JP3545522B2 - Image input lens device and method of correcting focus position - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention is applicable to an image input device such as a photoprinting device and an image recording device, and a document setting position for setting a support for supporting a film document and a mounting position of an image sensor for photoelectrically reading a film document image are provided. For imaging optics fixed at a fixed distancePutThe present invention relates to an image input lens device and a method of correcting a focus position thereof.
[0002]
[Prior art]
At present, printing of an image photographed on a photographic film manuscript (hereinafter, referred to as a film manuscript or simply a film) such as a negative film or a reversal film onto a photosensitive material such as photographic paper is performed by projecting the image of the film manuscript onto the photosensitive material. It is performed by so-called direct exposure, which exposes the photosensitive material to the surface.
[0003]
On the other hand, in recent years, printing apparatuses that use digital exposure, that is, photoelectrically read image information recorded on a film, convert the read image into a digital signal, and then perform various image processing on the image for recording. Digital photo printers for printing and printing images (latent images) by scanning and exposing a photosensitive material with recording light modulated in accordance with the image information are being developed.
[0004]
Digital photo printers are also free to edit layouts of print images, such as editing multiple images, dividing images, editing characters and images, and various image processing such as color / density adjustment, scaling, and edge enhancement. It is possible to output the finished print freely edited and image-processed according to the application. Further, in conventional printing by direct exposure, it is not possible to reproduce all image density information recorded on a film or the like in terms of density resolution, spatial resolution, color / density reproducibility, etc. For example, a print in which almost 100% of the image density information recorded on the film is reproduced can be output.
Further, according to the digital photo printer, it is possible to store (save) image information of an image recorded on each film and image processing conditions for the image information in an external memory such as a memory or a floppy disk of the apparatus. Therefore, when performing additional printing or the like, a film serving as an original image is not required, and since there is no need to set processing conditions again, operations such as additional printing can be performed quickly and efficiently.
[0005]
Such a digital photo printer is basically an image input device that reads an image recorded on a document such as a film, a setup device that performs image processing on the read image to determine exposure conditions for image recording, and It comprises an image recording apparatus that scans and exposes a photosensitive material in accordance with exposure conditions and performs development processing.
The present applicant has proposed image reading apparatuses and methods for realizing such a digital photo printer in Japanese Patent Application Laid-Open Nos. 6-217091, 6-233052 and 6-245062, and In this publication, an outline of a digital photo printer device is disclosed.
[0006]
[Problems to be solved by the invention]
By the way, in such an image input device, a film original is loaded on a support such as a carrier and attached to a predetermined position, illuminated with a light source from the back side, and transmitted light carrying an original image transmitted through the film original is transmitted through a lens. An image is formed on an image sensor such as a CCD by a device, and a document image is read photoelectrically.
An image input device for inputting such a film original image is required to have high definition and excellent color reproducibility, and be capable of supporting various film sizes and applications such as trimming. Required.
[0007]
In order to satisfy such requirements, it is conceivable to use a zoom lens as a lens device. However, in the above-described image input apparatus, the mounting position of the carrier on which the film original is mounted and the mounting position of the image sensor are fixed, and the distance between the film original and the lens unit and the distance between the lens unit and the image forming surface are determined. The distance to the CCD is limited. The lens device used in such an image input device is required to have considerably high imaging performance including strict chromatic aberration correction.
In order to satisfy these requirements, it is preferable to use a special optical material such as fluorite or high-refractive-index low-dispersion glass for the lens. However, such an optical material has a problem that a change in the refractive index due to temperature is larger than that of other optical materials, and a change in a focus position (focusing position) is increased.
[0008]
On the other hand, there are various types of film originals that are targeted in such an image input apparatus.
For example, as a film form, a long film in which a large number of images called so-called strips (sleeve) such as a normal 135 negative film or a reversal film are taken, and one film (sometimes a reversal film) There is a slide fixed to a slide mount every time. Therefore, the strips are sandwiched between a film holder and a film carrier and are installed at the mounting position, and the slides are loaded on the slide holder and the slide carrier and installed at the mounting position.
However, in the case of slides, the thickness of the mount serving as the film support is not constant, and varies depending on the type of mount, for example, materials such as paper and plastic, film manufacturing companies or developing laboratories. In addition, there is a problem that the position of the film original surface fluctuates, and it is necessary to adjust the focus according to the type of slide. Also, strips have a curl usually called curl, and it is necessary to adjust the focus according to the state of curl of the film.
[0009]
Meanwhile, an automatic focus determination device for a general camera that performs temperature compensation of the focus position of an imaging lens using the above-described optical material is disclosed in Japanese Patent Application Laid-Open No. 58-111005, and is used for a camera for plate making. A focus position temperature compensating device is disclosed in Japanese Patent Application Laid-Open No. 3-87801.
However, the automatic focus determination device disclosed in Japanese Patent Application Laid-Open No. 58-111005 is intended for a general camera, and is intended for a device in which the distance between the subject and the imaging lens greatly changes. , The focus position is assumed to be the focus position, so the focus accuracy is coarse, and high-resolution, high-precision image reading in which the curl state of the strips of the film original, the thickness of the slide support, etc. becomes a problem. Has a problem that it cannot be applied at all.
The focus position temperature compensating device disclosed in Japanese Patent Application Laid-Open No. 3-87801 is used for a plate-making camera, and can adjust a focus position shift due to a temperature change of an imaging lens. The distance relationship between the object, the imaging lens, and the imaging surface is calculated from the focal length of the lens according to a predetermined arithmetic expression, and the imaging lens is adjusted to the best focus position based on the calculation result. However, there is a problem that the curl state of the strips and the difference in the thickness of the slide support cannot be adjusted.
[0010]
SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and to enable high-precision image reading corresponding to a wide variety of film originals. In particular, it is possible to automatically adjust the focus position shift due to the curl of the strips and the thickness change of the slide support, and the focus position shift due to the change of the focal length due to temperature change, and always focus on the best focus position. It is an object of the present invention to provide a lens device for image input that can be performed and a method of correcting the in-focus position thereof.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, a first aspect of the present invention is a method for photoelectrically reading an image carried on a film original by an image sensor fixed at a predetermined distance from a document installation position for holding the film original. For image opticsPutAn image input lens device,
A zoom lens group that moves in accordance with a reading magnification according to the carried image of the film original, a zoom motor that drives the zoom lens group,
A focus lens group that focuses on the image sensor an image carried on the film original that has been scaled by the zoom lens group according to the reading magnification; and a focus motor that drives the focus lens group.,
A temperature sensor that detects the temperature of at least one of the zoom lens group and the focus lens group;
Movement data of the focus lens group up to a focus position measured for a plurality of magnifications at a reference temperature with respect to a reference document set at the document setting position, the reference temperature data, and a temperature from this reference temperature Means for storing, in advance, movement correction amount data of the focus lens group measured in advance,
From this storage means, the focus lens group obtained by reading out the movement amount data corresponding to the reading magnification and the movement correction amount data based on the difference between the temperature detected by the temperature sensor and the reference temperature, and adding them. According to the film original, centering on the in-focus positionAutomatically determine focus positionMeans for setting the movement range of the focus lens group for
Automatic focus adjustment means for automatically controlling the focus motor so as to automatically move the focus lens group to a focus position within the movement range according to the film documentThe present invention provides an image input lens device having the following.
[0012]
According to a second aspect of the present invention, there is provided an image forming optical system which photoelectrically reads an image carried on a film document by an image sensor fixed at a predetermined distance from a document installation position for holding the film document.Put, Having a zoom lens group and a focus lens groupFor image inputWhen automatically setting the lens device to the in-focus position,
Movement data of the focus lens group up to a focus position measured for a plurality of magnifications at a reference temperature with respect to a reference document set at the document setting position, the reference temperature data, and a temperature from this reference temperature With the change, the movement correction amount data of the focus lens group measured in advance isRemember in advance,
A film document is set at the document setting position, and the temperature is measured by a temperature sensor while moving the zoom lens group together with the focus lens group to a reference position corresponding to the reading magnification,
The movement amount data of the focus lens group according to the reading magnification and the movement correction amount data based on the difference between the measured temperature and the reference temperature are read from the storage unit, and the movement correction amount data from the measured temperature to the reference temperature are read out. Are read and added to calculate the calculated focusing position, and the moving range of the focus lens group is set around the calculated focusing position,
The focus lens group is moved to the calculation focus position, and this position is centered.The focus lens groupWithin the movement rangeAutomatically move to focus positionIt is another object of the present invention to provide a method of correcting the in-focus position of the image input lens device.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An image input lens apparatus and a method of correcting a focus position according to the present invention will be described in detail below based on preferred embodiments shown in the accompanying drawings.
[0014]
FIG. 1 is a schematic perspective view (a control unit 21 is shown in a block diagram) of an embodiment of an image input device to which an image input lens device for implementing the focus position correcting method of the present invention is applied.
An image input device (hereinafter, referred to as an input device) 10 shown in FIG. 1 is a long negative film or a reversal film, and a frame A, which is usually a strip reversal film on which a large number of images are photographed. This is a device for photoelectrically reading images taken on these film originals by using a slide B fixed to (mount) as a film original, and basically includes an optical frame 12, a light source unit 14, a carrier base 16, An imaging unit 18 in which the lens device of the present invention is incorporated, an image sensor 20 as an area sensor, a control unit 21 including control means for the lens device of the present invention, and a film carrier 22 which can be mounted on the carrier base 16; Having.
[0015]
In the input device 10, the film carrier 22 mounted on the carrier base 16 conveys the strip A in the direction indicated by the arrow x in the drawing, stops at the reading position Z, and irradiates the light from the light source unit 14 on the film document image. Then, projection light carrying an image photographed on a film original is obtained, the projection light is formed on the image sensor 20 in the image forming section 18, and the image sensor 20 performs photoelectric conversion to obtain an image signal. By subjecting the signal to image processing in the control unit 21, an image photographed on a film original is two-dimensionally read as an image signal.
[0016]
The light source unit 14 is uniformly diffused enough to irradiate the film document (strips A) so that the image sensor 20 can separate the film document image into three primary colors of R, G, and B and read it with high accuracy. It produces each color light with a large amount of light.
FIG. 2 is a schematic diagram of the light source unit 14.
In the input device 10 of the illustrated example, the light source unit 14 irradiates the strips A from below to obtain projection light, and is located below the carrier base 16 of the optical frame 12, and is provided with a light source 25, a reflector 25a, a stop 26, It has a color filter plate 28 and a diffusion box 30.
In addition, a cooling fan or the like for cooling various members such as the light source 25 is disposed in the light source unit 14.
[0017]
As the light source 25, various known light sources that can emit a sufficient amount of reading light for image reading by the image sensor 20 can be used, and examples thereof include a halogen lamp, a xenon lamp, and a mercury lamp.
The aperture 26 adjusts the amount of light from the light source 25. In the illustrated example, the stop 26 has a logarithmic curve drawn at the light-shielding portion and has two different passing amounts of light in the direction of the arrow a perpendicular to the optical axis L in the figure. By using the ND filters 26a and 26b and moving the ND filters 26a and 26b toward and away from each other in the direction of arrow a, the light amount from the light source 25 to the film is adjusted.
[0018]
The color filter plate 28 is a disc-shaped member having three color filters of an R (red) filter 28R, a G (green) filter 28G, and a B (blue) filter 28B. It is configured to be rotatable by rotating means.
At the time of image reading, the R filter 28R, the G filter 28G, and the B filter 28B are sequentially inserted into the optical path L, whereby the image captured on the film is separated into three primary colors of R, G, and B and read.
[0019]
The diffusion box 30 emits light from the light source 25, the light amount of which is adjusted by the diaphragm 26, diffuses the reading light that has passed through the color filter, and sets the light amount and the like of the reading light incident on the film in the film surface direction, that is, with the optical axis L. This is for making the surfaces orthogonal to each other uniform without unevenness.
In the illustrated example, the diffusion box 30 has a configuration in which diffusion plates are arranged on the upper and lower surfaces of a quadrangular prism whose inner surface is a mirror surface, but various other known light diffusion means can be used.
The light source unit 14 may be provided with a shutter for blocking light emitted from the light source unit 14 as needed.
[0020]
As shown in FIG. 1, a carrier base 16 is arranged above the light source unit 14.
The carrier base 16 is a part on which the film carrier 22 is mounted and held at a predetermined position, and is fixed vertically to the optical frame 12. An opening (not shown) through which light from the light source unit 14 passes is formed in a portion corresponding to the optical axis L in the carrier base 16. In addition, the size of the opening is set to a size that can sufficiently irradiate the entire surface of the maximum size of the image read by the input device 10 with the light from the light source unit 14 according to the maximum size of the film read by the input device 10. Good.
[0021]
Guide rails 34 and 36 are formed on the upper surface of the carrier base 16 in the direction from the near side to the optical frame 12 in the drawing, that is, in the direction of the arrow y perpendicular to the direction of the arrow x which is the transport direction.
Further, grooves 38 and 40 are formed on the bottom surface of the film carrier 22 so as to correspond to the guide rails 34 and 36.
That is, the position of the film carrier 22 placed on the upper surface of the carrier base 16 in the direction of the arrow x is defined by the guide rails 34 and 36 and the corresponding grooves 38 and 40, respectively. The position in the direction of the arrow y is defined by contact with the end face on the far side in the figure, and the carrier is positioned and mounted at a predetermined position on the carrier base 16.
[0022]
According to the input device 10 of the present invention having such a configuration, by pushing or pulling out the film carrier 22 in the direction of arrow y, the two can be easily exchanged and mounted at a predetermined position on the carrier base 16. can do. Therefore, it is possible to read the images photographed in the respective strips A in a suitable manner.
The means for mounting the film carrier 22 or the like at a predetermined position on the carrier base 16 is not limited to a method using such a guide rail and a groove or the like engaging with the guide rail. It is also possible to use a part, a contact member that engages with each other, various types of clamp members, suction by a magnet, or the like.
[0023]
As described above, the film carrier 22 is configured to be freely mounted on the carrier base 16 of the input device 10 in the illustrated example.
The film carrier 22 transports a long negative film or a reversal film, which is a so-called strips (sleeve) A, on which a large number of images have been taken, in the longitudinal direction thereof, and transfers each image taken on the strips A to the optical axis L. The sheet is sequentially conveyed to an upper predetermined position, that is, a reading position Z corresponding to an opening of the carrier base 16 (not shown), and is provided for reading.
[0024]
The groove 38 corresponding to the guide rail 34 of the carrier base 16 and the groove 40 corresponding to the guide rail 34 are formed on the bottom surface of the main body 46 of the film carrier 22 as described above.
Further, a guide groove 48 is formed on the upper surface of the main body 46 so as to extend from one end to the other at a position intersecting the optical axis L in the transport direction indicated by the arrow x. The guide groove 48 is a groove having substantially the same width as the strips A. The strips A are conveyed while being inserted in the guide grooves 48 so that their longitudinal directions coincide with the x direction, and each image is sequentially Is transported to the reading position Z on the optical axis L. Therefore, the depth of the guide groove 48 is set so that the image surface (that is, the emulsion surface) of the strip A is located at a predetermined position in the optical axis L direction (the depth of focus direction).
[0025]
Further, an opening through which reading light from the light source unit 14 passes is formed at the reading position Z of the main body 46 of the film carrier 22. This opening also serves as a mask that regulates light input to the image of the strips A. For example, if the strips A has a size of 135, the openings have a size and shape corresponding thereto. When the film carrier 22 is arranged at a predetermined position on the carrier base 16, the reading position Z is naturally a predetermined position on the optical axis L, that is, a position corresponding to the opening of the carrier base 16. is there.
Further, the opening formed in the main body 46 of the film carrier 22 may have a size corresponding to the opening of the carrier base 16 so that masks corresponding to films of various sizes can be exchanged and mounted on the film carrier 22.
[0026]
In the guide groove 48, the transporting means 50 for the strips A, the film pressing unit 52, and the screen detection sensor 54 are arranged from upstream to downstream in the x direction.
The conveying means 50 is composed of a motor 56 and a conveying roller 58. The conveying means 50 conveys the strips A in the direction of the arrow x according to the detection result of the screen detection sensor 54, stops when the image reaches the reading position Z, When a signal indicating the end of reading is received from 21, conveyance is started again, and the next image is conveyed to the reading position Z.
The film crimping unit 52 corrects the curl or the like of the strip A by pressing the strip A into the guide groove 48 at the reading position Z at the time of reading the image, and fixes the entire surface of the image at a predetermined position in the direction of the optical axis L, that is, document setting. It is held in position. Such a film crimping unit 52 includes a crimping member 60 and rotating means 64 for rotating the crimping member 60 about the shaft 62 in the direction of arrow b. At times, it is pivoted upward by the pivoting means 64 and pivots downward at the time of reading to press the strip A at the reading position Z. At a position corresponding to the reading position Z of the crimping member 60, an opening 60a through which the projection light of the strip A passes is formed.
The screen detection sensor 54 is a known optical sensor, and detects an image or a DX code taken in the x-direction upstream of the reading position Z of the strip A, thereby detecting the position of the image at the reading position Z. Is defined. In the illustrated film carrier 22, the transport of the strips A by the transport unit 50 is controlled according to the detection result of the screen detection sensor 54 so that each image is sequentially stopped at the reading position Z. To hold and release the strips A.
[0027]
The transport of the strips A in the film carrier 22 and the operation of the film pressing unit 52 are not limited to those controlled automatically using the screen detection sensor 54 or the like as in the above-described example, but are performed semi-automatically or by an operator. The rotation of the crimping member 60 and / or the stop / drive of the transport unit 50 may be performed manually.
[0028]
In the illustrated input device 10, a film carrier 22 and a slide carrier 24 for automatically (semi-automatically) transporting the strips A and the slide B to the reading position Z are loaded on the carrier base 16 of the optical frame 12. The present invention is not limited to this. Instead of the film carrier 22, for example, as shown in FIG. 3, a carrier body 66 having grooves 42 and 44 for engaging with the guide rails 34 and 36 of the carrier base 16 is provided. And a slide carrier 24 that automatically or semi-automatically transports the slide B to the reading position. As a carrier of the film original, in addition to the film carrier 22 and the slide carrier 24, an opening for transmitting light from the light source unit 14 is formed at the reading position Z, and a groove that engages with the guide rails 34 and 36. In the case of a film original carrier having a main body formed with a mark, even if the operator is a manual carrier for fixing the strips and slides at a predetermined position, the operator arranges the film or slide at an arbitrary position and reads. It may be a trimming carrier or the like.
[0029]
The slide carrier 24 shown in FIG. 3 holds a film on which an image has been captured in a frame, conveys a so-called slide B in the direction of the arrow x, stops at the capturing position Z, performs image reading, and performs reading. The collected slides B are collected.
[0030]
As described above, the groove 42 corresponding to the guide rail 34 of the carrier base 16 and the groove 44 corresponding to the guide rail 34 are formed on the bottom surface of the main body 66 of the slide carrier 24. The slide carrier 24 is mounted on the carrier base 16 in the same manner as the film carrier 22 so that the rear side of the paper in FIG.
On the upper surface of the main body 66, a guide groove 68 that guides the slide B is formed extending from the end to the end in a position intersecting with the optical axis L in the conveyance direction of the slide B indicated by the arrow x. You. The depth of the guide groove 68 is set so that the image plane of the slide B is substantially at a predetermined position in the optical axis L direction (depth of focus direction).
Further, in the main body 66 of the slide carrier 24, an opening also serving as a mask similar to that of the film carrier 22 is formed at the reading position Z so that light from the light source unit 14 passes therethrough. Note that, similarly to the film carrier 22, a mask may be separately provided so as to be replaceable according to the size of the slide B.
[0031]
A cover 70 is arranged near the reading position Z on the upper surface of the main body 66.
The cover 70 is a housing having an open bottom surface on which a through hole 72 through which the projection light of the slide B passes is formed on the upper surface, and covers the reading position Z during normal reading. It is configured to be rotatable about the axis in the direction of arrow c, and the reading position Z can be opened as required.
[0032]
FIG. 4 is a schematic plan view near the reading position Z with the cover 70 opened.
In the vicinity of the reading position Z, the guide groove 68 is slightly wider, and a sensor S1 for detecting the slide B near the entrance and a sensor S2 for detecting the tip of the slide B conveyed to the reading position Z in the arrow x direction are provided. Further, on each side of the wide portion of the guide groove 68, six rollers for transporting the slide B are respectively arranged.
The rollers on the upper side in the figure are conveying rollers 74 of the slide B, and are rotated at a predetermined speed by a driving source (not shown).
The lower rollers are driven rollers 76, 76... The driven roller 76 is rotatably supported at the tip of an arm 80 that is rotatable about a fulcrum 78, and the arm 80 is urged toward the transport roller 74 by a spring 82. Therefore, the slide B is pressed against the transport roller 74 by the driven roller 76, is suitably nipped between the two, and is reliably transported, and the rotation of the arm 80 supporting the driven roller 76 absorbs the size difference of the slide B. can do.
Further, at the reading position Z, a slide holder 84 is arranged as needed. The slide holder 84 is configured to be rotatable by rotation of a shaft 86 by a driving source (not shown), and at the time of reading, presses the slide B against the guide groove 68 at its tip (the tip opposite to the shaft 86), thereby causing the slide B to slide. Correct the distortion and lifting of (the frame).
[0033]
A slide collection box 88 for collecting the slide B for which reading has been completed is disposed downstream of the cover 70 in the direction of the arrow x.
The illustrated slide collection box 88 is configured to house the slide B so as to be sunk under the already collected slide B, and the slides B that have been read are sequentially stacked from below and collected. You. In addition, in the present invention, the slide collection box 88 may be a box or the like that accommodates the slide B dropped by the pushing of the slide B conveyed later.
[0034]
In the illustrated slide carrier 24, the operator manually supplies the slide B along the guide groove 68 to the position of the sensor S1.
When the slide B is detected by the sensor S1, the transport rollers 74 rotate to transport the slide B to the reading position Z, that is, the position detected by the sensor S2, and stop.
When the image reading is performed at this position and a signal indicating that the reading has been completed is received from the control unit 21, the conveying rollers 74, 74... Start conveying again, and the slide B is stored in the slide collection box 88. .
[0035]
On the upper part of the optical frame 12, an image forming part 18 constituting the lens device of the present invention is arranged.
The imaging unit 18 includes a lens unit 92 vertically mounted on a surface plate 90 fixed to the optical frame 12, a zoom motor 93, a focus (focus adjustment) motor 94, and a temperature sensor 95. The projection light of A and slide B is imaged on the image sensor 20.
The lens unit 92 changes the magnification in accordance with the size of the strips A and the slide B, and changes the magnification of the projection light to the maximum size that can be received by the image sensor 20 (that is, the longest portion of the required image area is the image sensor). A zoom lens group 96 incorporating a known zoom lens for adjusting the size to a size inscribed on the light receiving surface of the light receiving surface 20 and forming an image on the image sensor 20, and a zoom lens group 96 located above (downstream in the optical axis L direction). And a focus lens group 98 in which a known focus adjustment lens for adjusting the focus of the projection light on the light receiving surface of the image sensor 20 is incorporated. The adjustment gear 96a of the zoom lens group 96 is meshed with a drive gear 93a rotated by a zoom motor 93, and the zoom lens group 96 controls the light so that the image size on the image sensor 20 according to the magnification is adjusted. The movement is adjusted in the direction of the axis L. Further, the adjustment gear 98a of the focus lens group 98 meshes with the gear 94a rotated by the focus adjustment motor 94, and the focus of the focus lens group 98 is adjusted by the focus adjustment motor 94, that is, the focus lens group 98 is moved to the in-focus position. Is done.
The driving of the motors 93 and 94 is controlled by the automatic focus adjustment unit 104 of the control unit 21, and the input device 10 in the illustrated example is obtained by being read by the image sensor 20 by a TTL (Through The Lens) method. The automatic focus adjustment (autofocus: AF) is performed using the image and its contrast, and the in-focus position correcting method of the present invention is performed. This will be described in detail later.
The temperature sensor 95 is for detecting the temperature of each of the lens groups 96 and 98 of the lens unit 92, and a temperature detector such as a thermistor is attached to the lens barrel of the lens unit 92 near the lens glass material. The temperature measurement value of the lens unit 92 measured by the temperature sensor 95 is used by the control unit 21 to correct the change of the focal position of the focus lens group 98 of the lens unit 92 due to the change of the lens temperature, that is, the change of the in-focus position. It is transmitted to the focus adjusting means 104.
[0036]
The projection light of the strips A and the slide B is imaged on the image sensor 20 by the lens unit 92, and is read photoelectrically. A known shutter used for dark current correction or the like may be arranged between the lens unit 92 and the image sensor 20.
In the input device 10 that performs two-dimensional image reading, the image sensor 20 is an area sensor, for example, a CCD sensor having 1380 × 920 pixels. In the illustrated example, the image sensor 20 is configured to be movable in the x direction and the y direction by an amount corresponding to a half pixel, whereby the number of read pixels can be apparently increased to four times. .
[0037]
A signal from the image sensor 20 is output to the control unit 21.
The control unit 21 receives an output signal from the image sensor 20, performs predetermined image processing, and outputs the image information as image information. The control unit 21 controls not only the image processing operation of the image processing apparatus 100 but also the image input device. The CPU 102 controls the components and the whole of the zoom lens group 98, and performs a calculation for setting a search area for determining a focus position of the lens apparatus of the present invention. The movement amount data (reference pulse (number) given to the focus motor 94) from the home position (HP) of the focus lens group 96 to the reference focus position at the reference temperature at each position, the reference temperature data, and the reference temperature. The movement correction amount data of the focus lens group 96 according to the temperature change (the temperature correction amount given to the focus motor 94). Memory 103 for storing data of the amount of movement of the zoom lens group 98 from the home position (HP) (pulses (number) given to the zoom motor 93) according to the reading magnification, and the image sensor 20. And an automatic focus adjustment unit 104 that performs automatic focus adjustment using the read and obtained image. Further, the control unit 21 is connected with a keyboard 106 and a mouse 108 for inputting operation (input) setting of reading (output) conditions such as a reading magnification, a display 110 for displaying an image read by the image sensor 20, and the like. You.
[0038]
FIG. 5 is a detailed block diagram of one embodiment of the control unit 21. In the control section 21, the CCD 20 is connected to a CPU bus via a movement control circuit 20a in the xy direction for performing a pixel shift for apparently increasing the number of read pixels. Image information read by the CCD 20 is input to the image processing device 100. In the image processing apparatus 100, the analog image data read by the CCD 20 is converted into digital image data by the A / D converter 111, the DC offset is corrected by the offset correction circuit 112, and then the dark correction circuit 113 Correction is applied. After that, it is LOG-converted by the LOG conversion circuit 114, and is subjected to shading correction by the shading correction circuit 115, and then stored in the frame memory 116 and output to the image recording apparatus P or the like.
[0039]
The image data corrected in darkness by the darkness correction circuit 113 is input to the automatic focus adjustment means 104, and in the automatic focus adjustment means 104, first, the focus position (focus position) determination circuit 118 determines a predetermined search area as described later. The image contrast integrated value of each point in is obtained, and the position where this value is maximum is determined as the in-focus position. The information on the in-focus position is transmitted from the in-focus position determining circuit 118 to the motor drive control circuit 119 for controlling the motors 93 and 94 of the lens unit 92 via the CPU bus.
On the other hand, from the temperature sensor 95, the measured temperature value is transmitted from the carrier type discriminating means 120 to the information as to whether the film carrier 22 for strips A or the slide carrier 24 for slide B is loaded, and the keyboard 106, Using the mouse 108, information such as reading conditions such as reading magnification is input to the CPU 102, the memory 103, the focusing position determination circuit 118 of the automatic focus adjustment unit 104, and the motor drive control circuit 119 via the CPU bus.
[0040]
The light source 25, aperture (iris stop) 26, and color filter plate 28 of the light source unit 14 are respectively controlled by a light source control circuit 25b, an aperture control circuit 26c, and a color filter control circuit 28b connected to the CPU 102 via a CPU bus. The light intensity, aperture, and type of color filter are controlled.
By the way, the control section 21 may be provided with a positive / negative conversion circuit 117 for performing a positive / negative inversion on image information on which predetermined image processing has been performed by the image processing apparatus 100. When the strips A and slide B are reversal films, the positive / negative conversion circuit 117 converts the image information on which predetermined image processing has been performed before outputting it to the output device P, and converts the image information into a negative image (or vice versa). ). The method of positive-to-negative conversion or negative-to-positive conversion is not particularly limited, and may be a known conversion method (image processing method).
The discrimination of whether the strips A or the slide B is a negative film or a reversal film may be input by an operator, or may be performed by the apparatus based on a read image or a film form. Alternatively, both may be configured to be selectable.
[0041]
Meanwhile, in the image input device shown in FIGS. 1 to 5, a lens unit 92 having a zoom lens group 96 and a focus lens group 98 of the image forming unit 18, a zoom motor 93, a focus motor 94, a temperature sensor 95, and The CPU 102 for calculating the focus position determining circuit 118, the motor drive control circuit 119, the memory 103, and the predicted focus position of the automatic focus adjustment means 104 of the control unit 21 and setting a search area for focusing is provided by the present invention. Construct a lens device.
As described above, the image input device to which the lens device of the present invention is applied is basically configured.
[0042]
As is well known, in a normal input device, prior to reading an image for output, an image taken on a film is roughly read (rough) to set a main subject and determine reading conditions. A can is performed.
In the input device 10 of the illustrated example, as described above, the image processing device 100 receives the output signal from the image sensor 20 in the pre-scan, sets the image processing conditions, and sets a book (fine) for the output image. At the time of scanning, according to the set image processing conditions, a predetermined image processing is performed on an output signal from the image sensor 20, and the image signal is output to an image recording device (output device) P or the like as image information. It is configured by combining known image processing circuits for setting image processing conditions and performing various types of image processing.
[0043]
On the other hand, as described above, the automatic focus adjusting unit 104 moves the zoom lens group 96 of the lens unit 92 to a predetermined position according to the type of the film original and the reading magnification before the pre-scan, and then performs the temperature control according to the present invention. The focus lens group 98 is moved and adjusted by the focus motor 94 within the predetermined search area set by the CPU 102 in consideration of the temperature change of the lens unit 92 measured by the sensor 95, and the film original is moved at each position in the search area. The image is read, the image contrast is calculated, the in-focus position is determined, and the focus lens group 98 is moved to the in-focus position by the focus motor 94, thereby performing automatic focus adjustment (auto focus).
[0044]
The input device 10 in the illustrated example is a device capable of reading images of film originals having completely different shapes, ie, strips A and slides B. Therefore, the lens device of the present invention can accurately and appropriately input images of these film originals. This device is capable of forming an image in the area of the CCD 20 in size. A normal film has a curl, and the film surface is curved, but the state of the curl is not uniform and varies depending on the film. Further, the slide B often has a different thickness depending on the manufacturer and specifications, and furthermore, may have a slight curl or distortion while being held by the frame. In other words, in a lens device corresponding to various originals, the image plane differs in the direction of the optical axis L depending on the type of the slide B and the state of the films of the strips A and the slide B.
For this reason, in the lens apparatus of the present invention, the zoom lens group 96 is used, and the focus lens group 98 can be moved independently of the zoom lens group 96, and the focus lens group 98 is provided with the above-described automatic focus adjustment function. Therefore, even if the image plane fluctuates in the optical axis direction, the automatic focus adjustment can be performed to always perform stable and accurate image reading with the same appropriate reading size, so that the operator Is simplified, and quick and accurate image reading can be realized.
[0045]
FIG. 6 shows a flowchart of an example of the focus adjustment of the lens device of the present invention in the input device 10.
First, the automatic focus adjustment unit 104 reads out the number of pulses corresponding to the moving amount of the zoom lens group 96 from the memory 103 according to the reading magnification by the motor drive control circuit 119, and applies the number of pulses to the pulse motor 93. Then, the zoom lens group 96 is moved to a position corresponding to the reading magnification. At this position, a required read image area (predetermined setting area) of the film original (strips A, slide B) forms an image on almost the entire sensor area of the CCD 20, more precisely, an area slightly smaller than the entire sensor area. The zoom position. Here, when printing a film original such as a strip A or a slide B such as a negative film or a reversal film, generally, not all the images recorded (carried) on the film original are reproduced. The image size to be printed and reproduced with respect to the carried image size is strictly set. For this reason, in the input device 10, the image size of the film original to be imaged on the entire area of the CCD 20 using the lens device of the present invention having a zoom function is strictly matched to a predetermined set size. .
[0046]
Next, the automatic focus adjustment unit 104 receives the determination result of the carrier mounted on the carrier base 16 and the temperature measurement result of the temperature sensor 95, and implements a later-described in-focus position correcting method of the lens apparatus of the present invention. A predicted focus position (a position predicted to be the best focus) is calculated according to whether the film original to be read is strips A or a slide B, and a search area (a range for searching for the best focus position) centering on this position is calculated. Set. The search area may be, for example, a predetermined focal length range centered on a normal focal length, and is determined in advance corresponding to the type of film original (or carrier). The determination of the carrier mounted on the carrier base 16 may be configured so that the CPU 102 or the automatic focus adjustment unit 104 automatically determines the carrier in accordance with the mounting of the carrier on the carrier base 16. Alternatively, the input may be performed using the mouse 108.
In parallel with the setting of the search area according to the present invention, the G filter 28G of the color filter plate 28 is inserted into the optical path L by the control circuit 28b in the light source unit 14.
[0047]
After the search area is set by the method of the present invention, the motor control circuit 119 of the automatic focus adjustment unit 104 applies a predetermined pulse to drive the focus adjustment motor 94 to start the search, for example, the initial position, for example, in the search area. The focus lens group 98 is moved to a position where the focal length becomes the shortest. Next, projection light carrying an image (G image) emitted from the light source 25, passed through the G filter 28G, and passed through the film original is read by the image sensor 20, and an image of the film (G image) is read. .
The output signal from the image sensor 20 is sent to the image processing device 100, subjected to predetermined image processing such as A / D conversion, offset correction, darkness correction and the like, and sent to the automatic focus adjustment unit 104 as image information. . Thereafter, the focus position determination circuit 118 of the automatic focus adjustment unit 104 calculates an image contrast integrated value from the obtained image information, that is, integrates a MTF (Modulation Transfer Function) in a predetermined spatial frequency region in the read image. Calculate the value.
The operation of the image reading and the calculation of the image contrast integrated value is performed from the initial position of the search area to the end position of the search area, that is, from the initial position of the search area to the state where the focal length is longest in the search area in this case. Each time the focus lens group 98 is moved by a predetermined distance (in this case, the focal length is increased) while the focus adjustment motor 94 is driven by the motor control circuit 119 of 104, the process is repeated at each position. Here, the movement of the focus lens group 98 may be continuous or intermittent.
[0048]
After the image contrast integrated value in the search area is completed, the focus position determining circuit 118 of the focus adjustment unit 104 detects the position where the image contrast integrated value is the largest as the focus position, and the motor control circuit 119 sets the focus adjusting motor. The focus lens group 98 is set to the in-focus position by driving the 94, and the focus of the projection light is accurately adjusted to the light receiving surface of the image sensor 20.
[0049]
Note that, in the lens device of the present invention, the method of automatically adjusting the focus is not limited to this. For example, the distance between the film surface and the image sensor 20 is measured by a photoelectric method or a trigonometric method, and the focus is adjusted. Various known focus adjustment methods such as a method can be used.
[0050]
Next, a method of correcting the in-focus position of the lens device of the present invention will be described with reference to FIGS.
As shown in FIG. 7, the lens apparatus of the present invention for implementing the focus position correcting method of the present invention includes a lens unit 92 including a zoom lens group 96 and a focus lens group 98, and a zoom motor 93 as described above. , A focus motor 94, a temperature sensor 95, a CPU 102, a memory 103, and an automatic focus adjustment unit 104 including a focus position determination circuit 118 and a motor drive control circuit 119.
[0051]
First, prior to the start of use of the image input device 10 in which such a lens device is incorporated, for example, a reference glass chart is used as a film original at the time of factory shipment, and at a reference temperature, at each reading magnification (that is, according to each reading magnification). The in-focus position of the zoom lens group 98 (for each moving position) is detected by performing the above-described automatic focus adjustment method, and the CPU 102 provides the reference moving amount (the motor 94) of the focus lens group 96 from the home position (HP). The reference pulse is calculated and stored in the memory 103 together with the reference temperature data. At this time, the temperature is changed by a predetermined amount from the reference temperature, the focus position is similarly obtained using the same reference glass chart, and the difference from the focus position at the reference temperature, that is, the movement correction amount (temperature correction pulse) ) Is obtained by the CPU 102 for each reading magnification, and is stored in the memory 103 together with the temperature change. This process is performed at a predetermined interval for a predetermined temperature range that can be used, and the memory 103 stores, for each reading magnification, reference movement amount data and reference temperature data, and a required number of movement correction amount data and temperature data. Let it be.
[0052]
Next, a carrier (film carrier 22 or slide carrier 24) is mounted on the carrier base 16 according to the film original (strips A or slide B) on the input device 10, and the film original A or B from which an image is to be read is placed on the carrier 22. Alternatively, the film original A or B is placed at a predetermined original installation position.
Here, prior to the pre-scan for reading the image of the film document A or B, the method of correcting the in-focus position of the lens device of the present invention is performed as follows.
[0053]
{Circle around (1)} First, the zoom lens group 96 and the focus lens group 98 of the lens unit 92 of the lens device of the present invention are at the home position (hereinafter referred to as HP), and the reading magnification and the film original (carrier) type are transmitted to the CPU 102. It is assumed that the temperature measured value of the lens unit 92 by the temperature sensor 95 is also input to the CPU 102 via the automatic focus adjustment unit 104.
[0054]
{Circle around (2)} First, the CPU 102 reads, from the memory 103, data on the amount of movement of the zoom lens group 96 (the number of pulses to be applied to the zoom pulse motor 93) from the HP according to the type of film original and the reading magnification.
{Circle around (3)} The automatic focus adjustment means 104 receives the data from the CPU 102, rotates the zoom motor 93 by the number of pulses (movement amount) read from the memory 103, moves the zoom lens group 96, and sends the data to the CCD 20. The size of the original image is exactly matched with the read size of the CCD 20.
[0055]
{Circle around (4)} The CPU 102 stores the data (see FIG. 8) of the movement amount (focus reference pulse (number)) of the focus lens group 98 from the HP at the set reading magnification according to the carrier type (film original) type. Read from
(5) After that, the CPU 102 calculates a temperature difference between the temperature measured value obtained by the temperature sensor 95 and the reference temperature stored in the memory 103, and from this temperature difference, the movement correction amount of the focus lens group 98 ( The temperature correction pulse (number)) data (see FIG. 8) is read from the memory 103, and as shown in FIG. 8, the reference pulse and the temperature correction pulse are added to reach a predicted focus position which is the center of the search area. , The movement amount calculation value (predicted focusing pulse (number)) data from the HP is calculated.
{Circle around (6)} As shown in FIG. 8, the CPU 102 sets a search area around the calculated predicted focus position according to the film document type and the reading magnification.
[0056]
{Circle around (7)} Thereafter, as shown in FIG. 8, the CPU 102 calculates data of the movement amount (start point pulse (number)) from the HP to the start point of the search area, that is, the initial position, and transmits the data to the automatic focus adjustment unit 104. .
{Circle around (8)} The automatic focus adjustment unit 104 receives the data from the CPU 102, rotates the focus motor 94 by the number of start point pulses (movement amount), and moves the focus lens group 98 to the start point of the search area.
[0057]
(9) Thereafter, the automatic focus adjustment means 104 and the CPU 102 perform the automatic focus adjustment according to the flowchart shown in FIG. 6 to obtain the in-focus position (best focus position) and focus on the in-focus position as described above. The lens group 98 is located.
Thus, the in-focus position correcting method of the lens device according to the present invention is completed.
[0058]
The lens device of the present invention and the method of correcting the in-focus position thereof are basically configured as described above. Hereinafter, the operation of the input device 10 to which the lens device of the present invention is applied will be described in detail. I do.
First, a carrier is mounted on the carrier base 16 according to the form of the document to be read, that is, whether the document is strips A or slide B. Here, assuming that the strips A are read, as shown in FIG. 1, the grooves 38 and 40 of the film carrier 22 are engaged with the guide rails 34 and 36 of the carrier base 16 to place the film carrier 22 thereon. Then, the film carrier 22 is pushed in the direction of the arrow y to a position where the rear end surface of the film carrier 22 comes into contact with the optical frame 12, and is mounted on a predetermined position on the carrier base 16. Note that a means for holding the film carrier 22 mounted at a predetermined position may be provided on one of the optical frame 12 and the film carrier 22 (slide carrier 24).
Further, when the strip A is a reversal film, an instruction to that effect may be given using the keyboard 106 or the mouse 108.
[0059]
After it is confirmed that the light amount from the light source unit 14 has reached a predetermined value, the pressing member 60 of the film pressing unit 52 is lifted upward, and the first image photographed on the strip A is positioned at the reading position Z. Thus, the strips A are loaded into the film carrier 22, and an instruction to start reading is issued.
In the input device 10 of the illustrated example, when an instruction to start reading is issued, first, as described above, the method of correcting the in-focus position of the lens device according to the present invention is performed. Automatic focus adjustment is performed based on the contrast of the obtained image, and the focus adjustment motor 94 is driven to adjust the focus lens group 98 to the in-focus position.
When the focus adjustment is completed, a pre-scan is then started. As described above, since the focus adjustment is performed by inserting the G filter 28G and reading the G image, the pre-scan is started in that state, and the light modulated by the G filter 28G passes through the strip A. Then, the projection light carrying the image is formed on the image sensor 20 by the lens unit 92, the G image of the document is read, and sent to the control unit 21. When the reading of the G image is completed, the color filter plate 28 rotates, for example, the R filter 28R is inserted into the optical path L, and the reading of the R image is performed in the same manner. And the pre-scan ends.
[0060]
In the control unit 21, the image obtained by the pre-scan is displayed on the display 110, and the setting of the main subject is performed as necessary. In the image processing apparatus 100, the obtained image information and the main subject are displayed. Accordingly, reading conditions such as the aperture amount of the aperture 26 of the light source unit 14 and image processing conditions are determined.
[0061]
When the reading conditions and the image processing conditions are determined, and the focus adjustment, the adjustment of the aperture 26, and the like are completed, the main scan is started.
When the main scan is started, similarly to the pre-scan, the G filter 28G is inserted into the optical path L, the light modulated by the G filter 28G is transmitted through the strip A, and the projection light is imaged by the lens unit 92. The image is formed on the sensor 20, the G image of the document is read, and sent to the control unit 21, and thereafter, the R image and the B image are read in the same manner and sent to the control unit 21.
The image processing device 100 of the control unit 21 performs predetermined processing such as A / D conversion on the output signal from the image sensor 20 and outputs the signal to the image recording device P as image information for output. When the strip A is a reversal film, the image information from the image processing apparatus 100 is sent to the positive / negative conversion circuit 117, and is output to the image recording apparatus P after the positive image information is converted into the negative image information. Is done.
[0062]
When the first image reading is completed in this way, a signal to that effect is output from the control unit 21 to the film carrier 22, the pressing member 60 rotates upward to release the strip A, and then the conveying unit 50 Drives to transport the strips A in the direction of the arrow x, stops transporting according to the detection result by the screen detection sensor 54, and transports the next image to the reading position Z.
Next, the crimping member 60 is rotated downward to fix the strip A, and reading is performed in the same manner as above.
[0063]
When the reading of the strips A is completed and then the reading of the slide B is performed, the film carrier 22 shown in FIG. 1 is detached from the carrier base 16 and the slide carrier 24 shown in FIGS. Attach to. After the confirmation of the light amount or the like is completed as in the case of the strips A, the slide B is manually supplied along the guide groove 68 as described above, and when the slide B is detected by the sensor S1, the transport rollers 74, 74,. , The slide B is transported to the reading position Z detected by the sensor S2, the focus position correcting method of the present invention is performed in the same manner as in the reading of the strip A, the focus is adjusted, and the pre-scan and book Scanning is performed, and the image on slide B is read.
When the controller 21 receives a signal indicating that reading has been completed from the controller 21, the transport rollers 74 start transporting again, and store the slide B in the slide collection box 88.
[0064]
As described above, the image input lens device of the present invention and the method of correcting the in-focus position thereof have been described in detail. However, the present invention is not limited to this, and various types may be used without departing from the gist of the present invention. Of course, changes and improvements may be made.
[0065]
【The invention's effect】
As described in detail above, according to the present invention, the type, shape, and form of a film original such as a strip or slide, for example, a change in the thickness of the curl of the film or slide or the thickness of the support of the slide and a change in temperature. By adjusting the fluctuation of the image reading size formed on the image sensor by the above, it is possible to form an image to an accurate image size, and also automatically adjust the focus position shift due to the change of the film original form and the temperature change, It is always possible to focus on the best focus position. As a result, according to the image input device using the lens device of the present invention, high-precision image reading can always be performed with an appropriate image size.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view of an embodiment including a block diagram of a control unit of an image input device to which an image input lens device according to the present invention is applied.
FIG. 2 is a schematic perspective view of one embodiment of a light source unit of the image input device shown in FIG.
FIG. 3 is a schematic perspective view of one embodiment of a slide carrier mounted in place of the film carrier of the image input device shown in FIG.
FIG. 4 is a schematic plan view showing an embodiment near the reading position of the slide carrier shown in FIG.
FIG. 5 is a block diagram of an embodiment of a control unit of the image input device shown in FIG.
FIG. 6 is a flowchart for explaining automatic focus adjustment in the image input device shown in FIG. 1;
FIG. 7 is a schematic diagram illustrating a lens device according to the present invention.
FIG. 8 is an explanatory diagram illustrating a method of correcting the in-focus position of the lens device according to the present invention.
[Explanation of symbols]
10 Image input device
12 Optical frame
14 Light source
16 Career Base
18 Imaging unit
20 Image sensor
21 Control unit
22 Film carrier
24 slide carrier
25 light source
26 Aperture
28 color filter plate
30 Diffusion box
34, 36 guide rail
38, 40, 42, 44 grooves
46,66 body
48,68 Guide groove
50 conveyance means
52 Film crimping unit
54 Screen detection sensor
56 motor
58, 74 Transport roller
60 crimping member
62,86 axes
64 rotating means
70 Cover
72 Passage hole
76 Idol Roller
78 fulcrum
80 arm
82 Spring
84 Slide Hold
88 Slide collection box
90 surface plate
92 Lens unit
93 Zoom motor
94 Focus motor
95 Temperature sensor
96 zoom lens group
98 Focus lens group
100 Image processing device
102 CPU
103 memory
104 automatic focus adjustment means
106 keyboard
108 mouse
110 display
118 Focusing Position Determination Circuit
119 Motor drive control circuit

Claims (2)

An image input lens device in an imaging optical system for photoelectrically reading an image carried on the film original by an image sensor fixed at a predetermined distance from a document installation position for holding a film original,
A zoom lens group that moves in accordance with a reading magnification according to the carried image of the film original, a zoom motor that drives the zoom lens group,
A focus lens group that focuses on the image sensor a carried image of the film original that has been scaled by the zoom lens group according to the reading magnification; and a focus motor that drives the focus lens group.
A temperature sensor that detects the temperature of at least one of the zoom lens group and the focus lens group;
Movement data of the focus lens group up to a focus position measured for a plurality of magnifications at a reference temperature with respect to a reference document set at the document setting position, the reference temperature data, and a temperature from this reference temperature Means for storing, in advance, movement correction amount data of the focus lens group measured in advance,
From this storage means, the focus lens group obtained by reading out the movement amount data corresponding to the reading magnification and the movement correction amount data based on the difference between the temperature detected by the temperature sensor and the reference temperature, and adding them. Means for setting a movement range of the focus lens group for automatically determining a focus position according to the film document around the calculated focus position,
Automatic focus adjustment means for automatically controlling the focus motor so as to automatically move the focus lens group to a focus position within the movement range in accordance with the film document. Lens device. A zoom lens group and a focus lens group used in an imaging optical system that photoelectrically reads an image carried on the film document by an image sensor fixed at a predetermined distance from a document installation position for holding the film document; When automatically setting the image input lens device to the in-focus position,
Movement data of the focus lens group up to a focus position measured for a plurality of magnifications at a reference temperature with respect to a reference document set at the document setting position, the reference temperature data, and a temperature from this reference temperature With the change, the movement correction amount data of the focus lens group measured in advance is stored in advance,
A film document is set at the document setting position, and the temperature is measured by a temperature sensor while moving the zoom lens group together with the focus lens group to a reference position corresponding to the reading magnification,
The movement amount data of the focus lens group according to the reading magnification and the movement correction amount data based on the difference between the measured temperature and the reference temperature are read from the storage unit, and the movement correction amount data from the measured temperature to the reference temperature are read out. Are read and added to calculate the calculated focusing position, and the moving range of the focus lens group is set around the calculated focusing position,
Moving the focus lens group to the calculation focus position, and automatically moving the focus lens group to the focus position within the movement range around this position. A method for correcting the in-focus position of the lens device.

Images