WO2021253035A1 - Secure testing device with liquid crystal shutter - Google Patents

Abstract

Device for remote testing, augmented reality or other visualization needs includes a frame configured to be situated on a person's head, a display on the frame, and a combiner assembly supported by and at a front of the frame and configured to allow light transmission therethrough from an environment in front of the combiner assembly and reflection of content from the display being directed to the combiner assembly through airspace between the display and the combiner assembly. The combiner assembly includes an inwardmost, reflective layer separated from the display by airspace and receives and reflects content of the display into the airspace, a second layer that controls transmission of light through the combiner assembly from the environment in front of the combiner assembly, and a third layer covering the second layer and configured to detect tampering with the third layer in order to access the second layer.

Description

SECURE TESTING DEVICE WITH LIQUID CRYSTAL SHUTTER TECHNICAL FIELD

The present invention relates generally to the field of a computer-based system and method for taking a test while ensuring that the test-taker is not receiving assistance from another person or otherwise cheating while taking the test, and that a device used for displaying or taking the test has not been breached and is not being breached or otherwise compromised. A "test" is any type of question-based application that requires analysis by a person taking the test and a response from this person. A test may therefore be considered an examination, a quiz, an assessment, an evaluation, a trial and/or an analysis.

BACKGROUND ART

U.S. Pat. No. 10,359,647 (Vasiliev et al.) and U.S. Pat. Appln. Publ. No. 20200050023 (Vasiliev et al.) assigned to iGlass Technology, Inc. utilize electrochromic technology to control transmission of light from the environment to the eyes of the wearer for the purpose, among others, of preventing an observer other than the wearer from observing the contents of the display. No provision is made for preventing the observer from physically removing a portion of the electrochromic layer to provide a window through the electrochromic layer thus exposing access to a projected display if present and allowing placement of a camera, for example, that can observe the display contents and supply that information to a consultant assisting the student in taking the test.

DISCLOSURE OF INVENTION

The present invention is directed at addressing and ideally solving the problem of guaranteeing with high certainty that a student taking a test is acting alone without the aid of a consultant or other helper or otherwise cheating.

A device in accordance with the invention includes a frame configured to be situated on a person’s head, a display on the frame, and a combiner assembly supported by and at a front of the frame and configured to allow light transmission therethrough from an environment in front of the combiner assembly and reflection of content from the display being directed to the combiner assembly through airspace between the display and the combiner assembly. There is thus a combination of light being provided through the combiner assembly, that of the environment in front of the device and that of the display being reflected by the combiner assembly. As a result, the person can view the environment in front of the device and the content of the display, both at the same time or at different times dependent on the state of operation of the combiner assembly, and more specifically, a component thereof.

The combiner assembly includes a first layer on a side toward a rear of the frame, a second layer outward of the first layer and a third layer outward of the second layer such that the second layer is between the first and third layers. The first layer is a reflective layer separated from the display by airspace and receives and reflects content of the display into the airspace when the frame is on the person’ s head. The second layer controls transmission of light through the combiner assembly from the environment in front of the combiner assembly. The third layer covers the second layer and detects tampering with the third layer in order to access the second layer. The second layer is an electrochromic layer or a liquid crystal light control layer. Also, the second layer has a first state wherein all light is prevented from passing through the combiner assembly to thereby provide a blocking state to the combiner assembly and a second state wherein only a portion of light is prevented from passing through the combiner assembly. The second layer is controllable to selectively provide the first state or the second state. The first, second and third layers may be coextensive. Preferably, the first layer is in contact with the second layer and the second layer is in contact with the third layer. The third layer preferably covers the second layer.

A processor in the frame controls content of the display. The processor may be coupled, e.g., by wires, to the second layer to control light transmission provided by the second layer and to the third layer to detect tampering with the third layer in order to access the second layer and to affect functionality of the device when tampering is detected. One or more cameras on the frame obtains images of one or both eyes of the person when the frame is on the person’s head, and the obtained images are used for biometric identification purposes and/or to monitor viewing by the person when the frame is on the person’s head.

The third layer includes a thin clear plastic film, a thin metal trace on the film, and a pair of pads that terminate the metal trace. The processor on the frame connects to the pair of pads and monitors the trace to detect variation in an electrical characteristic of the trace indicative of tampering with the third layer.

There may be a housing on the frame, and the processor may be in the housing. The combiner assembly can extend downward from the housing and the display is in the housing above the combiner assembly.

Another embodiment of the device has a multi-layered structure of the combiner assembly as a preferred embodiment and includes a frame, a display on the frame, and the combiner assembly. At least one camera is provided on a part of the frame and operatively obtains images of one or both eyes of the person. The obtained images are used for biometric identification purposes and or to monitor viewing by the person when the frame is on the person’s head. The same variants described in the preceding embodiment may be present in this embodiment as well.

BRIEF DESCRIPTION OF DRAWINGS

The following drawings are illustrative of embodiments of the system developed or adapted using the teachings of at least one of the embodiments disclosed herein and are not meant to limit the scope of the disclosure as encompassed by the claims.

FIG. 1 illustrates a combiner assembly with a CID and blocking film.

FIG. 2 is an exploded view of the combiner assembly shown in FIG. 1.

FIG. 3 illustrates a flex circuit connector cable passing through CID joint to connect to a circuit on a printed circuit board. FIG. 4 illustrates the use of light from a display to illuminate an iris of a person wearing the device.

BEST MODE FOR PRACTICING THE INVENTION

FIG. 1 illustrates an inventive monitor 10 using a combiner or combiner assembly 12. Monitor 10 comprises a frame 14 adapted to be supported by a user’s head as shown in FIG. 4, and a housing 16 on the frame 14 at a front of the frame 14. The frame 14 may include a band that extends from one side of the housing 16 to the opposite side 14 and is configured to encircle the head of the user.

Combiner assembly 12 has lateral edges spaced apart from respective lateral sides of the frame of the device to form gaps 18 between the combiner assembly 12 and housing 16 alongside the eyes of the person when the frame 14 is on the person’s head, one gap 18 on each side of the monitor 10. These gaps 18 can be closed to prevent viewing of the combiner assembly 12 from the side or bottom.

As shown in FIG. 2, the combiner assembly 12 includes at least three layers, i.e., it has a multi-layered or multi-film construction, which may be the same for both or different. In this manner, it is an assembly of three different layers that may be coextensive with one another, with the intermediate layer being in contact with the adjacent layers.

An inner or inwardmost layer 20 is a reflective lens which reflects light from one or more display(s) 22 in the housing 16 to the eyes of the test-taker, also referred to as a display assembly. Each display 22 displays content as determined by a processor 66 in the housing 16 (shown in dotted lines as a substrate or printed circuit board in FIG. 1). Each display 22 is spaced apart from the combiner assembly 12 so that the content as light rays is transmitted through airspace 24 between the inner layer 20 and the housing 16, see FIG. 4. The reflective lens, i.e., inner layer 20, reflects the content, often images, from the display 22 to be viewed by the person wearing the monitor 10 so that the person views the combiner assembly 12 and sees the content of the display 22. The person can see through the combiner assembly 12 at the same time, i.e., simultaneously, that the reflective lens is partly reflecting the content onto the combiner assembly 12. There can be one display of each eye.

Intermediate layer 26 of the combiner assembly 12 is an electrochromic or liquid crystal light control layer which controls transmission of light through the combiner assembly 12. This can be called a blocking film. In the case of the liquid crystal implementation, the amount of light allowed to pass through the layer 26 can vary from near 0% to about 98%. When it is electrically set between the extremes of this range, the wearer, whether a test-taker or otherwise, can see the environment in front of the monitor 10 through the combiner assembly 12, which is useful for augmented reality applications, and also at the same time and through the same combiner assembly 12, the reflected content from the display 22. However, anyone standing in front of the wearer can also see what is displayed on the combiner assembly 12 and thus the test questions when the wearer is in a test-taking mode. The writing will be reversed so the observer will need a mirror to be able to read the text or it can be captured by a camera and processed by a computer. For the test-taking mode, therefore, the transmissivity of the intermediate layer 26 can be set to near 0% blocking the transmission of the test questions through the combiner assembly 12.

The liquid crystal implementation of the blocking film is commonly used in glasses designed for viewing 3D TV. In this case, the right and left lenses, also referred to as display portions of the combiner assembly 12, are alternately turned into blocking and non-blocking modes synchronized with a signal emitted from a specially designed TV. The electrochromic implementation is described in U.S. Pat. No. 10,359,647 (Vasiliev).

If access to the blocking film, intermediate layer 26, is accessible, a portion of the blocking film can be removed opening a window in the blocking film for the placement of a camera, for example, to capture test questions. To eliminate this possibility, the blocking film is covered with a chassis intrusion detector (CID) 28, as an outer or outwardmost layer of the three-layered combiner assembly 12 (although an optional cover layer may be provided over the combiner assembly 12).

CID 28 comprises a thin clear plastic film upon which is placed a thin metal trace. The metal trace can be about 0.002 inches wide on about 0.010 inch centers. About 80% of the film is not covered by the metal traces allowing for light to pass through. The thickness of the metal trace can be about 5 microns to about 25 microns. The trace can begin and end each at a pad each about 0.010 inch in diameter which can have metal on both sides of the film allowing for connections to the electronic circuits for the case where the CID 28 covers such circuits. There are many metals that can be used, such as Indian tin oxide.

A private key, or the code for generating such a key, for decoding test questions and any other commands sent by the test-providing institution is held in volatile RAM memory in, for example, housing 16. This can be kept alive through an extended life (10 years) battery which also can be recharged when monitor 10 is connected to a power supply (not shown). If CID 28 detects an attempt to break into combiner assembly 12, then power to the RAM memory is shut off and the private key and any other private information or algorithms erased. Other techniques to disable the operability of the monitor 10 for a test as a result of the detected attempt to break into the combiner assembly 12 and/or housing 16 are also possible, either alternative to or additional to the erasure of the private key.

The blocking film, i.e., intermediate layer 26, and CID 28 can be connected to the electronics printed circuit board (PCB) which constitutes or supports the processor 66 on the frame 14, and typically in the housing 16, which is done by, for example, wires shown generally at 30 and 32. Wires 30, 32 used can be in the form of flex circuits as will be discussed below. This processor 66 in the housing 16 controls content of the display 22, and can direct the blocking film to block the combiner assembly 12 or more generally control light transmission provided by the blocking film of the combiner assembly 12. The same processor 66 could also detect attempts to access the blocking film and affect functionality of the combiner assembly 12 or monitor 10 when an attempt to access the blocking film is detected. One or two cameras, not shown, can be used to monitor the blocking film to make sure that it has not been disabled. When blocking is on, for example during test-taking, the blocking film, i.e., intermediate layer 26, should be opaque. This can be seen by camera(s) placed above or alongside of the display(s) 22 facing the combiner assembly 12. The display 22 can momentarily display a coded image which can then been seen by the camera(s) and a comparison made. If the test fails, the display 22 can be turned off.

As shown, combiner assembly 12 comprises two (right and left) combiner portions 34, 36 attached to and descending from the housing 16, one associated with each eye of the person on whose head the monitor 10 is supported. Combiner portions 34, 36 may be integral with and horizontally alongside one another. A monitor 10 with only one combiner portion 34 or 36 for only one eye of the person may also be constructed.

This illustrated embodiment is not intended to limit the invention and a combiner assembly 12 with one curved portion that covers both eyes is also part of the invention. Such a combiner assembly 12 would have a first lateral edge outward of the right eye and its other lateral edge outward of the left eye to thereby transverse the entire face of the user and be positioned in front of both eyes of the user. Thus, the combiner assembly 12 is supported by the frame 14 in a position at least partly in front of at least one eye of the person (and preferably both eyes) when the frame 14 is on the person’s head and configured to allow simultaneous viewing by the person of an environment in front of the person through the combiner assembly 12 and content on the display 22 being directed to the inner, face facing surface of the combiner assembly 12 through the airspace 24 between the display 22 and the combiner assembly 12 and reflected by the combiner assembly 12 to one or both eyes. Thus, the two part combiner assembly, one part for each eye, is not critical to the invention and a single combiner assembly spanning both eyes is possible.

FIG. 4 shows another optional feature, namely, a camera 38 situated at the bottom of the combiner assembly 12, e.g., mounted on a support structure 40 of or coupled to the housing 16 that extends between combiner portions 34, 36 and has a bottom section below the combiner portions 34, 36. The support 40 with camera 38 mounted thereon may be eliminated and instead, one or more such cameras 38 may be provided on the housing 16, and possibly the frame 14, to image one or both eyes of the person when the monitor 10 is on their head, with the images being used for biometric identification purposes and/or to monitor the viewing direction of the person. Thus, the support 40 is not critical to the invention.

In one embodiment, the lowest edge of the part of the frame 14 or housing 16 thereof on which the camera 38 is situated, or the lowest edge of the combiner assembly 12 if there is no part of the monitor 10 underneath it, is not intended to be against the wearer’s face when the frame is worn, as are virtual reality headsets which seek to block all ambient light (which is clearly seen in FIG. 4). Rather, there is a space below and on the sides of combiner assembly 12 and the wearer’s face to provide monitor 10 with an open configuration (as opposed to the closed configuration of virtual reality headsets). There is airspace 24 between the combiner assembly 12 and the person’s face 42 and eyes 44 through which the content of the display 22 is projected (see the dotted lines in FIG. 4). However, this space may be closed as in virtual reality headsets, and is presence or absence is not critical to the invention.

The blocking film, i.e., intermediate layer 26, can also be extended beyond the combiner assembly 12 to block visual access to other paths where light from the display(s) 22 could leak.

The liquid crystal version of the blocking film, i.e., intermediate layer 26, can be switched in a small fraction of a second and thus by controlling the ratio of on-to-off time, it can be used to dim the light coming from the environment as a sort of sunglasses. An ambient light sensor can be added to control the amount of dimming. Combiner assembly 12 is therefore able to allow viewing of the environment in front of the monitor through its three-layered structure 20, 26, 28 while also allowing view of the content being reflected by the reflective lens, i.e., inner layer 20, from the display(s) 22.

FIG. 3 illustrates the manner in which a printed circuit board (PCB) 62 is protected by a chassis intrusion detector (CID) system 68, which PCB 62 may be in the housing 16 and have the processor 66 thereon. A flex ribbon circuit, e.g., from the combiner assembly 12, is illustrated passing through a CID joint generally at 46 in FIG. 3. Ribbon 48 of this flex circuit 46 is about 10 mm wide, about 130 microns thick with, for example, about 18 -micron thick by about 1 mm wide conductors 50 sandwiched between two layers of plastic with appropriate adhesive layers. Ribbons 48 of the flex circuit 46 can be bonded using adhesive 52 to the CID layers 54 of the CID 68, i.e., thin plastic film containing the metal trace. The conductors terminate at solder pads 56. During assembly, the flex circuit 46 is placed over pins 58, 60 in or on the PCB 62 where the solder pads 56 on the flex circuit 46 line up with solder pads on PCB 62 (not shown). Heat is then applied with an air gun or hot bar, for example, and the solder pads 56 melt and attach to each other making the appropriate connections to the printed circuit board 62. After all the flex circuits 46 are attached to the PCB 62, the edges of the CID layers 54 are bonded together and to flex circuits 46. When the process is completed, it will not be possible to penetrate the CID 68 in an effort to access the processor 66 without breaking one or more conductors 50 in the CID 68, which results in a variation in an electrical characteristic of the wires detectable by the processor 66 on PCB 62, which then erases the contents of the RAM. Access to and tampering with the processor 66 is thereby prevented.

Using liquid crystal technology, the view through the combiner assembly 12 can be blocked adding to the security of the secure test-taking apparatus and method. In this case, the liquid crystal blocking film, i.e., intermediate layer 26, can be turned totally black or opaque by a control mechanism so that the contents of the display 22 cannot be seen from a person standing in front of the test-taker.

Various methods can be used with the monitor 10 to permit the test- taker to enter commands to the monitor 10. One such method using the iris camera is track the motion of the eye which is usable to select answers to the questions or to control the operation of the monitor. Eye blinking and time or duration of closing also can be used for this purpose. Another such method is to use gestures which can be seen by a forward-facing camera 64 in the housing 16 and interpreted by appropriate software executed by processor 66. Teeth clicking, for example, can be used for controlling the test and for choosing various of the multiple choices for a test question. Also, and more likely, a conventional user interface such as a mouse, keyboard or voice-detecting speaker, may be used to control the monitor 10 as disclosed in other patent publications of the assignee.

Method for taking tests and administering tests using the monitor 10 described above are also considered to be part of the invention. Methods for ensuring a test-taker is not cheating also considered to be part of the invention. Although the monitor 10 described herein is for particular use for test-taking, they are not limited to such use and other uses for the monitor 10, e.g., gaming, are also considered as being part of the invention.

Although several preferred embodiments are illustrated and described above, there are possible combinations using other geometries, sensors, materials and different dimensions for the components that perform the same functions. At least one of the inventions disclosed herein is not limited to the above embodiments and should be determined by the following claims. There are also numerous additional applications in addition to those described above. Many changes, modifications, variations and other uses and applications of the subject invention will, however, become apparent to those skilled in the art after considering this specification and the accompanying drawings which disclose the preferred embodiments thereof. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the following claims.

Claims

1. A device (10), comprising : a frame (14) configured to be situated on a person’s head; a display (22) on said frame (14); and a combiner assembly (12) supported by and at a front of said frame (14) and configured to allow light transmission therethrough from an environment in front of said combiner assembly (12) and reflection of content from said display (22) being directed to said combiner assembly (12) through airspace between said display (22) and said combiner assembly (12); said combiner assembly (12) comprising a first layer (20) on a side toward a rear of said frame (16), a second layer (26) outward of said first layer (20) and a third layer (28) outward of said second layer (26) such that said second layer (26) is between said first and third layers (20, 28), said first layer (20) being a reflective layer separated from said display (22) by airspace (24) and receiving and reflecting content of said display (22) into the airspace (24) when said frame (16) is on the person’ s head; said second layer (26) controlling transmission of light through said combiner assembly (12) from the environment in front of said combiner assembly (12); and said third layer (28) covering said second layer (26) and being configured to detect tampering with said third layer (28) in order to access said second layer (26).

2. The device (10) of claim 1, wherein said second layer (26) is an electrochromic layer.

3. The device (10) of claim 1, wherein said second layer (26) is a liquid crystal light control layer.

4. The device (10) of claim 3, wherein said second layer (26) has a first state wherein all light is prevent from passing through said combiner assembly (12) to thereby provide a blocking state to said combiner assembly (12) and a second state wherein only a portion of light is prevented from passing through said combiner assembly (12), said second layer (26) being controllable to selectively provide the first state or the second state.

5. The device (10) of claim 1, further comprising: a processor (66) on said frame (14) that controls content of said display (22)1 and a chassis intrusion detector system (68) around said processor (66) and configured to detect tampering with said chassis intrusion detector system (68) in order to access said processor (66).

6. The device (10) of claim 1, further comprising a processor (66) on said frame (14) and which is coupled to said second layer (26) to control light transmission provided by said second layer (26) and to said third layer (28) to detect tampering with said third layer (28) in order to access said second layer (26) and to affect functionality of the device (10) when tampering is detected.

7. The device (10) of claim 6, further comprising wires (32, 34) to connect said second and third layers (26, 28) to said processor (66).

8. The device (10) of claim 1, further comprising a camera (38) on said frame (16) and configured to obtain images of one or both eyes (44) of the person when said frame (16) is on the person’ s head, whereby obtained images are used for biometric identification purposes or to monitor viewing by the person when said frame (16) is on the person’s head.

9. The device (10) of claim 1, wherein said first, second and third layers (20, 26, 28) are coextensive.

10. The device (10) of claim 1, wherein said third layer (28) comprises a thin clear plastic film (48), a thin metal trace (50) on said film (48), and a pair of pads (56) that terminate said metal trace (50).

11. The device (10) of claim 10, further comprising a processor (66) on said frame (14) connected to said pair of pads (56) and monitoring said trace (50) to detect variation in an electrical characteristic of said trace (50) indicative of tampering with said third layer (28).

12. The device (10) of claim 1, further comprising: a housing (16) on said frame (14); and a processor in said housing (16) and which is coupled to said second layer (26) to control light transmission provided by said second layer (26) and to said third layer (28) to detect tampering with said third layer (28) in order to access said second layer (26) and to affect functionality of the device (10) when tampering is detected.

13. The device (10) of claim 12, wherein said combiner assembly (12) extends downward from said housing (16) and said display (22) is in said housing (16) above said combiner assembly (12).

14. The device (10) of claim 1, wherein said first layer (20) is in contact with said second layer (26) and said second layer (26) is in contact with said third layer (28).

15. The device (10) of claim 1, wherein said third layer (28) covers said second layer

(26).