WO1997020249A1

WO1997020249A1 - A method for the capture of data and images utilizing a minimum of mechanical activity

Info

Publication number: WO1997020249A1
Application number: PCT/US1996/019067
Authority: WO
Inventors: Harold B. Carter, Jr.
Original assignee: Erudite Technology Iii, Inc.
Priority date: 1995-11-27
Filing date: 1996-11-27
Publication date: 1997-06-05
Also published as: AU1460897A

Abstract

The method for acquiring visual data and images uses an energy source below 400 nm in wavelength or above 700 nm is wavelength and sensors (9) to interrogate a medium (13), multi-stacked media or multi-strata media supported on platform (18) wherein the energy after being focused on a layer (19) is emitted from the media and is collected and stored. Non focused layers of the medium are invisible to the sensors. It is not necessary to move, relative to each other the layers of the medium in order to collect data and/or images from them.

Description

A METHOD FOR THE CAPTURE OF DATA AND IMAGES UTTT.IZING A MTNTMTIM OF MECHANIC AL ACTIVTTY

Inventor: Harold B. Carter, Jr.

BACKGROUND OF THE INVENTION

Field ofthe Invention-

The invention applies to the field of image acquisition, the image compπsmg visual data. The image is acquired from one medium, multiple-stacked media, or multi-strata media of the same, similar or dissimilar molecular structure. Each stratum of each medium is interrogated through the use of a detection device, herein referred to as a capture umt. The capture unit of the mvention detects energy emissions generally, but not necessarily outside the visible range or at wavelengths below 400 or above 700 nanometers of the electromagnetic spectrum (an invisible range of the spectrum is generally considered to have wavelengths below 400 and above 700 nanometers) The capture umt collects the emissions representative of data and/or images from the medium in keeping with the relative difference in level of emissions detected from points where data and/or images appear in the media and where they do not appear Related Background Art ^*

Pnor data and image capture art relies heavily on equipment that employs substantial mechamcal activity Examples are optical character readers ("OCRs"), cameras (operaung inside or outside the visible range of the electromagneuc spectrum), fax machines, copy machines, video cassette recorders ("VCRs"), x-ray machines, MRI machines, CAT scan devices and audio and video tape recorders. The media on which they operate represent any data carrying media. The drawbacks associated with existing image and data capture technology mclude relatively slow operating speed and relatively substantial mechamcal activity. For example, in the instance of printed mateπal, manually or mechanically removing documents and replacing them with the next document contπbutes to frequent failure of the mechamcal equipment necessary to the process. Equipment failure also occurs repeatedly as the result of the accumulation of substances used by such methods or the actual mechanical breakdown of the equipment used.

All current xerographic methods of image capture require the use of a host or transfer medium as an interim step between the capture of the image and its reproduction. Of course, it is known that in the visible spectrum, black or colored print can be differentiated from the surrounding media such as paper and, consequently, images can be captured utilizing this principle but from only one sheet of paper material positioned for imaging at a time. Thus when a stack of paper is copied, each sheet must be separately imaged and mechanically moved to allow the next sheet to be placed in position for imaging. This mechanical activity requires many moving parts, the use of toners and an environment closed to and protected from ambient light. In addition, the electrostatic process used in xerography requires and expends a substantial amount of energy: often Xerox copies are literally hot to touch.

A feature that is not present in the xerographic process is the capability of processing and manipulating the image between the time it is acquired and the time it is reproduced. While optical enlargement and reduction of an image is possible when using some types of xerographic equipment, this capacity is very limited and no xerographic equipment is capable of extensive image manipulation during the transfer of the image to the recipient media.

Currently available facsimile technology is subject to most of the same drawbacks and limitations: it can only image one page at a time; it requires physical movement of the documents being imaged; in some cases, it uses a toner for image acquisition; and many varieties of equipment do not have the ability to manipulate the image electronically or optically after the image is acquired, but prior to its reproduction.

In the case of currently available OCRs, while direct data and image transfer to a computer for electronic processing and manipulation prior to reproduction is possible, the documents from which the data and/or images are being acquired must be physically moved in succession or sequentially for presentation to the OCR. An additional deficiency common to all currently available xerographic, facsimile and OCR equipment is the relatively slow speed with which it operates. Further, no currently available technology embodies, in a single unit, the Xerox and facsimile image acquisition function and the data capturing function of the OCR without moving the documents being interrogated relative to each other. Moreover, such technology fails to provide for simultaneous electronic and/or optic processing and manipulation of the acquired image and/or data prior to its reproduction.

Current imaging and data capture methods are particularly difficult to apply to numerous categories that include both necessary and highly utilitarian fields as well as more esoteric and artistic areas. An example of the former is the copying of mortgage and conveyance records necessary to establish title to real property. In particular, title searches currently involve the laborious task of physically handling volume upon volume of often old and deteriorating county or parish records. The more esoteric and artistic areas include the imaging of records of antiquity such as the Dead Sea Scrolls which can be severely damaged or destroyed by the physical manipulation and handling necessary to present them for copying or imaging by current methods. Another example of an esoteric and artistic area is interactive art such as that of Lynn Hershman's Paranoid Mirror on exhibit at the Seattle Art Museum in Seattle, Washington. U.S. Patent No. 5,099,270 to Pearson et al. is directed to a special object medium having a layered composition of transparent or translucent material. In each layer there is a chemical or chemicals that is subject to change on contact with different electromagnetic wavelengths. With eight layers, an eight bit byte can be stored. Companion apparatus for reading data or geometric images from the disclosed object medium may include a lens. Due to the transparent/translucent layers of the object medium, image capture apparatus or the medium need not be moved in order to accomplish a reading of data stored in the medium. On the other hand, the Pearson et al. invention is limited in its practicality by the specially prepared transparent/translucent nature of the disclosed medium.

Image capture apparatus should not require movement of the layers or sheets of the object medium. Moreover, the object medium should not be required to be specially constructed of specially designed transparent or translucent material. Additionally, the apparatus should not only be useful for capturing visual data from an object medium constructed of opaque material such as printed sheets of paper containing written and printed images and data but should also apply to the interrogation and imaging of other data from object media constructed of other material as well including plastics, metals, cloth and other materials. Thus there remains in the art a need for a more efficient, less intrusive data and image collection method and apparatus.

SUMMARY OF THE INVENTION In view of the drawbacks and limitations of known data and image collection methods discussed above, the present invention provides a method and apparatus for acquiring images of visual data utilizing minimal mechanical activity. For example, the present invention may be used to capture images printed on both sides of sheets of stacked paper by focusing on one side of one sheet at a time. The present invention further provides a method and apparatus for increasing the speed of image and data acquisition and decreasing both the mean time before failure and the mean time to repair the equipment used in the process, for example, by eliminating any need to sequentially move layers of the object media relative to one another. The present invention further provides for reading layered media which is opaque to visible light, such as stacked sheets of printed paper, without having to move the layered media. To appreciate the present invention, reference may be made to the followmg glossary of terms which are given meaning for understanding the following detailed descπption of the mvenuon and appended claims:

A capture umt acquires images of data. A capture unit compπses sensors, a field flattener (optional), optics and filters. The capture unit teπogates each strata of each medium of multi-strata media and sequentially collects emissions from each stratum, the emissions representing each image to be acquired.

An object medium may compπse one medium, multiple-stacked media or mulu-strata media of the same, similar or dissimilar molecular structure. For example, the object medium to be imaged may compπse a book, a magnetic tape, a film or a few sheets of pπnted paper media which are example of opaque media or media which need not be translucent or transparent to visible light. Further, each layer may compπse, for example, a sheet of the book or, more particularly, one side of one sheet of the book if pπnted on both sides of a sheet Importantly, the imaging need not require movement of the book in order to image each side of each page of the book. An object image is an image obtained from one stratum of one medium that is presently bemg focused upon for data acquisition and capture

An image detector is a device, typically a sensor or plurality of sensors, that permits the acquisiϋon of an object image dunng interrogation of an object medium. The image detector may function in an active or a passive mode and it may be shuttered or gated. In an active mode, the capture unit is assisted by a continuous or pulsed energy beam focused on the stratum of the object medium under interrogation In a passive mode, the capture unit functions passively, unassisted by a specifically focused energy beam In this mode, energy may or may not be generally directed towards the object medium under interrogation Consequently, energy may be emitted toward the object medium and diffused, for example, via a slit filter, thus providing a more even distribution of diffuse energy as the energy reaches the layer of the object media to be imaged. Thus, dunng the active mode, the image acquisition occurs via energy transmission toward the media and by collecting reflections or, during the passive mode, image acquisition occurs via energy emission from the media by focusmg on one stratum or layer at a time.

An active energy beam is the energy beams generated dunng an active mode of the present invention Preferably, the active energy beams operate outside the visible region of the electromagnetic spectrum (the visible range of the electromagnetic spectrum occumng at wavelengths between approximately 400 and 700 nanometers). Thus, depending on the object medium under analysis, the invention operates successfully at selected wavelengths selected from a range below 400 nanometers and above 700 nanometers.

In particular, when paper has been the chosen medium under investigation, an energy band selected from within the range of 800 nanometers and four microns is used in one embodiment of the present invention, for example, an energy beam centered at approximately 800 nanometers. At a wavelength selected in this region, a 20 per cent or higher transmissivity is readily achieved. For other media than paper, the energy band may be selected at a wavelength between 5 and 8 microns. While it has been found that at small distances from the object medium, x ray energy provides minimal differentiation between print and sunounding paper, the image differential is improved at greater distances from the object medium. On the lower end of the spectrum, the region below 400 nanometers shows promise for capturing images from printed media.

A reading platform is a support structure upon which the object medium is placed during interrogation and image data acquisition. The platform may or may not have a cover that may be used to physically compress the medium. In this regard, it has been found that compression of a medium such as those comprising a plurality of sheets of paper or a book may be more easily readable if scattering of the electromagnetic emissions from the medium can be reduced by evenly compressing the medium. A further advantage is achieved in that the printed surface is more predictably focused upon when compressed, whether the medium is in the form of reeled media such as film or tape or flat such as printed paper sheets especially when the number of layers of the object medium is less than thirty.

Scattering from the visual data to be imaged in relation to the surrounding media can be detrimental to operation of the present invention. Scattering may be eliminated or reduced, for example, when imaging stacked sheets of paper media by reducing the air gaps between the sheets of paper. Hence, compression of the sheets of paper using a media cover has been found to be useful. A flat planar cover also tends to assure the compressed sheets are likewise as flat or planar as possible during imaging. In one embodiment, the reasonable number of sheets of printed paper that may be imaged without moving the imaged object media is on the order of twenty-five sheets, depending on the thickness of the paper in each sheet.

Undesirable scattering of energy emissions from imaged media can also be reduced by 1) range gating 2) collimation 3) reducing the beam wavelength 4) electronic synchronization 5) honeycomb filters and 6) phase separation or modulation. These techniques will be further discussed herein in connection with the different embodiments of the present invention. The present invention provides a process in which capture units comprised of sensors, an optional field flattener, lenses and one or more filters interrogate and acquire data and/or images from a medium, strata of a medium, layers of a medium or from different strata or media containing the data and/or images without moving the strata or layers of the medium relative to each other. A single detector and moving minor, a staring array or a linear array of capture units may be used in the interrogation and acquisition process.

Focusing on each layer or side of each sheet of stacked media may be accomplished using known focusing techniques. For example, when the medium is layered paper, it has been shown that a focusing arrangement may comprise an objective lens, an afocal lens pair, an imaging ocular lens and finally the detector or sensor described above. The imaging ocular may be used with an image scanning mirror for focusing on a single point detector. In an alternative embodiment, the imaging ocular provides an image to a staring array.

In accordance with the present invention, the staring array or a linear array may operate passively, with or without the use of diffuse energy provided by a generator whose emissions are passed, for example, through a slit filter to permit a relatively even distribution of energy through the medium under intenogation, thereby intensifying the differential between it and the data and/or images to be collected; or, altematively, the operation may be active with the use of continuous or pulsed beams of energy focused on the medium to provide direct reflections or transmissions to the array.

An apparatus operating in the forgoing method in accordance with the present invention includes a platform on which one or a plurality of media to be inteπogated are positioned; capture units for collecting electromagnetic energy emissions of data and/or images from each of the strata of each of the media, and an electronic and/or optical means of processing, storing and or reproducing the data and/or images thus captured. The capture units of the array are focused successively on each strata of each of the media during which process the media not in focus are practically invisible to the emissions from the data and/or images being collected from the strata of the media in focus. The media contained within the plurality are not moved relative to each other.

After the data and/or images are successively acquired from each strata from each media, they may be electronically and/or optically monitored, verified and coπected, processed and manipulated, stored, displayed, communicated and reproduced. In regard to post image capture processing, it may be recognized that data collected from one layer may adversely impact the intelligibility of data collected from the next adjacent layer as the focusing apparatus may not perfectly focus on that layer, for example, one side of a sheet of paper in relation to the opposite or facing side to be imaged next. To reduce or practically eliminate any adverse impact of one layer on another, image subtraction algorithms are useful. After imaging one layer, the image is stored and, as necessary, attenuated and then subtracted from the image captured from the next layer imaged.

If paper is the medium of choice, reproduction may be accomplished through the use of any conventional means including projection, dot matrix, ink jet, and laser jet printers. The data and/or images may also be displayed by currently available devices such as a projector or cathode ray tube.

If film is the medium of choice, then other reproduction equipment known in the art is used for reproducing images captured by the present invention.

Because of the potentially high speed of operation of the current invention, real time reproduction may not be possible when using individual existing printers. It may therefore be necessary to use multiple printing units. If the printing units available are of the type which have a self contained memory, then they may be aligned in series with the data and/or images communicated sequentially to the printing units and directed to each succeeding unit when the memory capacity of the preceding unit has been fully utilized. The apparatus and method according to the present invention may be employed to collect the text from each side of each sheet of a stack of documents (each track of a disc or each layer of a magnetic tape) placed within or upon the reading platform. The text of each document in the stack may be stored, processed as necessary and transfeπed to printing, display and other devices. As a result, the text of the entire stack of documents is acquired, verified and coπected, processed and manipulated, stored, displayed and/or reproduced without the documents ever being moved relative to each other.

Other applications of the present invention are many and varied. Many of these apphcations are described in companion patent applications filed in the United States. Besides paper media, film or magnetic tape may be imaged in similar manner. The present invention may find utility in reading through layers of plastic media such as credit or identification card media. Besides its utility in differentiating data from sunounding media, a further anticipated application of the present invention is in the medical or dental arts for layered imaging of human tissue, bone structure and organs and for diagnosis of medical or mental illness. Further applications include water purification in detecting unwanted material, authenticity of photos, films, oil paintings, water color paintings, also determining underlying painted images, authenticating antiques, and the like, determining if items have been tampered with, fingeφrint authentication, luggage search, vehicle search, building search, and law enforcement generally, quality control of integrated circuits, quality control of drugs, quality control of packaged food, quality control in the pπnting industry, venfying authenticity of currency and other commercial media, detection of termite or other insect infestation and locating faults or blockages in conduits or plumbing. These are but a few of the many potential apphcations of the present mvention. Vanous additional advantages and features of novelty which characterize the mvention are further pointed out in the claims that follow. However for a better understanding of the mvention and its advantages, reference should be made to the accompanying drawings and descriptive matter which illustrate and descπbe preferred embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of this invention, one should refer to the embodiments illustrated in greater detail in the accompanying drawings and described below by way of examples of the mvention.

In the drawings^*

Fig. 1. compπses a perspective view useful for descπbing several embodiments of the invention, each embodiment including an object medium to be intenogated, a lens system for focusmg energy emitted from a focused-upon strata of the object medium and an image detector comprismg a staring array;

Fig.'s 2A, 2B, 2C and 2D provide views useful for descnbing other embodiments of the mvention, for example, Figures 2A and 2B relate to using a linear array as the detector and Figures 2C shows a smgle point detector with an image scanning mirror while Figure 2D shows optics useful m stanng array embodiment.

Fig. 3 shows a flow chart for descnbing the method of image acquisition and storage of some embodiments of the mvention.

Fig. 4 shows some of the functions of the invention.

Fig. 5 shows a sixth embodiment of the present invention involving electronic synchronization of multiple emitters and detectors to alleviate adverse effects of scattering.

It should be understood that the drawings are not necessaπly to exact scale and that certain aspects of the embodiments are illustrated by graphic symbols, schematic representations and fragmentary views. It should also be understood that when referring to physical relationships of components by terms such as "upper", "lower", "upward", "downward", "vertical", "hoπzontal", "left", "πght" or the like, such terms have reference solely to the onentation depicted in the drawings. Actual embodiments or installations thereof may differ. While much mechanical detail, including other plan and section views of the embodiments depicted have been omitted, such detail is not per se part of the present invention and is considered well within the comprehension of those skilled in the art in light of the present disclosure. The resulting simplified presentation is believed to be more readable and informative and readily understandable by those skilled in the art. It should also be understood, of course, that the invention is not Hmited to the particular embodiments illustrated.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE

INVENTION Referring to the figures, wherein like reference characters designate like or corresponding elements of apparatus throughout the views, Figure 1 illustrates a capture unit consisting of sensors 9, an optional field flattener 10, optics 11 and filters 12; an object medium 13 comprising a plurahty of strata or layers, one or more energy emitters 14, their filter assemblies 15, an energy emitter 16, its slit filter 17, a reading platform 18, an object medium cover 18a, data and/or images 19 of an object medium and optional filters 20 which may be housed within the reading platform 18. In Figure 1, the object medium 13 is shown as a stacked collection of documents, it may comprise a book or a collection of stacked sheets of documents printed on one or both sides. Moreover, the medium 13 may comprise paper, film, tape, plastic, metal or other material so long as the capture unit is selected to coUect emissions of compatible frequency (such as near infrared for paper, x ray for plastic) as will be further discussed herein.

Moreover, two or more capture units may be utilized for acquiring an image from a singular object medium or multiple object media 13. Two or more capture units utilized simultaneously and/or in synchronization with two or more energy emitters may provide advantages such as the ability to reduce scattering when focused on a single stratus or to edit or otherwise process a first image of one stratum of an object medium while acquiring an image of another or for comparison with second image data acquired of the same or an adjacent stratum obtained from other capture unit(s). To improve the image captured from one object stratum in comparison with an adjacent stratum or the opposite side of the same stratum, this embodiment may be used in conjunction with an image subtraction processing program which subtracts any image corruption of the object image by the already captured images. According to the present invention, the capture unit 9-12 interrogates the object medium 13 by collecting emissions generally, but not necessarily outside the visible range of the electromagnetic spectrum (generally below 400 and above 700 nanometers) for example, infrared emissions from the data and/or images 19 found at each stratum or layer of the object medium 13. If the medium under scrutiny is paper, a bandwidth selected from the range of 800 nanometers and 3 microns may be preferable, and, in particular, in the vicinity of 1.3 microns. Another promising region is the so-called black light spectrum below 400 nanometers. It has been found that paper in the region between 800 nanometers and 3 microns in wavelength is at least 20% transmissive between sheets of 20 pound weight paper. Xerographic and ink jet print may be differentiated from the surrounding white paper. Also, for other media, another range from which to select a utilization band that has exceptional promise is from 5 to 8 microns. On the other hand and with respect to paper, x ray energy has been shown to exhibit detectable differentiation between print and paper which increases at great distances from the object medium and is also useful for other materials such as polymers.

When the invention is in an active mode of operation, active energy beams from one or more emitters 14 are filtered by a filter 15 and focused on a medium 13 to assist the capture unit 9-12 in collecting data and/or images 19. The active energy beams may be continuous or pulsed and their frequency and amplitude can be varied. The purpose of these focused energy beams is to intensify differential energy emission from object data vis a vis the media it is stored on. The emitted energy provides the capture unit with intensified emissions from data and/or images from each strata of the object medium. When the system is in active operation, the optics 11, filters 12 and 15 and energy emitter 14 are all functioning in mutually compatible frequencies which are also compatible with the sensors 9. Moreover, the focused energy beams generated via emitters 14 are focused to reflect or transmit (depending on the embodiment) the data and/or images from a particular stratum under interrogation 19 at the same time as optics 11 are similarly focused.

The present mvention may also operate passively with the capture unit alone in a passive mode of operation collecting energy emissions from the data and/or images in a selected spectrum or frequency band of interest (generally from a band selected from the range below 400 nanometers and above 700 nanometers in wavelength). However, when it is acquiring data and/or images passively, the capture unit may be helped by non focused energy pulses or constant emissions generated by emitter 16 and passed through slit filter 17 to provide a more even distribution of diffuse energy through medium 13. Also, the emitted energy need not be in the same band as the collected energy. For example, the diffuse energy may be microwave or infrared and the emitted energy collected at the capture unit may be in the infrared or other bands. The differential between the data and/or images being collected and the medium under interrogation is intensified by the diffuse energy. One or more capture units may be configured in a staring or a linear array. Either type of array may be obtained from Fairchild Industπes in California. The staπng array may consist of multiple pixel sensors and/or lensettes in which event a field flattener will not be needed . The puηpose of the optional field flattener 10 is to reduce optical aberrations caused by relatively large lenses. The reading platform 18 and its optional cover 18a for compressing the media to reduce scatter and flatten the object medium may be made of any material and can be invisible, absorbent, and/or reflective, either monopolar or bipolar, or any combination of such properties with regard to one or more bands of the electromagnetic spectrum. The reading platform 18 may also contain sensors 20 which can be obtained from manufacturers such as Fairchild Industπes, Texas Instruments and Kodak. The reading platform 18 may be moved in a vertical or hoπzontal axis (only the vertical axis bemg shown by arrows). Alternatively, the image capture unit and focusing apparatus may be moved to successively capture image data from each layer or stratum of an object medium. The capture umts may be positioned above, below or at any oblique angle with reference to the reading platform. Energy emitters 14 and their filters and housings 15 may also be positioned above or below or at any angle oblique to the reading platform 18, and they need not be positioned in any particular proximity to the capture units of elements 9, 10, 11, 12.

Focus of the optics 11 on vanous strata or layers of the object medium 13 under interrogation may be achieved by varying the focal distance between the capture unit or the object medium through the movement of either the capture unit or the reading platform upon which the object medium is placed or moving both relative to each other. Focus of the optics may also be achieved by varying the back focal distance between the optics 1 1 and the sensors 9 The technology exists to do this automatically and is known to those skilled in the art. The energy beams generated by emitters 14 may also be auto focused on specific layers of the medium as the layers are successively imaged. Optics 11 will be further described and shown with reference to Figures 2C and 2D showing embodiments for imaging a stacked paper target.

Figures 2A and 2B provide further detail of an embodiment of the present invention utilizing a hnear array 209-212 (optional field flattener not present in this embodiment) of sensor detectors 209 located above, normal and/or parallel to the object medium 213 having strata or layers 213A. In Figure 2A, the medium 213 is positioned on a reading platform 206 which may be moved on a single axis perpendicular to the linear array 209-212 which remains stationary. Alternatively, the linear array 209-212 may be moved at a variable distance from the medium 213 and parallel to the medium 213. Figure 2A and Figure 2B each show detectors 208 proximate to lensettes 211 which in turn are positioned proximate to filters 212 operative to filter out emissions from strata or layers, for example, outside the spectrum of interest such as the infrared spectrum. Figure 2B provides an elongated view of the linear array of Figure 2A comprising plural capture unit devices, each comprising similar elements to those depicted as capture unit 9-12 in Figure 1. In particular, Figure 2B shows a linear array 209-212 consisting of plural pixel sensors 209, lensettes 211 and filters 212 for acquiring images focused at varying depths of object medium 213 to strata or layers 213A for collecting emissions from data or images of layer 219.

Referπng briefly to Figure 2A, active or passive beam generation is provided by emitter 214 via filter assembly 215. The emitter 214 may rotate in its longitudinal direction to allow for angular emission with regard to medium 213. Moreover, Figure 2A should not be construed to be limiting as the emitter 214, for example, in a passive mode, may be positioned below the medium 213 to be imaged.

Referring now to Figures 2C and 2D, embodiments for scanning a stacked paper target are depicted involving a single point detector 209a (Figure 2C) and a staring array of sensors 209b (Figure 2D). Stacked paper target 213 comprising layers or sheets 219 is shown at the left (typically a vertical arrangement is preferred). An objective lens 220 follows in the path from the target to either form of detector 209 at the right. After the objective lens is an afocal pair of lenses 222, 223. Finally, an image ocular lens 225 focuses the ouφut of the afocal pair on the image detector 209. In the embodiment of Figure 2C, an image scanning minor 221 is used to focus different portions of the stacked paper target on the single point detector 209a. In the embodiment of Figure 2D, the mirror is not required because a staring array 209b captures points A', B' and C representing points A, B and C of the target, in accordance with the present invention, one layer or side of a sheet at a time.

In particular, objective lens 220 has a depth of focus defined by the principal rays incident on the lens. The lens has a short focal length and maximum diameter in the collecting aperture. The ratio of the focal length to aperture is the "f ' stop or number of the lens which should be as low as possible. Practical designs of corrected optics are available which approach and slightly exceed f/1.0 and have a 50 millimeter or normal field of view. To achieve minimal depth of field, the objective lens is placed at its focal length from the target and the aperture of the objective is fully illuminated by the scattered light which originates there. The afocal lens pair 222, 223 following a Keplerian design functions to gather light collected by the objective so that it may be focused on a suitable detector. As illustrated in Figures 2C and 2D, the rays emitted from points on the target layer produces angular deviation on the back side of the objective. The first lens of the afocal pair 222 gathers these ray bundles and makes them parallel to the optical axis. The second lens 223 of the afocal pair reduces the size of the ray bundles by the ratio of focal lengths (i.e. 0/f2). Thus the parallel bundle of rays from the objective can be made to fit within the entrance pupil of the imagmg ocular 225 without loss of detail. The imaging ocular 225 gathers the parallel ray bundle from the afocal pair and focuses it onto the detector of choice 209. Ocular 225, together with the afocal lens pair 222, 223, provides the magnification required to resolve depth of focus estabhshed by the objective lens 220. In either alternative embodiment of Figure 2C or 2D, magmfication must be adjusted so that the resolved spot on the target coincides with the individual detector size (the single point detector or the pixel size the staring array) to realize resolution (spatial or depth) Diffuse illumination is preferable to promote image capture. If an illuminator has low divergence and if the target provides low scattenng or emissions, insufficient depth of field information provided by the objective may result.

Figure 3 shows a flow chart illustrating an example of the steps of operation of the invention Image acquisition, a novel feature of the present invention, occurs by successively performing steps 302 and 303 once the object medium 13 is positioned on the platform 18 (step 301) Energy emission step 310 is optional depending on the operation of image acquisition in an active mode or a passive mode as descπbed above If the image is to be converted to digital form, step 304 represents such conversion after analog, preferably infrared image acquisition Otherwise, functions as will be descπbed m connection with Figure 4 may be performed via the present invention Continuing down the flowchart of Figure 3, digital data of each layer or side of a layer may be successively captured in CMOS active picture element sensor (APS) arrays known in the art and successively read from memory as each stratum or layer is captured in the CMOS arrays Typically the process proceeds in sequence from the top of the object media to the bottom On the other hand, image data may be read from one selected layer such as page 15 of a 20 page report without moving the report in accordance with the principles of the present invention. If the pnnt is on a reverse side of a sheet, image reversal software (not shown) is used to reverse the image to enhance its accuracy. CMOS APS arrays are known for image capture and available from vaπous Japanese camera manufacturers and have been descπbed by publications authored by Dr. Eπc Fossum and/or Sabnna Kemeny of the NASA Jet Propulsion Laboratory of California. The digital image storage step convemently compπses the steps of successively transfemng the collected digital image data to more permanent memory which may compπse a three dimensional CMOS memory array or other storage of digital data. Image subtraction algoπthms are successively used to process image data from one layer or side of a sheet to the next as required (not shown).

At certain frequencies, it is not practical to perfectly focus on one layer without detecting image data of the previously stored adjacent layer or other side of the same layer or sheet. The already captured data is simply attenuated and subtracted from the corrupting effect it has on the object layer, leaving the object layer data according to image overlay and subtraction algoπthms known m the art. Then the process repeats as per steps 306, 307, 308 and 309, the iterative process of steps 302, 303, 304 and 305.

In a prototype test, paper copies made through Xerography and ink jet pπnted paper exhibited pπnt which was easily differentiable from the sunounding paper Layers proved to be up to 20% transparent With unage subtraction algoπthms, a number of pages of prmted paper of 20 pound stock may be imaged without movement of the sheets of paper.

Figure 4 illustrates the basic operating functions of the invention The capture umt of the present mvention operates to acquire images of an object medium and this function is designated 401. After the capture unit function 401 has been performed and the data and/or images collected, they are transmitted electronically and/or optically to one or more of the other functions 402-6

There are six basic functions veπfication and correction 402, processing and mampulation

403, storage 404, display 405, communication 406, and signal tracing 407 of the data and/or images

19, 219 and their path to and from every function to which they are directed and/or subjected and the separate storage of a non-erasable, permanent record of the signal tracing Function 408 represents acoustic and/or visual reproduction of an image

Veπfication and conection 402 will normally be the first function to which the data and/or images are passed It is the purpose of this function to veπfy the accuracy of the captured data and/or images and to coπect enors that are discovered dunng the veπfication process One of the greatest propensities for eπor exists in the instance of captuπng pnnted data when the document under interrogation is pπnted on both sides of each page and the contents of the document are repetitive as in music or poetry. The initial veπfication process in such cases will usually consist of a compaπson of the pπnted opposing or facing lines on one such page with those on the other. This method is similar to a combination of some of the underlymg processes used by programs that check spelling and grammar, and proximity word and phrase search programs Other more sophisticated techniques may be used if necessary The correction methods utilize relatively straight forward manipulation processes. Processing and manipulation 403 allows the user to select an almost limitless variety of combinations and permeations including among many others: enlarging and compacting including the formatting and configuration of the data and/or images from numerous pages on a single page, conversion from one print style to another, segmenting of handwritten and printed materials, the addition of information such as Bates numbers, sorting by text content into multiple categories, translation from one language to another, conversion from printed or handwritten data and/or images, conversion from alpha-numeric to graphic form, conversion from analog data and/or images to digital, conversion from digital data and/or images to analog. In sum, the processing and manipulation function 403 may utilize alone or in combination all types of manipulation and processing permitted by the current state of this art.

Storage 404 may be accomplished at any stage of any of the other Optional Functions. All known storage media may be used singly or in combination. The storage unit 404 may be located in close proximity to the intenogation and capture unit 401 and/or the other functional units 402-7 or it may be at a distance from any one or all of them. There may be one or several storage units. The same is true of each of the function units with regard to physical location and number of units. The display function 405 may consist of any available means of displaying visual data/images in any combination. The communication function is for use in transmitting data/images at any stage from any function to one or more functions at a different location or to any form of data/image reproduction equipment. The signal tracer 407 has many uses. It contains an internal clock, and it can be programmed to add to any reproduction of data and/or images their history from the time of their capture to the time of their reproduction. It can also be programmed to send to the end user's accounting department the cost of each use of the invention.

One embodiment of the invention consists of a staring array located above or below and parallel to the medium 13 which is placed for intenogation on the reading platform 18 that can be moved on a single axis perpendicular to the staring array which remains stationary in this embodiment. The medium 13 is moved at a variable or constant speed through the focal distance of the optics 11. The data and/or images 19 are intenogated by capture unit 9-12 operating at a fixed or variable frequency and/or amplitude. The data and/or images thus acquired can be subjected to any combination of the six functions: verification and correction, processing and manipulation, storage, display, communication, and reproduced visually 408. Precision focus of the optics can be accomphshed by existing auto- focusing technology. One stanng array embodiment for a paper target is shown in Figure 2D.

In another embodiment of the invention (detail being shown in Figures 2 A and 2B), a linear array of capture units replaces the stanng array while the other facets of the invention remain the same. The stanng array in conjunction with optics will provide focus by varying the back focal distance of the optics and stanng array.

In a third embodiment of the mvention, either the hnear array or the stanng array is positioned so that the capture units 9-12 are at an angle oblique to the honzontal axis of the medium thereby captunng the data and/or images at an oblique angle. In a fourth embodiment of the invention, the medium remains stationary and the hnear or stanng array is moved so as to vary the distance between the array and the medium dunng data and/or image acquisition. The position of the capture units may be either above or below and perpendicular or oblique to the medium in this embodiment Focus of optics can be by electromagnetic focusmg devices. In a fifth embodiment of the invention, the capture units in a hnear array are moved honzontally above or below and parallel or oblique to the object medium In this embodiment, the data and/or images can be captured either in successively deeper layers dunng each of a senes of hnear scans by the array or the capture of the data and/or images in the successively deeper layers of the medium may be accomplished by one hnear movement of the array dunng which the focus and/or object distance of the capture units is vaned so as to scan through the enure mass of the object medium dunng a smgle sweep of the array.

In a sixth embodiment of the invention, multiple emitters are located above and normal to the media bemg intenogated and multiple capture units are located below and normal to said medium. Referring to Fig. 5, the emitters 14 and capture units 9 are configured so that the emissions are in the form of an hourglass and radiate from an arcuate emitter assembly 14 toward an arcuate collector assembly 9. The ob_ject medium is at the center point of the hourglass. The same function is achieved here by electronically synchronizing the emitter/collectors as range gating to interrogate the object medium 13 which may be moved a vertical and horizontal axis by moving platform 18. This embodiment permits the interrogation of the entirety of each strata of the medium by multiple synchronized emitters 14 and capture umts 9.

The molecular structure and configuration of both the gross mass of the medium and of the data and/or images that are to be intenogated and captured are factors to be considered in selecting the most useful embodiment of the invention. Other factors include the purpose of the data and/or image acquisition, the nature and extent of post-capture subjection of the data and/or images to the functions, the volume of data and/or images to be interrogated and captured, whether the capture will be selective of different types or forms of data and/or images present in the medium and the operating speed of the functions to which the captured data and/or images will be subjected.

Additional consideration must be given to the capabilities of the peripheral devices available for reproduction of the acquired data and/or images. For example, the operating speed of currently available printing equipment may not permit real time transfer to a single printing unit for reproduction. This issue may be resolved in some cases through the use of multiple printing units. If the printing units available are of the type which have a self-contained memory, then they may be aligned in series with the data and/or images communicated sequentially to the printing units and directed to each succeeding unit when the memory capacity of the preceding unit has been fully utilized.

Resolution of the issue of the speed of operation of the peripheral units may be deferred if transmission of the data and/or images is from one computer to another or, for instance, in the case of a fax from a computer to a fax machine with a self-contained memory. If speed of reproduction is a primary concern, then self-contained memory type fax machines may be aligned in series for data and/or image reproduction in a manner similar to the alignment of the printing units described above.

It will be understood that the details, materials and arrangements of parts of specific embodiments have been described and illustrated to explain the nature of the invention. Changes may be made by those skilled in the art without departing from the invention as expressed in the appended claims.

Claims

1. An apparatus for sequentially acquiring data and/or images from an object medium comprising multiple strata or layers without movement or manipulation of the strata or layers relative to each other by sequentially collecting emissions from each stratum or layer of said object medium, the apparatus comprising a platform for supporting and positioning said object medium to be imaged and a capture unit for acquiring data and/or images from each stratum or layer of said object medium, said data and/or images collected from electromagnetic emissions in a selected band of frequencies selected from a range of frequencies below 400 nanometers and above 700 nanometers in wavelength from each stratum or layer of said object medium to be imaged, said image capture unit including a lens for sequentially focusing said non-visible emissions from each stratum or layer of said medium.

2. An apparatus according to claim 1 wherein said capture unit further includes a filter.

3. An apparatus according to claim 1 wherein said capture unit further includes a field flattener.

4. An apparatus according to claim 1, further comprising an emitter for emitting a beam of non-visible electromagnetic radiation focused on each stratum or layer of said medium as said data and/or images are collected from each of said strata or layers.

5. An apparatus according to claim 4 further comprising a filter interposed between said emitter and said object medium.

6. An apparatus according to claim 1, further comprising an emitter for emitting diffused non-visible electromagnetic radiation, thereby intensifying the differential between the data and/or images and said object medium.

7. An apparatus according to claim 6, further comprising a slit filter for diffusing emissions from said emitter.

8. An apparatus according to claim 1 wherein said capture unit is located above said platform and said platform further comprises a separate capture unit, said object medium being located between said platform and said capture unit above said platform.

9. An apparatus according to claim 1, said capture unit further comprising a storage unit for storing said data and/or images.

10. An apparatus according to claim 1, wherein said capture unit is configured as a staring array.

11. An apparatus according to claim 1 , wherein said capture unit is configured as a linear array.

12. An apparatus according to claim 1, wherein one stratum and a next succeeding stratum to be imaged comprise planar sheets of said object medium.

13. An apparatus according to claim 1, wherein said non-visible electromagnetic emissions are infrared emissions.

14. An apparatus according to claim 6, wherein said diffused beam comprises a band of frequencies in the vicinity of 800 nanometers in wavelength.

15. An apparatus according to claim 1, wherein said platform is in a plane perpendicular to said capture unit.

16. An apparatus according to claim 1, wherein said object medium comprises composite materials which are opaque in the visible spectrum.

17. An apparatus according to claim 16, wherein said object medium is further configured as stacked planar medium with minimal air gaps between layers.

18. An apparatus according to claim 18, wherein said object medium comprises ten sheets of printed paper and said apparatus further comprises a medium cover for compressing said object medium.

19. An apparatus according to claim 1, wherein said image capture unit comprises an active pixel sensor array.

20. A method of interrogating an object medium comprising multiple strata or layers without movement or mampulation of the strata or layers of the object medium relative to each other, the method comprising the steps of positioning said object medium on a platform and sequentially focusing on each stratum or layer of said object medium and collecting a selected band of electromagnetic emissions from the range of frequencies below 400 nanometers and above 700 nanometers in wavelength from each stratum or layer of said object medium focused upon.

21. The method of claim 20 wherein said electromagnetic emissions are infrared.

22. The method of claim 20 further comprising the step of generating a diffuse non-visible electromagnetic radiation directed toward said object medium.

23. The method of claim 20 further comprising the step of generating a beam of non-visible electromagnetic radiation focused on each stratum or layer as emissions are collected.

24. The method of claim 20 further comprising the step of imaging a stacked planar medium of paper material with air gaps between sheets and compressing said object medium using a medium cover to minimize the air gaps and flatten stacked planar medium.

25. The method of claim 20 wherein said band is selected within the range between soft x ray and hard ultraviolet.