JP2001142163A - Infrared cut filter for film image reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent overheating of a photographic film or optical parts even with a film image reader which detects an IR image. SOLUTION: The IR cut filter for the film image reader arranged in mid-way of an optical path for film image reading of the film image reader 4 for reading the image of the photographic film 1 by irradiating the photographic film 1 with the light emitted from a light source 31a is so constituted as to permit the transmission of the IR rays of a set wavelength range in order to allow the image detection by an IR image detecting means 34 and to cut the IR rays exclusive of the set wavelength range.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film image reading apparatus for reading an image on a photographic film by irradiating light emitted from a light source onto the photographic film. The present invention relates to an infrared cut filter for a device.

[0002]

2. Description of the Related Art Such an infrared cut filter for a film image reading device generally has a wavelength characteristic as shown in FIG. 4, and in a film image reading device, infrared light is removed from light emitted from a light source. It is used to prevent unnecessary temperature rise of photographic film or optical parts. Therefore, conventionally, when an infrared image detecting means is provided in a film image reading apparatus and infrared light is to be detected, it is necessary to remove such an infrared cut filter and detect the infrared light. In addition, as a case where infrared rays are to be detected as described above, there are cases where a flaw or dust on a photographic film is to be detected as an image.

[0003]

However, if the infrared cut filter is removed as in the above-mentioned prior art, there is a risk that the photographic film or optical parts will be overheated. The present invention has been made in view of the above circumstances, and an object of the present invention is to prevent overheating of a photographic film or an optical component even in a film image reading apparatus that attempts to detect an infrared image.

[0004]

According to the first aspect of the present invention, when an infrared cut filter for a film image reading device is disposed in the middle of an optical path for reading a film image of the film image reading device, the film image reading device is provided. The light emitted from the light source of the apparatus passes through an infrared cut filter for a film image reading apparatus to allow transmission of infrared rays in a set wavelength range, but cuts out infrared rays outside the set wavelength range. This makes it possible to detect an image by the infrared image detecting means, but it is possible to cut off infrared rays of wavelengths not required by the infrared image detecting means, and thus, a film image reading apparatus for detecting an infrared image However, overheating of the photographic film or the optical component can be prevented.
In addition, as described above, for cutting the infrared light of wavelengths other than the set wavelength range, it is not necessary to block the transmission of infrared light for the entire range other than the set wavelength range, and the temperature rise of optical components and the like is within the allowable range. The wavelength range to be cut may be set as appropriate so as to fall within the range.

According to the second aspect of the present invention, when the infrared cut filter for the film image reading device is disposed in the middle of the optical path for reading the film image, the intensity of the light incident on the infrared image detecting means is reduced. The signal intensity is equal to or less than the light intensity at which the signal is saturated and equal to or greater than half the signal intensity of the saturated state. Accordingly, the infrared image detecting means is ensured to have a sufficient infrared intensity for image detection, and the intensity is not excessive, so that the infrared image can be accurately detected.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an infrared cut filter for a film image reading apparatus according to the present invention will be described below with reference to the drawings. The image printing apparatus IP using the infrared cut filter for the film image reading apparatus of the present invention adopts a digital exposure type, and as shown in FIG. 1, a photograph developed by a film developing machine not shown here. A film scanner 3 as a film image reading device for reading a frame image of a film (hereinafter simply referred to as a film) 1 as digital image data; a controller 7 for processing the obtained digital image data to create print data; A digital printing unit 5 for exposing an image corresponding to a frame image to the photographic paper 2 based on the data, and a development processing unit 6 for developing the exposed photographic paper 2 are provided. The photographic paper 2 developed by the development processing section 6 is discharged as a finished print through a drying process.

The film scanner 3 includes, as main components, an illumination optical system 31, an imaging optical system 32, a photoelectric conversion unit 33 for visible light using a CCD sensor, and infrared light as infrared image detecting means using a CCD sensor. The optical photoelectric conversion unit 34 is provided. The illumination optical system 31 includes a halogen lamp 31a as a light source, a reflecting mirror 31b that reflects the light of the halogen lamp 31a into substantially parallel light, an infrared cut filter 31c, and a light of a desired color. A dimming filter 31d for adjusting the balance and a mirror tunnel 31e for uniformizing the color distribution and intensity distribution of light are provided.

The film scanner 3 of the present embodiment is provided with the infrared light photoelectric conversion unit 34 as described above, and obtains, as will be described in detail later, the state of scratches and dust on the film 1 as image information. It is configured as follows. Therefore, it is necessary for the above optical system to allow the infrared light photoelectric conversion unit 34 to pass infrared light in a wavelength range to be detected. For this reason, as shown in FIG. 2, the infrared cut filter 31 c has, in principle, a sufficiently low transmittance in the infrared wavelength range of about 780 nm to about 1100 nm. About 820 nm to be detected
The transmittance is set slightly higher in the wavelength range of about 890 nm. That is, in order to enable image detection by the infrared light photoelectric conversion unit 34, transmission of infrared light in the above-mentioned set wavelength range is allowed, and infrared rays outside the set wavelength range are cut off. In addition, the infrared rays are not cut in the entire region on the longer wavelength side than 1100 nm, and the transmittance increases in a range where the temperature rise due to the infrared rays does not matter.

As shown in FIG. 3, the dimming filter 31d adjusts the color balance by giving a predetermined wavelength dependency to the transmittance in the visible light region on the shorter wavelength side than about 780 nm. In the range of infrared rays of 790 nm to about 1000 nm, the transmittance is sufficiently low in principle, but about 820 nm to about 89 to be detected by the infrared light photoelectric conversion unit 34.
The transmittance is set slightly higher in the wavelength range of 0 nm. In order to give the infrared cut filter 31c and the dimming filter 31d the above-mentioned wavelength specification, these filters are formed by a so-called interference filter composed of a multilayer film. It may be realized by a glass filter, or may be realized by overlapping a plurality of glass filters having different wavelength characteristics for cost reduction.

An image pickup optical system 32 includes a zoom lens unit 32a and a mirror 32b for bending a traveling direction of a light beam.
And an infrared cut filter 32c. The mirror 32b has a reflection surface equivalent to that of a so-called cold mirror, and visible light is reflected by the reflection surface of the mirror 32b to bend the optical path by 90 degrees, but most of the infrared light passes through the mirror 32b. And go straight. The infrared cut filter 32c is for reliably removing a small amount of infrared light reflected by the mirror 32b, and is different from the infrared cut filter 31c of the illumination optical system 31 described above, and is different from the conventional infrared cut filter shown in FIG. It has the same characteristics as a filter.

The transmittance of the infrared cut filter 31c and the light control filter 31d in the infrared wavelength range of about 820 nm to about 890 nm to be detected by the infrared photoelectric conversion unit 34, and the transmittance of the mirror 32b. The transmittance in the wavelength range is such that the incident light intensity of the infrared light that passes through the mirror 32b and enters the infrared light photoelectric conversion unit 34 is equal to or less than the light intensity at which the output signal of the infrared light is saturated, and is 1/1 of the saturation state. The light intensity is set to be within the range of the light intensity that is equal to or higher than the signal intensity of No. 2.

The visible photoelectric conversion unit 33 includes an imaging optical system 32.
Of visible light of the light beam guided by the CCD, and is a visible light CCD line sensor unit 33a.
And a visible light signal processing circuit 33b that performs processing such as amplification and A / D conversion of the detection signal of the visible light CCD line sensor unit 33a and outputs the processed signal to the controller 7. The visible light CCD line sensor unit 33a includes a set of a large number (for example, 5000) of light receiving elements arranged in the main scanning direction, that is, the width direction of the film 1, and a transfer unit for transferring electric charges generated by the light receiving elements. It is provided corresponding to each color of red (R), green (G), and blue (B), and these are integrated on one chip.
Further, R, G, B color filters are formed on the light receiving surface of each light receiving element.

The infrared light photoelectric conversion unit 34 is provided with an infrared light CC.
D line sensor unit 34a and its infrared CCD
The detection signal of the line sensor unit 34a is amplified and A /
An infrared light signal processing circuit 34b that performs processing such as D conversion and outputs the result to the controller 7 is provided. The infrared light CCD line sensor unit 34a has the same configuration as the visible light CCD line sensor unit 33a, but the visible light CCD line sensor unit 33a
Although three CCD line sensors are provided for each of R, G, and B, only a CCD line sensor for infrared light is provided.

When the frame image of the film 1 is positioned at a predetermined scanning position, a reading process of the frame image is started. The projected light image of the frame image is sequentially divided into a plurality of slit images by the film transport mechanism 9 in the sub-scanning direction of the film 1 and is sequentially divided into the visible light CCD line sensor unit 33a and the infrared light CCD. The image data is read by the line sensor unit 34a, photoelectrically converted into image signals of R, G, and B color components and image signals of infrared light components, and sent to the controller 7 as raw digital image data. Such control of the illumination optical system 31, the imaging optical system 32, the visible light photoelectric conversion unit 33, and the infrared light photoelectric conversion unit 34 of the film scanner 3 is performed by the controller 7. The film scanner 3 has a function of reading print size information and the like magnetically recorded on the film by a magnetic reading head (not shown) in addition to reading the image data of the film described above.

In this embodiment, the digital print section 5 employs a PLZT shutter system. That is, a shutter array including a PLZT element is employed as the exposure head 5a. R, G, and R are provided to each shutter from the light source unit 5b via the optical fiber bundle 53.
Light of each color B is introduced. The shutter array extends over the photographic paper 2 arranged in two rows along the width direction of the photographic paper 2, that is, in the transverse direction of the transport direction, and when a voltage of a predetermined level is applied to each shutter, a light transmitting state ( (Open state), and when the application of the voltage is stopped, the light enters a light blocking state (closed state). Corresponding to the pixels of the image exposed by each shutter, opening and closing each shutter exposes one line of image data extending in the transport width direction by one pixel in the photographic paper transport direction at a time.

Although not shown, the light source unit 5b includes a light source lamp, a dimming filter for adjusting light emitted from the light source lamp to a desired color balance, a rotation filter, and the like. The rotary filter has optical filters of three colors, red (R), green (G), and blue (B), which are arranged side by side in the circumferential direction. , B selectively face the light source, and the light of the selected color is sent to the shutter through the optical fiber via the filter of that color.

Based on the image information of the image input from the film scanner 3, the controller 7 controls each pixel, that is, each shutter so that the image can be properly reproduced on the photographic paper 2. , B, the length of time during which the shutter opens is set as the exposure amount. As a method of the digital printing section, in addition to the PLZT shutter method, a liquid crystal shutter method, a fluorescent beam method,
The FOCRT method is known, and can be arbitrarily selected according to the exposure specification.

The transport system of the photographic paper 2 for transporting the photographic paper 2 to the digital print section 5 and further transporting the photographic paper 2 exposed by the digital print section 5 to the development processing section 6 is shown in FIG. As shown in FIG. 1, a photographic paper supply line 8A for transporting the photographic paper 2 in a single row, an exposure transport line 8B for transporting the photographic paper 2 in two rows, and a development transport line 8C are divided into photographic paper supply lines 8A. A sorting device 4 for sorting the photographic paper 2 sequentially sent from the photographic paper supply line 8A to each row of the exposure and conveyance line 8B is provided between the photographic paper supply line 8A and the exposure and conveyance line 8B.

As can be seen from FIG. 1, the photographic paper supply line 8A is selected from one of two photographic paper magazines 10 containing a long photographic paper 2 in a roll shape with the photosensitive surface on the outside. It includes a drawing roller group 8a for drawing out the printing paper 2 and a pre-sorting roller group 8b for transferring the printing paper 2 to the sorting device 4. A paper cutter 11 that cuts the photographic paper 2 pulled out from the photographic paper magazine 10 according to a print size corresponding to an area for exposing each image is provided on the downstream side of the conveyance of the drawer roller group 8a. A back print unit 12 is provided downstream of the paper cutter 11. The back print unit 12 prints a film ID, a frame number, correction information indicating image processing performed at the time of creating print data, and the like on the back surface (the surface opposite to the photosensitive surface) of the photographic paper 2. Usually, a dot-in-packed printer is used.

The pre-sorting roller group 8b is disposed so as to sandwich the back print unit 12, and is composed of a driving roller 81 contacting the non-photosensitive surface side of the photographic paper 2 and a pressure roller 82 contacting the photosensitive surface side. The pressing roller 82 is the driving roller 8
1. The printing paper 2 can be pressed and released between the driving roller 81 and the pressing roller 82 by being displaceable in the near and far directions.

The exposure transport line 8B is provided with a wide transport roller unit and corresponding to each row so that the photographic paper 2 cut corresponding to each frame can be transported simultaneously in two rows side by side. A guide member is provided. However, in the transport roller unit on the most upstream side of the transport, the drive roller 83 is a wide roller that covers two rows.
Are divided into a right-side pressing roller 84a and a left-side pressing roller 84b. That is, the pressure roller 84a for the right row and the pressure roller 8 for the left row
4b can be performed independently of each other, and the two cut photographic papers 2 are received and held in order by the rollers 84a and the pressure roller 84b, and simultaneously the two photographic papers 2 are exposed to the exposure head 5a. To the exposure position EP.

A first transport roller R1, a second transport roller R2 on the outlet side, and an electric motor for driving these rollers are provided on both sides in the transport direction of the exposure position EP of the exposure head 5a. The first transport roller R1 includes a first driving roller 85 that contacts the non-photosensitive surface of the printing paper 2 and the first driving roller 85.
And a second pressure roller 86 that is driven to move toward and away from the photographic paper 2, and the second transport roller R2 is a second drive roller 87 that contacts the non-photosensitive surface side of the photographic paper 2.
And a second pressure roller 88 which is driven to move toward and away from the second driving roller 87. Switching of the first and second transport rollers R1 and R2 between the pressure-bonded state and the released state is controlled by the controller 7,
While the photographic paper 2 is being conveyed via the exposure position EP,
The transport state of the photographic paper 2 is a state where it is transported and driven only by the first transport roller R1, a state where it is transported and driven by both the first transport roller R1 and the second transport roller R2, and a second transport roller R
The state is sequentially switched to three transport states in which the transport is driven by only 2.

On the downstream side of the second transport roller R2, the transport path is curved with a curved guide (not shown), and the first turn drive roller 91 and the first turn drive roller are provided along the path. A first-turn pressing roller 92 that can be displaced in the near and far directions with respect to 91, a second-turn driving roller 93, and a second-turn pressing roller 94 attached to face the second-turn driving roller 93 are arranged. . A curved guide (not shown) disposed between the first and second turn transport pressure rollers 91 and 93 has a guide portion on the non-photosensitive surface side which swings outward around a swing fulcrum provided on the downstream side of the transport. The printing paper 2 that is movable and passes through the curved guide can be inflated outward as needed. still,
First turn drive roller 91 and first turn pressure roller 92
Is performed after both of the printing papers 2 to be pressed and conveyed in two rows have completed passing through the exposure position EP and the exposure operation has been completed.

As shown schematically in FIG. 1, the sorting device 4 for sorting the photographic paper 2 sequentially sent from the carry-out area of the photographic paper supply line 8A to the carry-in area of each row of the exposure carrying line 8B has a The first and second chuckers 60A and 60 are driven to move in the vertical and horizontal directions.
B is provided. Although not shown, the first chucker unit 60A and the second chucker unit 60B can sandwich and convey the photographic paper 2, and the first chucker unit 60A receives the photographic paper 2 from the downstream end of the photographic paper supply line 8A. The photographic paper 2 is delivered to a pair of an intermediate drive roller 83 and a first intermediate pressure roller 84a, and the second chucker unit 60B transfers the photographic paper 2 received from the downstream end of the photographic paper supply line 8A to the intermediate drive roller 83. It is delivered to a pair with the second intermediate pressure roller 84b, and the first chucker 6
0A and the second chucker section 60B alternately carry up and down, and distribute the photographic paper 2 to each of two rows of carrying paths on the exposure carrying line 8B.

Next, a printing operation in the image printing apparatus IP having the above-described configuration will be schematically described. First, when the film 1 for producing a print is loaded into the film scanner 3, the image of each frame of the film 1 is read while being conveyed by the film conveying mechanism 9. The image of the film 1 is read by reading the original image information photographed on the film 1 by the visible light photoelectric conversion unit 33 and photographing the film 1 by the infrared light photoelectric conversion unit 34. The image information of scratches and dust on the film 1 is read instead of the original image information. The reason that such image information can be read by the infrared light photoelectric conversion unit 34 is that the infrared light incident on the film 1 is not affected by the photographed image itself recorded on the film 1, If the above-mentioned scratches and dusts are present, they are scattered by them and the amount of transmitted light is reduced, and the presence of the scratches and dusts can be obtained as image information.

The visible image detected by the visible light photoelectric conversion unit 33 and the infrared image detected by the infrared light photoelectric conversion unit 34 are input to the controller 7, respectively. The controller 7 sets the exposure amount for each pixel for each color of the image exposed by the exposure head 5a based on the density information for each color of the visible image input from the photoelectric conversion unit 33 for visible light. At this time, if there is a flaw or dust on the film 1, the detection density of the flaw or dust existing part in the image detected by the visible light photoelectric conversion unit 33 has changed from the original image density information. When the exposure amount is set, the quality of the obtained print is deteriorated due to the presence of scratches and dust. For this reason, the controller 7 specifies the position where the scratch or dust exists on the film 1 based on the detection information of the infrared light photoelectric conversion unit 34, and detects the scratch or dust in the detection image information of the visible light photoelectric conversion unit 33. The detected density information of the existing portion is corrected from the density information of the surrounding image by a complementing process or the like, and the exposure amount is set based on the corrected density information.

When the exposure amount is set for each pixel in this way, the exposure head 5a is exposed to the photographic paper 2 transported along the exposure transport line 8B and passing through the exposure position EP with the set exposure amount. To expose the image. The photographic paper 2 on which the exposure processing has been completed is conveyed to the development processing section 6, where the photographic paper 2 is subjected to development processing, and after drying, is discharged as a completed print.

[Other Embodiments] Other embodiments will be listed below. In the above embodiment, the film image reading device to which the infrared cut filter of the present invention is applied includes the visible light photoelectric conversion unit 33 and the infrared light photoelectric conversion unit 34, and converts visible light and infrared light. Although it is detected by a separate sensor, a CCD line sensor 34a for infrared light is further integrated with the visible light CCD line sensor unit 33a of the visible light photoelectric conversion unit 33, and the visible light is detected by a single sensor. The infrared cut filter of the present invention may be applied to a film image reading device that detects both infrared light and infrared light. In the above embodiment, the wavelength range of the infrared light to be detected by the infrared image detecting means is approximately 820 nm to
Although the wavelength range of about 890 nm is illustrated, this may be variously changed according to the detection characteristics of the infrared sensor used in the infrared image detecting means.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram of an image printing apparatus to which the present invention is applied.

FIG. 2 is a diagram showing a wavelength characteristic of the infrared cut filter according to the embodiment of the present invention;

FIG. 3 is a diagram showing wavelength characteristics of the light control filter according to the embodiment of the present invention;

FIG. 4 is a diagram showing wavelength characteristics of a conventional infrared cut filter.

[Explanation of symbols]

 Reference Signs List 1 photographic film 3 film image reader 31a light source 34 infrared image detecting means

 ────────────────────────────────────────────────── ─── Continued on the front page F term (reference) 2H048 AA19 AA29 CA18 2H106 AA13 AA48 AB04 AB72 BA22 BA29 2H110 AA18 AB08 CB03 CE04 5C062 AA05 AB00 AB03 AB17 AC48 BA07 5C072 AA01 BA13 BA20 DA09 RA01 VA03 XA10

Claims (2)

[Claims] 1. An infrared cut filter for a film image reading device, which is disposed in the middle of a film image reading optical path of a film image reading device that irradiates light emitted from a light source onto a photographic film and reads an image of the photographic film. An infrared cut for a film image reading apparatus, which is configured to allow transmission of infrared light in a set wavelength range and cut infrared light outside the set wavelength range in order to enable image detection by infrared image detection means. filter. 2. The transmittance of infrared light in the set wavelength range is such that the intensity of light incident on the infrared image detecting means is equal to or less than the light intensity at which the output signal of the infrared image detecting means is saturated, and is 1/1 of the saturated state.
2. The infrared cut filter for a film image reading device according to claim 1, wherein the infrared cut filter is set within a range of a light intensity that is equal to or higher than a signal intensity of 2.