EYE CONTROLLED OPTO-ELECTRIC INPUT/OUTPUT INTERFACE

Abstract: An eye controlled opto-electric input/output interface comprising: a collimating and reflecting optical arrangement (9); a picture presentation device (6) arranged at one of the focal planes of the optical arrangement (9); a partly light permeable beam splitter (8) placed between the picture presentation device (6) and the optical arrangement (9), such that a reflecting surface of said beam splitter (8) intersects the optical axis of the optical arrangement (9); and a light sensitive organ (13, 14) intersecting the optical axis of the optical arrangement (9) on the side of the optical arrangement (9) facing the picture presentation device (6) and being arranged to record light passing the optical arrangement (9).

Description: EYE CONTROLLED OPTO-ELECTRIC INPUT/OUTPUT INTERFACE Field of the Invention The present invention relates to an eye controlled optoelectric input/output interface. Background of the Invention In certain apparatuses there is a requirement for eye controlled input of information signals or control signals. In certain applications the requirement is due to a user's need to utilize the control resource of the eyes, in some cases in order to free other organs for other tasks and in other cases because of a handicap. In other applications the requirement is due to the apparatus to be controlled. In the area of i.a. computers and telecommunication, miniaturization has been carried far and increased the usability of such devices. However, an obstacle to further increased usability and miniaturization is now found in input devices that take up a great deal of space. For example, a useful keyboard is much larger than the components needed for information processing or information communication. Examples of prior art dealing with eye control are found in the European patent publications EP-0 270 636 and EP-0 500 672, which are hereby incorporated by reference. These publications relate to apparatuses for detection of the gaze direction of a persons eye and eye controlled input/output interfaces that are applicable to e.g. communication devices, computers and cameras. A picture is presented to the eye via a lens and mirror system, and by detecting the gaze direction it can be determined what part of the picture the eye is watching. In communication apparatuses and computers, the pictures can e.g. be command menus or characters, and input to the apparatus is carried out by choosing the command or the character to be input. In cameras, eye control of the focussing adjustment is used in such a way that focus is automatically set for the area of the picture on which the gaze is directed. In the above mentioned examples, the eye is presented with a picture which in different realizations may be a projection of a real object or a picture shown on a display or monitor. The eye perceives a virtual picture as if it was located at a certain distance from the eye on an optical axis going through the focal point of the eye. These applications require a detection of a picture of the eye by means of some kind of photodetector, e.g. a CCD-matrix or a video camera, concurrently with the eye's registration of the presented picture. This eye picture detector should in most applications be located outside the visual field of the eye, which in accordance with prior art is achieved by means of a system of lenses and mirrors such that the picture of the eye is projected on the eye picture detector at the same time as another picture is presented to the eye itself. In order to focus both the picture presented to the eye on the focal plane of the eye. i.e. the retina, and the picture of the eye on the focal plane of the photodetector. certain distances are required between picture source, lenses, eye and photodetector. A drawback in such apparatuses according to prior art is that the distance requirements entail incon- venientiy large arrangements. Another drawback is the fact that these known apparatuses are not adapted to general input or output of information, for example image information. Object of the Invention The problem to be solved by the present invention is to provide an eye controlled input/output interface for inputting and/or outputting information to and/or from an information handling apparatus. An aspect of the problem is to provide a general input/output interface for inputting control commands as well as text and image information. The problem is solved according to the invention with an apparatus in accordance with the independent claims. The invention will now be described with the aid of exemplifying embodiments in conjunction with the enclosed drawings. Brief Description of the Drawings It is shown in: Fig 1 a general view of an optical component comprised in embodiments of the invention; Fig 2 a general view of a second embodiment of the optical component according to fig 1: Fig 3 a general view of an embodiment of an eye controlled input/output interface according to the invention; Fig 4 a general view of the beam path in an embodiment of the invention according to fig 3; Fig 5 A, 5B and 6 a general view of a further embodiment of an eye controlled input/output interface according to the invention; and in Fig 7-11 different embodiments of the invention. Description of Embodiments The possibility to achieve an interface according to the invention of acceptable size is highly dependent on the design of the optical system. The figures 1-4 show an optical component 9 having light refractive as well as light reflective properties, which advantageously can be comprised in different embodiments of the invention. Fig 1 shows a first embodiment of an optical device 9, in which a positive, collimating lens 10 is arranged to co-operate with a reflecting member 12, herein also called a reflector. The lens 10 is preferably composed of two or more sublenses. and is arranged to accomplish a parallel light beam from diverging light falling into the lens and coming from a light source 6 located in one of the foci 5 or focal planes 30 of the lens. The reflector 12 is in fig 1 placed at a distance A from the surface of the lens 10 that is turned away from the light source. The optical device 9 may also comprise distance organs 7, generally shown in fig 1, arranged to keep the reflector on the distance A from the lens 10. The reflector 12 has a reflective surface 32 having the same bending curve as the surface of the lens that is turned away from the light source. A light beam, coming from the light source and falling into the lens, is refracted in the lens a first time and is then reflected back into the lens by the reflector 12. Fig 2 shows a second embodiment of the optical device 9, in which the reflector 12 is applied in immediate contact with the surface of the lens 10 that is turned away from the light source. This is particularly advantageous since the reflective surface of the reflector follows the surface of the lens and thereby the curve of the reflector can be suited to the lens with precision. The reflector can for example be made of or comprise metalic or dielectric materials, and can be applied to the surface of the lens for example by a vaporizing procedure. It is for certain applications suitable that the reflector is devised to be partly permeable, and thus transmits a certain amount of the light falling into the lens while the remaining part of the light is reflected back into the lens. The reflector may also be devised such that it is permeable for one or more selected and predetermined light wavelengths, while other light wavelengths are reflected back into the lens. For example, the reflector may be permeable for light in the infrared wavelength range and reflecting for other wavelengths. The reflector may also be impermeable for all light. The optical device 9 according to the invention is for the sake of simplicity hereinafter also called reflector lens. The above described reflector lens 9 is useful in different apparatuses that require a collimating device, particularly in such applications that require small dimensions and/or low weight. Fig 3 shows the invention incorporated in a apparatus 2 for detection of the gaze direction of an eye, more exactly in an eye controlled input/output device 2 e.g. for communication apparatuses, computers and cameras. A light source 6, for example in the shape of an LCD-display or an objective lens comprising a focussing screen on which an image is projected, is located in the focal plane of a reflector lens 9 as described above. A partly transparent beam splitter 8, here in the shape of a mirror, is arranged between the light source 6 and the reflector lens 9. A light sensitive device 13,14, comprising an image recording device 14 e.g. in the shape of a CCD, a vidicon tube or an emulsion based film (e.g. silver halide) and possible a lens or an objective 13 for focussing an image on an image plane of the image recording device, is arranged behind the reflector lens 9 seen from the light source 6. The apparatus 2 according to fig 3 comprises an optional member 3 for collecting light reflected by the beam splitter 8. The member 3 is absent in some embodiments of the apparatus 2, but may in other embodiments be another light sensitive device similar to the device 13,14 or a finder in the shape of an aperture with or without a light refractive lens. In those cases that the light source 6, the image recording device 14 and/or the member 3 are electrically controllable or can produce an electric output signal, said devices are provided with inputs and/or outputs for electric signals. In one embodiment of the apparatus 2. a picture is presented on the light source 6 which is situated in the focal plane of the reflector lens 9. Light beams from the picture goes through the beam splitter 8 and are collimatingly refracted in the reflector lens 9, whereupon at least a part of the light quantity first is re-reflected through the reflector lens 9 and is then reflected by the beam splitter 8 towards an aperture 3. A user's eye gazing through the aperture 3 sees the picture reflected from the beam splitter 8 and concurrently an image of the eye is reflected by the beam splitter 8 towards the light sensitive device 13.14. The gaze direction of the eye can be determined in a manner known e.g. through the above mentioned prior art documents and thereby can also the part of the picture being gazed at be determined. The beam path in a device according to fig 3 is generally shown in fig 4. A diverging light beam, having its origin in a point of the light source situated on the optical axis of the reflector lens 9 and being drawn with fully drawn lines, goes through the beam splitter 8 and falls into the reflector lens 9. The light beam is collimated by the light refractive part 10 of the reflector lens 9. The diverging light beam is then reflected by the reflecting organ 12 of the reflector lens 9 back through the light refractive part 10. The light being reflected into the reflector lens 9 goes out from the lens in collimated form, i.e. as a parallel light beam, and is again reflected by the beam splitter 8 towards an eye 1 drawn in fig 4. Light from another point of the light source is collimated and reflected in an analogue manner, an example of which is drawn with intermittent lines. Parallel light is thus falling on the eye and the eye perceives a presented picture as if it was situated at a larger distance from the eye. Fig 5A, 5B, 6, 7A, 7B and 8 shows an eye controlled input/output interface 2, in addition to the above mentioned components further comprising an objective for projection of an object image on an image plane. It is clear from fig 5B and 7B, respectively, that different embodiments of the reflector lens can be used. It is also possible to use a per se known optical system. In these embodiments, the object image is projected on the same image recording device 14 as the one which is used for the detection of an image of an eye. According to fig 5 A and 6, the image recording device 14 is pivotable around an axis 16, such that the organ 14 can be switched between recording of an image of an eye (fig 5 A) and recording of an image projected through the objective 18, i.e. used as a camera. The embodiment according to fig 7 comprises a mirror 20 that is pivotable around an axis 22, such that either an image of an eye (fig 7 A) or an image of another object can be projected on the image recording device 14. In the camera setting of these embodiments, i.e. when the interface is set to record an image through the objective 18, it is advantageous to output the recorded image on a picture presentation device 6 e.g. in the shape of an LCD-display in order to present the picture to the eye. The interface will then operate as a camera with a finder, and the user can by means of a trigger 36 (fig 5 A, 7 A) grab an image for storage or for transmission through telecommunication. Fig 9 shows in perspective an embodiment of the inventive interface 2, in which the picture presentation device 6 and the image recording device 13,14 are placed in mutually perpendicular first and second planes. The beam splitter 8 is arranged such that it reflects light in a direction having an axis perpendicularly intersecting a third plane, which in its turn is perpendicular to the first and second planes. An objective 18 is placed in a fourth plane being parallel to the third plane. The interface 2 further comprises a mirror 24 being pivotably arranged on an axis 38. In a first position (as in fig 9) an image of an eye is reflected into the image recording device 14. In a second position, when the mirror 24 is turned 90 degrees around the axis 38, an image from the objective is instead reflected into the image recording device 14. As for the rest, the same functions as described above are found in this embodiment of the interface 2. Fig 10 shows in a side view the mirror 24 that is suspended on an axis 38, and fig 11 shows the relative position of the members 6, 14, 18 in relation to the gaze direction of a users eye 1. Fig 12 shows the use of an interface 2 communicatively coupled to a telecommunication device 40 and/or an information processing apparatus 42. The objective 18 reproduces an object 39. Reference numerals A distance 1 eye 2 eye controlled input/output interface 3 light catching member, e.g. an aperture or a detector 5 focus 6 light source, picture presentation device 7 distance organ 8 beam splitter 9 optical arrangement, reflector lens 10 lens 12 reflecting device 13 lens, objective 14 image recording device 15 inputs/outputs for electric signals 16 axis 18 objective 20 mirror 22 axis 24 mirror 30 focal plane 32 reflective surface 36 trigger 38 axis 39 object 40 telecommunication apparatus 42 information processing apparatus

Claims: Claims 1. An eye controlled opto-electric input/output interface comprising: - a collimating and reflecting optical arrangement (9); - a picture presentation device (6) arranged at one of the focal planes of the optical arrangement (9); - a partly light permeable beam splitter (8) placed between the picture presentation device (6) and the optical arrangement (9) such that a reflecting surface of said beam splitter (8) intersects the optical axis of the optical arrangement (9). 2. The eye controlled interface according to claim 1 , further comprising an objective for projecting an object on an image recording device (14). 3. The eye controlled interface according to any of the preceding claims, further comprising organs (16,20,22,24,38) for selectively exposing the image recording device (14) to light from the optical arrangement (9) or the objective (18). 4. The eye controlled interface according to any of the preceding claims, further comprising a mirror (20,24) being pivotable around an axis (22,38) for selectively reflect- ing light from the optical arrangement (9) or from the objective (18) on the image recording device (14). 5. The eye controlled interface according to any of the preceding claims, being arranged such that an image recorded by the image recording device (14) is presentable on the picture presentation device (6). 6. The eye controlled interface according to any of the preceding claims, being communicatively coupled to a telecommunication device (40) and/or to an information processing device apparatus (42) for storing and/or transmitting control commands, text information or image information. 7. An optical apparatus (9) comprising: - a positive lens (10) being devised to produce a parallel light beam from a diverging light beam falling into said lens and originating from a light source located in a focus of said lens; - a light reflecting device (12) being located on the side of the lens that is turned away from the light source and having a reflective surface with the same bending curve as the surface of the lens that is turned away from the light source. 8. The optical apparatus (9) according to claim 7. wherein the light reflecting device (12) is permeable for a certain amount of light falling through the lens. 9. The optical apparatus (9) according to any of the preceding claims, wherein the light reflecting device (12) is permeable for a predetermined wavelength. 10. The optical apparatus (9) according to any of the preceding claims, wherein the light reflecting device (12) is arranged at a distance (A) from the surface of the lens (10). 11. The optical apparatus (9) according to any of the preceding claims, comprising a distance device (7) for arranging the light reflecting device (12) at said distance (A) from the surface of the lens (10). 12. The optical apparatus (9) according to any of the preceding claims, wherein the light reflecting device (12) is applied in contact with the surface of the lens (10). 13. The optical apparatus (9) according to any of the preceding claims, wherein the light reflecting device (12) is vaporized to the surface of the lens (10). 14. The optical apparatus (9) according to any of the preceding claims, wherein the light reflecting device (12) comprises a metallic material. 15. The optical apparatus (9) according to any of the preceding claims, wherein the light reflecting device (12) comprises a dielectric material. 16. A collimating device comprising: - a reflector lens in the shape of an optical apparatus (9) according to any of the claims 1-9; - a picture presentation device (6) arranged at one of the focal planes of the reflector lens (9); - a partly light permeable beam splitter (8) placed between the picture presentation device (6) and the optical apparatus (9), such that a reflecting surface of said beam splitter (8) intersects the optical axis of the reflector lens (9). 17. An opto-electric input/output interface comprising: - a reflector lens in the shape of an optical apparatus (9) according to any of the claims 1-9; - a picture presentation device (6) arranged at one of the focal planes of the reflector lens (9); - a partly light permeable beam splitter (8) placed between the picture presentation device (6) and the optical apparatus (9), such that a reflecting surface of said beam splitter (8) intersects the optical axis of the reflector lens (9); - a light sensitive device (13,14) located such that it intersects the optical axis of the reflector lens (9) on the side of the reflector lens (9) opposite the picture presentation device (6) and being devised to detect light passing through the reflector lens (9). 18. The opto-electric input/output interface according to claim 11, wherein the light sensitive device is arranged to record light being reflected into the reflector lens (9) by the beam splitter (8).

Inventors: ERICSSON JONAS, ERICSSON, JONAS
Applicants: ECT AB EYE CONTROL TECH, ERICSSON JONAS, ECT AB EYE CONTROL TECHNIQUE, ERICSSON, JONAS
Application year: 1998
Main classification: G06F3
IPC codes: G06F3