WO2002006916A2

WO2002006916A2 - Reading aid for the blind

Info

Publication number: WO2002006916A2
Application number: PCT/IL2001/000463
Authority: WO
Inventors: Yishay Langenthal
Original assignee: Yishay Langenthal
Priority date: 2000-07-18
Filing date: 2001-05-22
Publication date: 2002-01-24
Also published as: AU2001260583A1; WO2002006916A3; IL137343A0

Abstract

In accordance with this invention there is provided a compact hand-held portable reading aid (10) for the blind that receives data in electronic form and outputs said data in Braille readable form. The data receiving means may be, for example, an optical scanner (10) or a wireless telephone that can receive facsimile and/or internet communications. Electronic circuitry (32) receive and convert electronic data, which according to this invention are translated and outputted to an active Braille readable display (20).

Description

READING AID FOR THE BLIND

The present invention relates to a reading aid for the blind. In particular the invention relates to a hand-held portable device useful for blind people to read electronic input data. More specifically, the invention particularly concerns a hand-held scanner of record media having an output readable by a blind person.

BACKGROUND OF THE INVENTION

The prior art discloses a number of devices that translate lines of text to Braille. One such device available is the Power-Braille 40 of TeleSensory, Mountain View CA., USA. Another, is the INKA keyboard of Baum Products GmbH, Wiesenbach, Germany. These devices are limited to translating only text. The DMD 120060 dot matrix display of Metec, Stuttgart, Germany, translates an entire visual display so that it can be read by touch. However, this device is slow because it translates an entire display at the same time. All these devices are relatively cumbersome and are suitable as desktop units only. US Patent 5,912,660 describes a mouse-like input/output device for use with a computer display screen. The mouse has a display readable by blind people. This display has pins that move up and down that can be felt with the finger-tips to provide tactile representation of data from the screen.

Hand-holdable scanners are known for a number of applications, such as for bar code readers and for recording data from documents for reproduction, translating or other form of processing. Some of these applications are disclosed in US Patents 4,393,460; 4,523,235; 4,639,790; 4,890,230; 4,947,261; 4,959,871; 5,063,508 and 5,301,243. Recent publications WO97/01827 and WO98/03932 describe a hand-held portable optical scanner useful as an electronic translator of record medium. The device has a visual display, optical scanner and rotary position detector. Such a device is now available commercially under the name Quicktionary.

OBJECT OF THE INVENTION

It is an object of the present invention to provide a self-contained hand-held portable reading aid for the blind having means for receiving data and outputting said data in readable form for the blind.

It is a further object of the present invention to provide a self-contained hand-held portable reading aid for the blind for scanning record medium and outputting it in readable form for the blind.

Another object of the present invention to provide a self-contained hand-held portable optical scanner that converts text data into Braille readable form.

Still another object of the invention is to provide a self-contained hand-held portable optical scanner that converts non-text record data into Braille readable form.

Yet another object of the invention is to provide a self-contained hand-held portable reading aid for the blind having means for inputting electronic data and outputting said data in readable form for the blind. SUMMARY OF TH INVENTION

In accordance with this invention there is provided a compact hand-held portable reading aid for the blind that receives data in electronic form and outputs said data in Braille readable form, comprising: a rigid hand-held portable elongated housing that can be held with one hand between the thumb and fingers like a pencil, said housing having a top end and a bottom end, means for receiving data in electronic form, a data processor for processing received data and translating it into Braille signals, and an active Braille display mounted on the housing responsive to the Braille signals.

Data receiving and translating means as such are known, and these may be used in the present invention. However, the application of these means in a hand-held compact portable housing with a specifically located active Braille display is novel and inventive. The data receiving means may be, for example, an optical scanner or a wireless telephone that can receive facsimile and/or internet communications. These means receive and convert electronic data, which according to this invention are translated and outputted to an active Braille readable display.

An important feature of the reading aid, which is basically an electronic translator for blind people, is the positioning of the active Braille display on the housing, whereby the reading aid can be held in a hand with the fingers accustomed to reading Braille positioned on the active Braille display. The active Braille display is, therefore, preferably located on a side of the housing, and is preferably comprised of moveable pins that are raised and lowered in response to electronic signals enabling the user to read the scanned and converted information whether it be originally in text or graphic patterns. Alternatively, the Braille display may have static pins responsive to electronic signals that deliver electric impulses that can be felt by fingers touching the pins.

In a preferred embodiment of the invention, the hand-held reading aid comprises:

An optical scanner including a scanner head for scanning a record media; illuminating means for illuminating record media; an optical sensor for sensing information on the record medium; focusing lens for focusing light reflected from the record medium to the optical sensor and for producing an output corresponding thereto; an active Braille display; and a data processor for processing the output of the optical sensor and translating this into Braille readable form; the data processor being programmed to first measure the output of the optical sensor when the scanner head is out of contact with the record medium to assure the output is below a first predetermined threshold, and then to measure the output of the optical scanner when the scanner head is in contact with the record medium to assure that the output is above a second predetermined threshold, before it processes the output of the optical sensor.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is herein described, by way of example only, with reference to the accompanying drawings, wherein:

Fig. 1 illustrates a hand-held reading aid in use, according to the present invention;

Fig 2 is a diagrammatic side view illustrating the internal construction of a hand-held scanner according to this invention;

Fig 3 is a diagrammatic front view illustrating the internal construction of the optical scanner of Fig. 2;

Fig. 4 is a block diagram illustrating the electronic construction of the optical sensor;

Fig 5 is a flow chart illustrating a procedure for detecting the contacting and proper positioning of the optical scanner with respect to the record medium being scanned;

Fig. 6 is a flow chart of the general mode of operation;

Figs. 7 A and 7B illustrate plan and side views, respectively, of a Braille display in accordance with the invention;

Fig. 8 is an enlarged view of a single pin in an active Braille display; and

Fig. 9 is a flow chart illustrating the mode of operation of translation into

Braille readable form.

Referring now to Fig. 1, there is shown a reading aid for the blind in the form of a scanner 10 held between the thumb 12 and fingers 14 of a hand, with flat tip 16 of the scanner 10 contacting a record medium 18. The fingers 14 are positioned over the Braille display 20. Referring to Figs. 2 and 3, the optical scanner 10 comprises a hand-held pencil shaped housing 22 having an ON/OFF key switch 24, a light source 26 for projecting a beam of light onto the field of view of the record medium (RM) 18, such as a printed text, scanned by a scanner head 28. An optical sensor 30 senses characters printed on the record medium (RM) 18 as scanned by the scanner head 28 and converts them into electrical signals via electronic circuitry 32. This circuitry 32 includes a storage device for storing a converting table, a data processor for processing the electrical signals from the optical sensor 30, for recognizing letters and outputting them in Braille readable form on display 20. The scanner 10 is powered by its own self-contained battery power supply 34 (Fig. 3).

The optical sensor 30 is comprised of a plurality of optical sensing elements arranged in a matrix array as exemplified below with a single CCD array for 64X64 pixels having the size of about 8X8 mm.

Basic Operating procedure;

At least two separate procedures are used by the scanner:

(1 ) A character recognition procedure for detecting the character scanned by the scanner head. This procedure uses conventional pattern recognition such as correlation, curve cooperator etc.

(2) A record medium detector procedure, for detecting the proper positioning of the scanner head in contact with the record medium (RM).

A valid medium positioning is the condition for displaying the scanned characters. This procedure is outlined in more detail further on with reference to Fig. 5. All the procedures use the same optical elements of the scanner: a light source 26 for projecting a beam of light onto the field of view of the record medium (RM) 18 as it scanned by the scanner head 28. The light beam 36 is reflected from the record medium (RM) 18 back into the housing 22 and is focused by lens 38 onto the CCD array optical sensor 30. In order to prevent interference from visible light externally of the housing, light source 26 is preferably a red LED.

Referring to Fig. 4, this is a block diagram illustrating the overall electronic circuitry 32 in the above-described optical scanner 10. The electronic system includes a digital signal processor 40 which receives inputs from the CCD optical sensor 30 after conversion to digital form by an A D converter 42.

Processor 40 includes a CPU 44, which controls the light source 26 used for illumination of the record media 18. The light source 18 is energized at intervals in order to eliminate light interference from external light sources. The light received by the CCD array output from light source 26 is also used to detect the contact between the scanner head 28 and the record media (RM) 18.

Processor 40 also includes a ROM storage device 46 for storing the operational program. It further includes a RAM storage device 48 for use during the normal operation of the electronic translator. The processor 40 also includes inputs from the control key 34 illustrated in Fig 2. A buzzer 50 is used for feedback to the user in case of ON/OFF change mode or other error situations. Fig 5 is a flow chart illustrating how the data processor 40 may be programmed to assure proper ambient light conditions and also proper positioning of the scanner head 28 in contact with the record medium (RM) 18, before processing the output of the optical sensor. Thus, the data processor is programmed to first measure the output of the optical sensor 30 to determine whether the output is below a first predetermined threshold corresponding to acceptable stray light conditions (blocks 60-62). If the sensor output is above that threshold, this indicates that the scanner head may be pointed to a light source, a lit window, or the like accounting for excessive light received by the sensor.

If the sensor output is below the first predetermined threshold, the data processor then checks to determine whether the output is above second predetermined threshold (blocks 64-86); If so, this indicates that the record medium is in proper contact with the scanner head (block 69), and therefore the data processor is enabled to process the character and position data outputted by the sensor (block 70).

Fig 5 includes further optional step that may be performed in case the record medium is black and the data is white (rather than the usual opposite), in which case the output of the decision blocks 68 would be negative even when proper contact is made with the record medium. To anticipate this possibility, a check is made to determine the light level changes between contact and not contact to the record media.

When the scanner head 28 is not in contact with a record medium 18, light source 26 may be pulses at a lower rate (e.g., 30 Hz). When contact with the record medium is detected as described above, the light source 26 may be energized at the higher frequency e.g. 500Hz. This way some energy saving can be made. The optical scanner 10 may be operated such that the data processing is automatically initiated when the scanner head 28 is on the record medium

18.

In the case of scanning two or more lines the scanner will output the characters that are near to the center of the field of view of the scanner.

Fig.6 is a flow chart of the general mode of operation of a Braille readable optical scanner.

Braille "display"

The Braille "display" is a dot matrix display of pins 52 with connector 54 as shown in Figs. 7 A and 7B, that can be raised or lowered. Similar display already exist e.g. Braille series of Sighted Electronics, Northvale, NJ, USA, or DMD 120060 dot matrix display of Metec, Stuttgart, Germany.

The moving mechanism is based on mostly of piezoelectric or electromagnetic mechanism as shown in Fig. 8 illustrating an enlarged single pin 52 and its mechanism 56. Pin 52 is made of stainless steel. In addition, is always tensioned toward the outside of the Braille display by the spring 58. Stopper 60 on the pin 52 prevents the pin from escaping through the aperture 64 in the display envelope 62. A coil 66 is used to generate a magnetic field that pushes or pulls the pin 52. The display outputs the scanned character in a Braille alphabet. A color display may be encoded in various ways. Preferably, lightness is encoded as the range of vertical motion of the pins and hue is encoded as pin motion frequency.

If the scanned information is not recognized the display is translated into corresponding pattern of raised and lower pins.

The essence of the innovation of the present invention is to scan data from the surface of a record medium (RM) and display this data as output on the surface of an active Braille readable display. This display surface is referred to herein as the "upper" surface, because it is positioned on the side of the seamier and away from the scanner head which contacts the RM when in use; but the scope of the invention includes placement of the display area on any surface of the scanner. Line Aligning Feedback

The present invention allows a user to obtain direct feedback, on the Braille display, relating to the changes he or she makes as the scanner head moved on the RM. The user can get feedback on the positioning and orientation of the printed line according to the Braille letters positioning and orientation on the Braille "display"(see Fig.9). If the line of text 92 is at the lower end of the scanner head 94 the letter in the Braille "display" 96 will be at the lower end of the Braille "display" and vice versa. If the scanner head 94 is not parallel 98, 98' to the scanned information, the Braille letters row orientation 100, 100' will reflect the same orientation. This give the user an intuitive feedback of the scanner position regarding the reading line. Various Information Display

One challenge in the translation of a visual display to the Braille output is that the density of the information that can perceived visually is greater then the density of information that can be perceived on the Braille display. This is not a problem in representation of text, which is easily translated to Braille. This is also not a serious problem in the translation of a monochrome display, because one color, for example the dimmer of the two colors, can be represented by pin-up position and the other color, for example the brighter of the two colors, can be represented by a pin-down position. The true challenge is in the rendering of a color display. The colors of color displays have three attributes (hue, lightness and saturation) and it is difficult to encode all three in the Braille output. The approach used to translate a monochrome display can be applied to color displays with strong lightness contrasts but cannot be used generally. The preferred approach of the present invention is to encode hue to frequency of up-and-down motion of the pins, preferably in the range of between 3 Hz - 5Hz, which is adequate for the encoding of four hues, while encoding lightness a . the range of motion of the pins and ignoring saturation. Of course, the choice of which attribute is displayed and which is ignored can be placed under user control, so that, for example, a user may choose to encode saturation as frequency and ignore hue.

It also will be appreciated that the geometric correspondence between the Braille display and the RM may be varied to suit different applications. In particular, the size of the portion of the RM reproduced in display area. The simplest correspondence between the screen display and the Braille display is on pixel per pin but other correspondences are with in the scope of the present invention. For example, resolution may be increased by having more then one pin correspond to one pixel, and resolution may decrease by having more than one pixel correspond to one pin. In addition, the aspect ratio of the display area need not to be the same aspect ratio of the RM. So, for example, one pin may correspond to one pixel interval horizontally and two pixel intervals vertically.

While the invention has been described with respect to several preferred embodiments, it will be appreciated that these are set forth merely for proposes of example, and that many other variations, modifications and applications of the invention may be made.

Claims

1. A compact hand-held portable reading aid for the blind that receives data in electronic form and outputs said data in Braille readable form, comprising:

A rigid hand-held portable elongated housing that can be held with one hand between the thumb and fingers like a pencil, said housing having a top end and a bottom end, means for receiving data in electronic form, a data processor for processing received data and translating it into Braille signals, and an active Braille display on the housing responsive to the Braille signals.

2. A reading aid as in Claim 1, comprising an optical scanner including: a scanner head for scanning a record media; illuminating means for illuminating record media; an optical sensor for sensing information on the record medium; focusing lens for focusing light reflected from the record medium to the optical sensor and for producing an output corresponding thereto; an active Braille display; and a data processor for processing the output of the optical sensor and translating this into Braille readable form; the data processor being programmed to first measure the output of the optical sensor when the scanner head is out of contact with the record medium to assure the output is below a first predetermined threshold, and then to measure the output of the optical seamier when the scanner head is in contact with the record medium to assure that the output is above a second predetermined threshold, before it processes the output of the optical sensor.

3. A reading aid for the blind as in Claim 1, including a cellular telephone that can receive electronic mail and facsimile transmissions and means for converting said transmissions into Braille readable form.

4. A reading aid for the blind as in Claims 1-3, wherein the active Braille display is positioned with respect of the housing to enable direct contact with the fingers used to read Braille when holding the reading aid in a hand.

5. A reading aid for the blind as in Claims 1-4, wherein the active Braille display is on a side of the housing.

6. A reading aid for the blind as in Claim 4, wherein the active Braille display is positioned with respect of the housing to enable direct contact with a forefinger.