IE85833B1

IE85833B1 - A viewing device

Info

Publication number: IE85833B1
Application number: IE2006/0517A
Authority: IE
Inventors: Alan Johnston Francis
Original assignee: Ash Technologies Research Limited
Filing date: 2006-07-14
Publication date: 2011-08-17

Abstract

ABSTRACT This invention relates to a viewing device. In particular this invention relates to a viewing device suitable for use by the partially sighted or visually impaired to assist in viewing of a surface, such as a page of reading material. This invention is aimed at providing an improved viewing device which overcomes at least some of the disadvantages of conventional viewing devices.

Description

Introduction This invention relates to a viewing device. In particular this invention relates to a viewing device suitable for use by the partially sighted or visually impaired to assist in viewing of a surface, such as a page of reading material.

This invention is aimed at providing an improved viewing device which overcomes at least some of the disadvantages of conventional viewing devices.

Statements of Invention According to the invention there is provided a handheld. optical device according to claim I.

The magniﬁcation varying means may comprise a mechanical means.

Ideally the capturing means is movable relative to the housing in a direction substantially parallel to a plane of a surface to be viewed. The handheld optical device of the invention is particularly compact. By arranging the capturing means to move in a direction parallel to the plane of the surface being viewed, the overall size of the device is minimised. The housing may have a bme surface, and the capturing means may be movable relative to the housing in a direction substantially parallel to a plane of the base surface.

In another case the capturing means is conﬁgured to face in a direction substantially parallel to a plane of a surface to be viewed. By arranging the capturing means to face in a direction parallel to the plane of the surface being viewed, the overall size of the device is minimised. The housing may have a base surface, and the capturing means may face in .. a direction substantially parallel to a plane of the base surface. The device may comprise a mirror to deflect a visual image from a surface to be viewed to the capturing means.

The direction in which the capturing means faces may be the direction of a line from the centre of a light sensitive array of the capturing means and normal to the plane of the light sensitive array. Typically the light sensitive array is an electronic charge-coupied- device or CMOS sensor.

In another embodiment the magniﬁcation varying means is coupled to the capturing means by a rack-and-pinion arrangement. Preferably the capturing means comprises a toothed rail axially movable relative to the housing. The toothed rail may be movable in a direction parallel to the direction in which the capturing means faces. Ideally the magnification varying means comprises a co-operating toothed cog rotatable relative to the housing. The magniﬁcation varying means may comprise a ﬁnger control operable to move the capturing means relative to the housing. The ﬁnger control is a particularly easy-to-use, ergonomic means of varying the magnification. In particular, the user may operate the ﬁnger control using a single ﬁnger only. Preferably the ﬁnger control comprises a ﬁnger wheel coupled to the cog. Ideally at least part of the ﬁnger wheel is accessible ﬁ'om externally of the housing. The ﬁnger control may comprise a scroll wheel. Most preferably housing encloses at least part of the magnification varying means. The housing may enclose the capturing means.

In one case the magnification varying means is rotatable to" vary the magniﬁcation of a visual image captured. The magniﬁcation varying means may be rotatable about an axis substantially parallel to a plane of a base surface of the housing. The magniﬁcation varying means may be rotatable about an axis substantially perpendicular to the direction in which the capturing means faces.

The device may focus on surfaces at different distances from the housing. This arrangement enables the device to focus on a sheet of paper which the housing is being moved across, for example as a user reads text on the sheet of paper. This arrangement (Al (Al also enables the device to be lifted away from the sheet of paper to provide the user with an overview of what part of the sheet of paper the text being read is.

Ideally in the focusing conﬁguration wherein the focussing means is conﬁgured to maintain a visual image captured in focus, upon varying of the magniﬁcation of the visual image captured. Most preferably in the ﬁrst focussing conﬁguration the focussing means is movable relative to the housing. In the first focussing conﬁguration the focussing means may be movable relative to the capturing means. Preferably in the ﬁrst focussing conﬁguration the ratio of the distance between the capturing means and the focussing means to the distance between the focussing means and a surface to be viewed is proportional to the magnification required.

Ideally in the first focussing conﬁguration the housing is conﬁgured to be located against a surface to be viewed.

In one case in the second focussing conﬁguration the capturing means is ﬁxed relative to the housing. Preferably the second focussing conﬁguration the focussing means is ﬁxed relative to the housing. Ideally in the second focussing conﬁguration the focussing means is fixed relative to the capturing means. Most preferably in the second focussing conﬁguration the housing is conﬁgured to be located spaced-apart from a surface to be viewed.

The focussing means may comprise a lens. in another embodiment the device comprises means to support t:he housing at a location spaced-apart from a surface to be viewed. When the housing is supported spaced-apart from the surface, this enables a user to write on the stnface being viewed. Preferably the support means is mounted to the housing. Ideally the support means is movable between a supporting conﬁguration and a stowed conﬁguration.

The capturing means may comprise a camera.

Brief Description of the Drawingg The invention will be more clearly understood from ﬂae following description of an embodiment thereof, given by way of example only, with reference to the accompanying drawings, in which: - Fig. 1 is a perspective view of a viewing device according to the invention in an open display conﬁguration; Fig. 2 is a perspective View of the device of Fig. 1 in a closed storage conﬁguration; Fig. 3 is an exploded, perspective view of a base housing part of the device of Fig. 1; Fig. 4 is an exploded, perspective view of a top housing part of the device of Fig. 1; Fig. 5 is a perspective view of a capturing means of the device of Fig. 1; Fig. 6 is a perspective view of a part of the capturing means of Fig. 5; Figs. 7 and 8 are exploded, perspective views of die capturing means of Fig.

; Fig. 8(a) is an exploded, perspective view of a part of the capturing means of Fig. 5; Fig. 8(b) is a perspective view of the capturing means of Fig. 5; Fig. 8(c) is an end view of the capturing means of Fig. 5; and Figs. 9 and 10 are perspective views of the device of Fig. 1, in use.

Detailed Description Referring to the drawings, there is illustrated a viewing device 1 according to the invention. The device 1 comprises a display unit 2 and a handheld optical device 3.

The optical device 3 is connected to the display unit 2 by means of a flexible lead 26 (Fig. 10).

The device 1 has a ﬁrst capturing conﬁguration in which the optical device 3 is ﬁxed relative to the display unit 2 (Fig. 1) and a second capturing conﬁguration in which the optical device 3 is movable relative to the display unit 2 (Fig. 10).

The optical device 3 is suitable for location in proximity to a surface to be viewed, such as a page of reading material. The device 3 may be placed resting against the page, or may be placed above the page in certain circumstances. The device 3 comprises a handheld housing 4, a camera 40 enclosed within the housing 4 for capturingavisual irnageofatleastpartofasurface,suchasapageofreading material, a focussing lens 5 for focussing the visual image captured, and a mechanical means for varying the magniﬁcation of a visual image captured.

The camera 40 faces in a direction parallel to the plane of a base surface 14 of the housing 4. Typically the base surface 14 of the housing 4 is placed against the surface to be viewed, such as a page of reading material. Thus the camera 40 faces in a direction parallel to the plane of the page of reading material to be viewed. A mirror 15 is mounted within the housing 4 inclined at approximately 45° to the plane of the base surface 14 (Fig. 7). The mirror 15 deﬂects the visual image from the page of reading material to the camera 40.

The optical device 3 has a first focussing conﬁguration for focussing a captured visual image of the page of reading material when the housing 4 is located resting against the page of reading material, and a second focussing conﬁguration for focussing a captured visual image of the page of reading material when the housing 4 is spaced—apart from the page of reading material, for example held approximately 10cm (4") above the page of reading material.

The mechanical means is provided, in this case, in the form of a ﬁnger scroll wheel 6 and two large toothed cogs 7, 8 (Fig. 7). The large cogs 7, 8 are rotatably mounted to the housing 4. The ﬁnger wheel 6 has a small toothed cog 9, 10 at each side of the wheel 6, and the finger wheel 6 is coupled to the large cogs 7, 8 by means of engagement between the small cogs 9, l0 and the large cogs 7, 8 (Fig. 6).

The camera 40 and the lens 5 are mounted to a camera frame 11 (Fig. 8). Two toothed rails 12, 13 extend axially from the frame 11 (Fig. 8). The large cogs 7, 8 are coupled to the frame 11 by means of engagement between the large cogs 7’, 8 and the rails 12, 13 (Fig. 7).

In this manner, the mechanical means is coupled to the camera 40 by a rack-and-c pinion arrangement.

In the first focussing conﬁguration the ﬁnger wheel 6 is operated by rotating the wheel 6 about the axis A-A which passes through the small cogs 9, 10 (Fig. 7). The axis A-A is substantially parallel to the plane of the base surface 14 of the housing 4.

Operation of the ﬁnger wheel 6 causes the camera frame 11, the camera 40 and the lens 5 to move axially relative to the housing 4, and thus relative to the mirror 15 to vary the magniﬁcation of a visual image captured. The camera 40 and the lens 5 move in a direction parallel to the plane of the base surface 14 of the housing 4.

Typically the base surface 14 of the housing 4 is placed against the surface to be viewed, such as a page of reading material. Thus the camera 40 and the lens 5 move in a direction parallel to the plane of the page of reading material to be viewed.

In the ﬁrst focussing conﬁguration, as the lens 5 moves relative to the housing 4, the lens 5 also moves relative to the camera 40. The lens 5 is arranged to ensure that the ratio of the distance between the camera 40 and the lens 5 to the distance between the lms 5 and the page of reading material is proportional to the magniﬁcation required. In this manner the lens 5 maintains the captured visual image in focus, upon varying of the magniﬁcation of the captured visual image.

' In further detail, U is the distance from the paper to the lens 5; V is the distance from the lens 5 to the sensor 40, M is the magniﬁcation and F is the focal length of the lens 5. The device 3 is arranged such that M=U/V assuming that the lens 5 is placed appropriately to focus the image, and llF=lIU + 1/V.

Referring to Fig. 8(a), in the ﬁrst focussing conﬁguration the camera system 40 is focussed on the plane of the camera base 14, generally the document being read. As the camera assembly 11 slide forwards and backwards on the guide rails 41, the cam followers on the lens holder 5 track the cam in the guide rails 41 causing the lens holder 5 to rotate. ‘The screw thread on the lens holder 5 and its counterpart in the camera chassis 11 cause the lens 5 to approach and recede from the camera sensor 40 adjusting the focus in such a way that focus is maintained on the base 14 of the camera 4, for example the document , at all positions of the camera system. By this means the optical magniﬁcation of the camera system is altered.

. It is of beneﬁt to the operator of this magnifying device to be able to obtain an overview of the document they are reading in order to position themselves within the page. This is achieved using the second focussing conﬁguration. To accomplish this, the camera assembly 11 is moved back further by the user rotating the scroll wheel 6. The rear stop feature 43 on the camera holder 44 comes into contact with the rear stop feature 45 on the guide rails 41 forcing the camera holder 44 to move forward relative to the lens holder 5. This causes the focal plane to move ﬁmher away from the base 14 of the camaa 4. The distances are chosen so that when the clip 46 engages in the détente 47, the focal plane is approximately 10 cms beyond the base 14 of the camera module 4, allowing the user to raise the camera module 4 above the document and still maintain a substantial degree of focus.

The overview mode is also suitable for using writing stands 50. ' a In the second focussing conﬁguration the camera 40 remains ﬁxed relative to the housing 4, the lens 5 remains ﬁxed relative to the housing 4, and the camera 40 remains fixed relative to the lens 5.

When the user rotates the scroll wheel 6 forwards, the camera ‘assembly 44 exits from the détente hold position and is returned to the ﬁrst focussing conﬁguration operating position by the leaf spring features 48 bearing on the camera holder 44.

The small cogs 9, 10, the large cogs 7, 8, the camera frame 11, and the toothed rails 12, 13 are all enclosed within the housing 4. Part of the ﬁnger wheel 6 protrudes out of the housing 4 and is thus accessible from externally of the housing 4 (Fig. 5).

The optical device 3 also comprises two support stands 50 mounted to the base surface 14 of the housing 4 (Figs. 8(b) and 8(c)). Each stand 50 is movable relative to the housing 4 between a supporting conﬁguration and a stowed conﬁguration. In the supporting conﬁguration the stands 50 support the housing 4 at a location spaced- apart ii-om the page of reading material.

The support means 50 are provided to support at least part of the optical device 3 above a surface to be viewed, such as a page of reading material. The support means 50 may be provided in the form of one or more legs. The legs 50 may be arranged to move between a stowed conﬁguration and an extended configuration. In one case the legs 50 ﬂip out when required to support the optical device 3 above the page.

By supporting at least part of the optical device 3 above the page, this enables the user to write on the page and simultaneously view what is being written on the display 25. In this manner the ﬂip-out legs 50 may support the optical device 3 in a writing conﬁguration.

The display unit 2 comprises a housing 20 having a base part 21 and a top part 22.

In the ﬁrst capturing conﬁguration, the optical device 3 is mounted to the base part 21 (Fig. 1), and in the second capturing conﬁguration the optical device 3 is demounted from the base part 21 (Fig. 10).

Thebasepart2l has anopening23 inabase surface 24ofthebasepart21. Inthe first capturing conﬁguration, the base surface 14 of the optical device 3 is flush with the base surface 24 of the base part 2] . Typically in the first capturing conﬁguration, the base part 21 is placed resting upon a surface to be viewed, such as a page of reading material. Because the base part 21 and the optical device 3 are ﬂush,_the optical device 3 also rests upon the page. The optical device 3 then captures a visual image of a surface, such as a page of reading material, through the opening 23.

Mounted to the top part 22 is a flat —screen electronic display 25 to display a visual image captured by the optical device 3.

The top part 22 is attached to the base part 21 by means of a hinge arrangement to facilitate movement of the top part 22 relative to the base part 21 between a closed storage conﬁguration (Fig. 2) and an open display conﬁguration (Fig. 1). In the closed storage conﬁguration, the display 25 and the optical device 3 are enclosed within the housing 20.

The base part 21 comprises a reception space 27 for stowing at least part of the lead 26. An access door 28 is openable in a hinging manner to reveal the reception space 27 and closable in a hinging manner for stcwing of the lead 26.

When the access door 28 is closed, the door 28 engages the optical device 3 to releasably attach the optical device 3 to the base part 21 in the first capturing conﬁguration. To release theoptical device 3, the door 28' may be opened.

In the second capturing configuration, the optical device 3 is located in the proximity of a surface to be viewed. For example the optical device 3 may be placed resting upon a surface to be viewed, such as a page of reading material. The display unit 2 may or may not be placed against the page.

In use, the top part 22 is moved relative to the base part 21 from the closed storage conﬁguration (Fig. 2) to the open display conﬁguration (Fig. 1). In the first capturing conﬁguration with the optical device 3 mounted to the base part 2], the basepart21 is placed restingagainstasurfacetobeviewed,suchasapage of reading material. Because the optical device 3 is ﬂush with the base part 21, the optical device 3 also rests against the page.

The optical device 3 captures a visual image of the page through the opening 23 in the base part 21, and the captured visual image is displayed on the display 25 for the user to view. The magnification of the visual image may be varied by the user by rotating the ﬁnger wheel 6 using a ﬁnger.

If appropriate the user may move the base part 21 and the optical device 3 across the page by sliding the base part 21 over the page. Because the optical device 3 is mounted to the base part 21 in the first capturing conﬁguration, the base part 21 and the optical device 3 move together over the page.

The viewing device 1 of the invention also accommodates movement of the optical device 3 relative to the base part 21 in the second capturing conﬁguration.

To arrange the viewing device 1 in the second capturing conﬁguration, the access door 28 is hinged open (Fig. 9) and a length of the stowed lead 26 is removed from the reception space 27. The optical device 3 is then demounted from the base part 21, and the optical device 3 is placed resting against the page (Fig. I0).

If appropriate the user may move the optical device 3 across the page by sliding the optical device 3 over the page while maintaining the position of the base part 21 ﬁxed.

In further detail, Fig. 1 illustrates the lid 22 opened. The device 1 can be used with the mouse camera 3 in the docking station 21. Fig. 2 illustrates the device I in the stored position with the lid 22 closed. Figs. 3 and 4 illustrate the exploded assembly 21, 22. Fig. 5 illustrates the mouse assembly 3 complete. Fig. 6 illustrates the mouse assembly 3 with the top cover 4, the button and the printed circuit board removed. Fig. 7 illustrates the mouse assembly 3 partially exploded. Fig. 8 illustrates the mouse assembly 3 ﬁilly exploded. Fig. 8(b) illustrates the underside of the camera module 4 showing one writing stand 50 extended. Fig. 8(c) illustrates an end view of the camera module 4 with one writing stand 50 extended. Fig. 9 illustrates the cable door 28 lifted to reveal the mouse cable 26. The mouse 3 can now be removed. Fig. 10 illustrates the mouse 3 removed from the docking station for remote use.

The invention is not limited to the embodiment hereinbefore described, with reference to the accompanying drawings, which may be varied in construction and detail.

Claims

1. Claims A handheld optical device for location in proximity to a surface to be viewed, the device comprising:- a handheld housing; means to capture avisual image ofat least part ofthe surface; ~ ~ means for varying the magniﬁcation of a visual image captured, the magniﬁcation varying means being operable to move the capturing means relative to the housing to vary the magniﬁcation of a visual image captured; and meansto focusavisualimage captured, thedevicehaving aﬁrstfocussing conﬁguration for focussing a visual image captured of at least part of a surface located at a first distance from the housing, and a second focussing conﬁguration for focussing a visual image captured of at least part of a surface located at a second distance from the housing. A device as claimed in claim I wherein the magniﬁcation varying means comprises a mechanical means. A device as claimed in claim I or 2 wherein the capturing means is movable relative to the housing in a direction substantially parallel to a plane of a surface to be viewed. Adeviceasclaimedinanyofclaimslto3whereinthehousinghasabase surface, and the capturing means is movable relative to the housing in a direction substantially parallel to a plane of the base surface. A device asclaimedinanyofclaims I to4whereinthecap11n-ingmeansis conﬁgured to face in a direction substantially parallel to a plane of a surface to be viewed. Adevice asclaimedinanyofclaims 1 to Swlmeinthe houslnghasabase surface, and the capturing means faces in a direction substantially parallel to a plane of the base surface. Adeviceasclaimedinanyofclaims 1 to6whereinthedevicecomprisesa mirrortodeﬂectavisual imageﬁomasurfacetobeviewedtothecapturing means. A device as claimed in any of claims 2 to 7 wherein the magniﬁcation varying means is coupled to the capturing means by a rack-and-pinion arrangement. A device as claimed in claim 8 wherein the capturing means comprises a toothed rail axially movable relative to the housing. A device as claimed in claim 9 wherein the magniﬁcmion varying means comprises a co—opera1ing toothed cog rotatable relative to the housing. A device as claimed in any of claims 1 to 10 wherein the magniﬁcation varying means comprises a ﬁnger control operable to move the capturing means relative to the housing. A device as claimed in claim 11 wherein the ﬁnger control comprises a finger wheel coupled to the cog. A device as claimed in claim 12 wherein at least part of the ﬁnger wheel is accessible from externally of the housing. Adeviceasclaimedinanyofclairns 11 to Bwhereintlieﬁngercontrol comprises a scroll wheel. A device as claimed in any of claims 1 to 14 wherein the housing encloses at least part of the magniﬁcation varying means. Adeviceaselairnedinanyofclaims 1 to 15 whereinthe housingenclosesthe capturingmeans. A device as claimed in any of claims 2 to 16 wherein the magniﬁcation varying means is rotatable to vary the magniﬁcation of a visual image captured. A device as claimed in claim 17 wherein the magniﬁcation varying means is rotatable about an axis substantially parallel to a plane of a base surface of the housing. Adevice asclaimedinany ofclaims 1 to l8whereinintheﬁrstfocussing_ conﬁguration the focussing means is conﬁgured to maintain a visual image captured in focus, uponvaryingofthemagniﬁcation ofthevisual image captured. A device as claimed in claim l9 wherein in the first focussing conﬁguration the focussing means is movable relative to the housing. A device as claimed in claim 19 or 20 wherein in the first focussing conﬁguration the focussing means is movable relative to the capturing means. Advice as claimedinany ofc1aims19to 21 whereinintheﬁrstfocussing conﬁguration the ratio of the distance between the capturing means and the focussing means to the distance between the focussing means and a surface to be viewed is proportional to the magniﬁcation required. Adevice as claimed inanyofclaims 1 to 22 whereininthe ﬁrstfocussing conﬁguration the housing is conﬁgured to be located against a surface to be viewed. A device as claimed in any of claims I to 23 wherein in the second focussing conﬁguration the capturing means is ﬁxed relative to the housing. A device as claimedinanyofclaims 1 to 24whereininthc secondfocussing conﬁguration the focussing means is ﬁxed relative to the housing. A device as claimed in any of claims 1 to 25 wherein in the second focussing conﬁguration the focussing means is ﬁxed relative to the capturing means. A deviceasclaimedinanyofclaims 1to26whereininthesecondfocnssing conﬁguration the housing is conﬁgured to be located spaced-apart ﬁom a surface to be viewed. A device as claimed in any of claims 1 to 27 wherein the focusing means comprises a lens. A device as claimed in any ofclaims 1 to 28 wherein the device comprises means to support the housing at a location spaced-apart from a surface to be viewed. A device as claimed in claim 29 wherein the support means is mounted to the housing. A device as claimed in claim 29 or 30 support means is movable between a supporting conﬁguration and a stowed conﬁguration. Adeviceasclaimedinanyofclaimsltoﬁ whereinthecaptmingmeans comprises a camera. , A handheld optical device for location in proximity to a surface to be viewed substantially as hereinbefore described with reference to the accompanying drawings.