Proximity sensor for determining two-dimensional coordinates of a proximal object

• US 9,164,625 B2
• Filed: 06/24/2014
• Issued: 10/20/2015
• Est. Priority Date: 10/14/2012
• Status: Active Grant

• Current Assignee: Neonode, Inc.
• Original Assignee: Neonode, Inc.
• Inventors: Holmgren, Stefan, Iyer, Sairam, Berglind, Richard, Nordstrm, Karl Erik Patrik, Sparf, Lars, Rosengren, Per, Rosengren, Erik, Karlsson, John, Eriksson, Thomas, Jubner, Alexander, Behdasht, Remo, Fellin, Simon, Shain, Joseph, Aman, Robin Kjell
• Primary Examiner(s): MYHR, JUSTIN L
• Application Number:
  US14/312,787
• Publication Number:
  US 20140364218A1
• Time in Patent Office: 483 Days
• Field of Search: 345156-179, 715/786
• US Class Current: 1/1
• CPC Class Codes: A63F 13/21 characterised by their sensors, purposes or types
• CPC Class Codes: A63F 13/211 using inertial sensors, e.g. accelerometers or gyroscopes
• CPC Class Codes: A63F 13/213 comprising photodetecting means, e.g. cameras, photodiodes or infrared cells A63F13/219, A63F13/655 take precedence
• CPC Class Codes: A63F 13/26 having at least one additional display device, e.g. on the game controller or outside a game booth
• CPC Class Codes: A63F 13/31 Communication aspects specific to video games, e.g. between several handheld game devices at close range
• CPC Class Codes: A63F 13/33 using wide area network [WAN] connections
• CPC Class Codes: A63F 13/355 Performing operations on behalf of clients with restricted processing capabilities, e.g. servers transform changing game scene into an encoded video stream for transmitting to a mobile phone or a thin client
• CPC Class Codes: A63F 13/428 involving motion or position input signals, e.g. signals representing the rotation of an input controller or a player's arm motions sensed by accelerometers or gyroscopes
• CPC Class Codes: A63F 13/92 Video game devices specially adapted to be hand-held while playing
• CPC Class Codes: A63F 2009/245 visual
• CPC Class Codes: A63F 9/24 Electric games; Games using electronic circuits not otherwise provided for video games A63F13/00; computerized gaming systems G07F17/32
• CPC Class Codes: G01J 1/0411 using focussing or collimating elements, i.e. lenses or mirrors; Aberration correction
• CPC Class Codes: G01J 1/42 using electric radiation detectors optical or mechanical part G01J1/04; by comparison with a reference light or electric value G01J1/10
• CPC Class Codes: G01S 17/04 Systems determining the presence of a target
• CPC Class Codes: G01S 17/48 Active triangulation systems, i.e. using the transmission and reflection of electromagnetic waves other than radio waves
• CPC Class Codes: G01S 17/88 Lidar systems specially adapted for specific applications
• CPC Class Codes: G01S 7/4811 common to transmitter and receiver
• CPC Class Codes: G01S 7/4813 Housing arrangements
• CPC Class Codes: G01S 7/4815 using multiple transmitters
• CPC Class Codes: G06F 1/1616 with folding flat displays, e.g. laptop computers or notebooks having a clamshell configuration, with body parts pivoting to an open position around an axis parallel to the plane they define in closed position
• CPC Class Codes: G06F 1/169 : the I/O peripheral being an integrated pointing device, e.g. trackball in the palm rest area, mini-joystick integrated between keyboard keys, touch pads or touch stripes G06F1/1643 takes precedence; constructional details of pointing devices G06F3/033
• CPC Class Codes: G06F 2203/04809 : Textured surface identifying touch areas, e.g. overlay structure for a virtual keyboard
• CPC Class Codes: G06F 3/017 : Gesture based interaction, e.g. based on a set of recognized hand gestures interaction based on gestures traced on a digitiser G06F3/04883
• CPC Class Codes: G06F 3/021 : Arrangements integrating additional peripherals in a keyboard, e.g. card or barcode reader, optical scanner
• CPC Class Codes: G06F 3/0219 : Special purpose keyboards
• CPC Class Codes: G06F 3/0304 : Detection arrangements using opto-electronic means constructional details of pointing devices not related to the detection arrangement using opto-electronic means G06F3/033; optical digitisers G06F3/042
• CPC Class Codes: G06F 3/03547 : Touch pads, in which fingers can move on a surface
• CPC Class Codes: G06F 3/0421 : by interrupting or reflecting a light beam, e.g. optical touch-screen
• CPC Class Codes: G06F 3/0428 : by sensing at the edges of the touch surface the interruption of optical paths, e.g. an illumination plane, parallel to the touch surface which may be virtual sensing beam interruptions in a planar beam grid of an optical touch-screen G06F3/0421
• CPC Class Codes: G06F 3/0488 : using a touch-screen or digitiser, e.g. input of commands through traced gestures
• CPC Class Codes: G06F 3/04883 : for inputting data by handwriting, e.g. gesture or text

Abstract

A proximity sensor including a housing, a plurality of light pulse emitters for projecting light out of the housing along a detection plane, a plurality of primary light detectors for detecting reflections of the light projected by the emitters, by a reflective object in the detection plane, a plurality of primary lenses oriented relative to the emitters and primary detectors in such a manner that for each emitter-detector pair, light emitted by the emitter of that pair passes through one of the primary lenses and is reflected by the object back through one of the primary lenses to the detector of that pair when the object is located at a position, from among a primary set of positions in the detection plane, that position being associated with that emitter-detector pair, and a processor for co-activating emitter-detector pairs, and configured to calculate a location of the object in the detection plane.

Claims

1. A proximity sensor for determining two-dimensional coordinates of a proximal object, comprising:

a housing;

a plurality of light pulse emitters mounted in said housing for projecting light out of said housing along a detection plane;

a plurality of primary light detectors mounted in said housing for detecting reflections of the light projected by said emitters, by a reflective object in the detection plane;

a plurality of primary lenses mounted and oriented in said housing relative to said emitters and said primary detectors in such a manner that for each emitter-detector pair, light emitted by the emitter of that pair passes through one of the primary lenses and is reflected by the object back through one of the primary lenses to the detector of that pair when the object is located at a two-dimensional position, from among a primary set of positions in the detection plane, that position being associated with that emitter-detector pair; and

a processor connected to said emitters and to said primary detectors, for synchronously co-activating emitter-detector pairs, and configured to calculate a two-dimensional location of the object in the detection plane by;

determining an emitter-detector pair among the co-activated emitter-detector pairs, for which the detector detects a maximum amount of light, and identifying the position associated therewith,

determining additional positions that are associated with co-activated emitter-detector pairs and that neighbor the thus-identified position, and

calculating a weighted average of the thus-identified position and the thus-determined additional positions, wherein each position'"'"'s weight in the average corresponds to a degree of detection of the reflected light beam for the emitter-detector pair to which that position is associated.

2. The proximity sensor of claim 1, wherein said processor is configured to calculate the location of the object in the detection plane using the Hough transform by:

providing a plurality of candidate ellipses within the detection plane,

determining co-activated emitter-detector pairs for which the detector generates a detection signal, and identifying the positions associated therewith,

interpolating the detection signals for any two of the co-activated emitter-detector pairs whose two associated positions are neighbors, to determine an intermediate location between those two associated positions,

assigning an orientation to each intermediate location, the orientation being perpendicular to the line connecting the two neighboring associated positions,

for each candidate ellipse;

assigning a match value to the candidate ellipsis, the match value representing a degree of match between an edge of the candidate ellipsis and the location and orientation of an intermediate location, and

calculating a sum of the thus-assigned match values, and

designating that candidate ellipse with the maximum thus-calculated sum as being the location of the object in the detection plane.

3. The proximity sensor of claim 1, wherein said processor further infers that the object is moving in a direction parallel to an optical axis of one of said primary lenses when the emitter of the thus-determined emitter-detector pair continues to be the same emitter over a time series of object location calculations, and the amount of light detected by the detector of that pair has the same ratio to the amount of light detected by the detector of a co-activated pair, with which one of the additional positions is associated, over the time series of calculations.

4. The proximity sensor of claim 1, wherein said lenses are oriented so that for each emitter-detector pair, when the object is located at the associated position in the detection plane, the light emitted by the emitter of the pair is reflected by the object back to the detector at an angle θ

or −

θ

with respect to an optical axis of one of said primary lenses, and wherein said processor further infers that the object is moving in a direction parallel to that angle θ

or −

θ

with respect to the optical axis when the detector of the thus-determined emitter-detector pair continues to be the same detector over a time series of object location calculations, and the amount of light detected by the detector of that pair has the same ratio to the amount of light detected by the detector of a co-activated pair, with which one of the additional positions is associated, over the time series of calculations.

5. The proximity sensor of claim 1, wherein the co-activated emitter-detector pairs include:

at least one emitter-detector pair for which the emitter is the same emitter as in the thus-determined emitter-detector pair, and

at least one emitter-detector pair for which the detector is the same detector as in the thus-determined emitter-detector pair.

6. The proximity sensor of claim 1, further comprising a plurality of secondary light detectors mounted in said housing for detecting reflections of the projected light by a reflective object in the detection plane, such that for each emitter-detector pair of an emitter with a secondary detector, light emitted by the emitter of the pair passes through one of said primary lenses and is reflected by the object back through one of said primary lenses to the detector of the pair when the object is located at a two-dimensional position, from among a secondary set of positions in the detection plane, the secondary set of positions being different than the primary set of positions.

7. The proximity sensor of claim 6 wherein neighboring ones of the secondary set of positions are closer together than neighboring ones of the primary set of positions.

8. The proximity sensor of claim 1, further comprising:

a plurality of secondary light detectors mounted in said housing for detecting reflections of the projected light by a reflective object in the detection plane; and

a plurality of secondary lenses mounted and oriented in said housing relative to said emitters and said secondary detectors in such a manner that for each emitter-detector pair of an emitter with a secondary detector, light emitted by the emitter of that pair passes through one of said primary lenses and is reflected by the object through one of the secondary lenses back to the detector of that pair when the object is located at a two-dimensional position, from among a secondary set of positions in the detection plane, the secondary set of positions being different than the primary set of positions.

9. The proximity sensor of claim 8 wherein neighboring ones of the secondary set of positions are closer together than neighboring ones of the primary set of positions.

10. The proximity sensor of claim 1, wherein the detection plane passes over a reflective surface, and wherein said primary lenses direct the light beams projected by said emitters at an upward angle relative to said reflective surface, to minimize reflections of the projected light by the surface.

11. The proximity sensor of claim 1, wherein said emitters and primary detectors comprise diodes that are mounted in said housing without individual plastic casing lenses and without individual substrates.

12. A plurality of proximity sensors for determining three-dimensional coordinates of a proximal object, comprising a plurality of the proximity sensors of claim 1 directed toward respective, intersecting detection planes.

13. The plurality of proximity sensors of claim 12, wherein each proximity sensor is aimed in a direction substantially perpendicular to the direction in which another of the proximity sensors is aimed.