can be suppressed to some extent, and thus, as above, there is no need to scatter the light from the light emitting means more than necessary, nor to provide a large number of light emitting means.
For these reasons, with the foregoing structure, control of each of the light emitting means is simplified, thus facilitating adjustment of unevenness in density and color.
An electronic image input device according to the present invention includes the foregoing photograph printing device, and image pickup means, which pick up light from the light emitting means obtained through the information holding medium.
With the foregoing structure, by replacing the photosensitive material of the foregoing photograph printing device with the image pickup means, adjustment of density and color unevenness, for example, can be performed directly, on the basis of output from the image pickup means, prior to printing. In other words, if the image pickup means are, for example, a CCD, since the CCD outputs electrical signals corresponding to the light quantity received by each pixel thereof, the detected signals from the CCD can be used to register density distribution of an optical image focused on a photoreceptive surface of the CCD. Accordingly, it is not necessary to perform test printing to detect unevenness in density and color, and, as a result, adjustment of density unevenness and color unevenness can be performed quickly.
A film scanner according to the present invention includes a first light source, which projects light onto film recording an original image; scanning means, which register the original image by scanning light transmitted through the film; and light compensating means, which compensate insufficient light quantity due to disturbance of the light path from the first light source to the scanning means by an irregularity in the surface of the film (for example, surface unevenness such as a scratch), which causes an image of the irregularity to be formed in the scanning means, using the disturbance of the light path caused by the irregularity.
In the foregoing structure, when there is unevenness in the film surface, such as a scratch or dust, light from the first light source incident on the film surface is subject to refraction, etc. due to the surface unevenness, and is thus unable to follow the normal light path to reach the scanning means. In other words, the scratch, dust, etc. acts as an irregularity disturbing the light path from the first light source to the scanning means. As a result, in the scanning means, the image at the position of the irregularity, due to insufficient light quantity, is not colored, and appears as, for example, a white area.
Here, by providing light compensating means which, for example, produce light which differs from the light produced by the first light source and which is projected onto the film surface from random directions, insufficient light quantity due to the irregularity can be compensated by taking advantage of the disturbance of the light path by the irregularity. In other words, by intentionally using the refraction, etc. of the irregularity to send light to the position of the image appearing as a white area due to the refraction, etc. of the irregularity, the image at the position of the irregularity can be colored. In this way, the white area at the position of the irregularity can be eliminated.
The light compensating means may be a light source which itself emits light, or they may be means which, by reflecting, refracting, etc., light from the first light source, create light projected onto the film surface from random directions.
A scratch recognition method according to the present invention includes the steps of projecting light onto film recording an original image; and recognizing the existence of a scratch area formed on the film by scanning light obtained through the scratch area.
With the foregoing method, by scanning, among the light projected onto the film, the light obtained through the scratch area, it is possible to recognize the existence of a scratch area on the film. In other words, a scratch image corresponding to a scratch area normally appears as a white area, and, by scanning the foregoing light, it can easily be distinguished whether such a white area is a scratch image or a legitimate part of the image corresponding to the original image recorded on the film.
Accordingly, if the existence of a scratch area can be recognized in this manner, it is then possible to perform processing to increase image density at the scratch image alone by, for example, adjusting emitted light quantity. As a result, scratch images can be restored with certainty.
A memory medium recording a scratch recognition program according to the present invention records a program which causes a computer to recognize the existence of a scratch area, formed on film recording an original image, by projecting light onto the film and scanning light obtained through the scratch area.
With the foregoing structure, since the memory medium records a program for projecting light onto the film recording the original image, and scanning, among the light projected onto the film, the light obtained through the scratch area, the computer automatically recognizes the existence of a scratch area on the film. Accordingly, in comparison with a case in which the operator checks scanning light on a monitor, for example, scratch recognition can be performed more quickly, and with less effort on the part of the operator.
An image restoration method according to the present invention includes the steps of (a) projecting light onto film recording an original image, and scanning light obtained through a scratch area formed on the film; (b) after step (a), projecting onto the film light differing from the light projected in step (a), and scanning light passing through areas of the film other than the scratch area; and (c) bringing density of an image obtained in step (a) into conformity with density of an image obtained in step (b).
With the foregoing method, first, by scanning light obtained through the scratch area formed on the film, the existence of the scratch area on the film is recognized, and the image recorded in the scratch area (hereinafter referred to as the xe2x80x9cfirst imagexe2x80x9d) is obtained. However, density of the first image corresponds to the extent (depth, for instance) of the scratch area; the deeper the scratch, the lower the density.
Next, by scanning light passing through areas of the film other than the scratch area, the image recorded in the areas of the film other than the scratch area (hereinafter the xe2x80x9csecond imagexe2x80x9d) is obtained, and then, finally, density of the first image is adjusted so as to substantially conform with density of the second image.
Accordingly, even when a scratch area is formed on the film, by recognizing the scratch area, the scratch image (white area, for example) alone can be restored. As a result, it is possible to obtain good prints free of scratch images.