INFORMATION SCANNER PROVIDING TWO
SEPARATE DIGITAL IMAGES OF A WRITTEN
The present invention relates to information scanning apparatus and more particularly, but not exclusively to portable information scanning apparatus.
The present invention has been made from a consideration of the problems associated with studying large 10 volumes of documents. Documents are often studied whilst travelling or at home rather than at the workplace. When items of interest are found, scribbled notes may be made in the margins of the documents. Having made the notes the readei seldom has time to store the IS information in a manner suitable for easy retrieval.
EP 0142967 discloses an apparatus for scanning readable information. A guide sheet is placed on the document and the scanner head runs along a track in the guide sheet reading the information. Timing marks are 20 provided on the guide sheet adjacent the track for generating timing signals having a frequency proportional to the speed of travel of the scanner head. The combination of ruler and timing marks provide scanner information in a geometrical and consistent coordinate frame. 25
The present invention seeks to provide a portable scanning apparatus which may store information without the need for a track or timing marks. The invention will prove particularly useful to users who have to read large volumes of printed information and need to re- 30 member and note document references, pages or keywords.
According to the present invention there is provided an information scanning apparatus for scanning human interpretable information, said apparatus comprising at 35 least one image receiving means adapted to scan said information, wherein the image receiving means is adapted to provide at least one digital image of said information and the apparatus further comprises a stability device, the stability device providing a bearing 40 surface for the user to apply pressure to the information to be scanned.
By using the stability device improved scanning is achieved. The apparatus should be able to cope with variations in scanning speed, text quality, text size and 45 attitude of the scanning head. Otherwise this will result in distortions. However these variations are reduced to a considerable extent by the use of the pen which introduces an element of control feedback to the operation.
In a preferred embodiment of the invention the image 50 receiving means provides two different digital images of said information. No supplementary direction, distance or speed measuring device is required. The two different images are preferably images which are relatively physically displaced. The two effectively physically 55 displaced images may be extracted from an image presented to an area imaging camera. These images may be obtained by suitable arrangement of two individual imaging cameras such as linescan cameras provided in the scanning apparatus. Alternatively two adjacent 60 coherant linear light guides present their views to a linescan camera whereby each individual image can be discriminated from the other. Alternatively one light guide may provide an image for each camera. The end of the light guide which faces the camera may be illumi- 65 nated by way of a light source in such a manner as not to reflect direct light into the viewing camera which is arranged to collect light reflected from the text at the
other end of the light guide. The stability device may comprise a pen or brush. This stability device may be provided adjacent the image receiving means. Ink from the stability device may make a permanent mark of what information has been scanned. The image receiving means may comprise two viewing elements which preferably are mounted in the image receiving means in such a manner that they are not rotatable relative to one another and/or axially rotatable about the viewing axis. Means for axial translation of the image receiving means including the viewing elements may be provided in the device. Resilient means such as a spring may resist this movement.
At least one digital image is normalised and passed to the input of a text recogniser. Here the text characters are converted to computer codes. These may then be subject to any of the following: storage, manipulation, offloading and conversion onto a human interpretable format.
In order that the invention may be more readily understood a specific embodiment thereof will now be described by way of example only with reference to the accompanying drawings in which:
FIG. 1 is a side elevation of a scanning head in accordance with the invention;
FIG. 2 is a second side elevation of the scanning head of FIG. 1;
FIG. 3 is a plan view of the screen of the scanning apparatus of FIGS. 1 and 2; and
FIG. 4 is a block diagram showing the scheme of operations of the scanning apparatus partly illustrated in FIGS. 1 to 3.
Referring to the drawings an information scanner comprises a scanner head 10 connected to a portable computer 12.
The scanning head 10 comprises two viewing elements 14,16 the free ends 18,20 of which when in use are run over the text to be stored. The viewing elements 14,16 are mounted in the scanning head 10 by way of a mounting 22. The mounting 22 comprises an outer casing 24 and an inner sleeve 26. The sleeve 26 and casing 24 may have angular features in order to assist in restricting the rotation of the viewing elements 14,16 with respect to the casing. A flange 28 is provided at the topside of the sleeve 26 which is urged towards the upper end 30 of the casing 24 by a coil spring 32. In this way the viewing elements 14,16 are mounted such that axial rotation relative to the viewing axis and radial rotation with respect to the casing 24 are restricted. However rotation in the axis of the viewing line of the viewing elements 14,16 and axial translation along the principal axis of the viewing elements 14,16 against the force of the spring 32 are not prevented. The viewing elements 14,16 are therefore mounted in such a manner as to provide a wide range of suitable relative angles between the text and the scanning head during which the text can be read.
An ink marking brush or pen 34 is adapted to provide a light transparent mark on the text. The brush or pen 34 is secured to the side of the casing 24. The direction of the nib of the pen 34 is parallel to the direction of the visual elements 14,16. The nib of the pen 34 preferably comprises a smooth shaped bearing of material such as P.T.F.E. that does not damage the material being scanned. Pens 34 known as highlighter pens are particularly suitable.
The pen 34 acts as a stabilising device to improve the accuracy of the scanner when scanning a line of text.