Patent Document

CROSS-REFERENCES TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 14/158,013, filed Jan. 17, 2014, which is a continuation of U.S. patent application Ser. No. 13/618,910, filed Sep. 14, 2012, now U.S. Pat. No. 8,668,584, issued Mar. 11, 2014, which is a continuation of U.S. patent application Ser. No. 13/077,606, filed Mar. 31, 2011, now U.S. Pat. No. 8,398,488, issued Mar. 19, 2013, which is a continuation of U.S. patent application Ser. No. 10/921,518, filed Aug. 19, 2004, now U.S. Pat. No. 7,942,744, issued May 17, 2011, the entire contents of each of which are incorporated herein by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates to a system for providing a virtual input, such as for an electronic gaming machine. 
       BACKGROUND OF THE INVENTION 
       [0003]    Player interaction with a gaming machine is typically limited to touching a touch screen sensor or depressing an electro-mechanical switch. A touch screen sensor usually fits the shape and size of an associated active display, such as an LCD or a CRT. 
         [0004]    A typical gaming touch screen assembly consists of a touch screen sensor attached to the front surface of an active display device, such as a CRT or an LCD. The sensor is connected to a touch screen controller, which sends touch position data to the game controller. The basic sensor material is typically plastic or glass and requires a transparent conductive oxide (TCO) layer, such as Indium Tin Oxide (ITO), wires or acoustic components to work. The specifics depend on the type of touch screen technology (capacitive, resistive, acoustic and near-field). 
         [0005]    The sensor surfaces are typically flat, but could be slightly curved, such as for example CRT&#39;s. All of these conventional sensor technologies have limitations when dealing with large surface sizes, non-planar or discontinuous surfaces, and no-contact requirements. This limits the areas where a touch screen can be used on a gaming machine, or other systems requiring such user input. 
         [0006]    Additionally, electro-mechanical switches have limitations. Electro-mechanical switches have been used on gaming machines for decades. The number of switches is limited by the size of the mechanical panel. And when the game on the gaming machine is changed, the switches and/or labels must be replaced. Therefore, they are not programmable and must be located in a convenient location for the player to reach. 
         [0007]    A primary objective of this invention is to provide another form of user input, such as for a gaming machine, other than using a conventional physical surface or mechanical device. The present system is able to sense a touch on a virtual surface. The virtual surface may be in the middle of the air. The virtual surface may be close to the actual surface, so close it seems that it was a physical touch. 
       SUMMARY 
       [0008]    This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0009]    The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein: 
           [0010]      FIG. 1  is a block diagram of a virtual input system according to the present invention; 
           [0011]      FIG. 2  is a block diagram of a Doppler radar sensor module as utilized by the virtual input system of  FIG. 1 ; 
           [0012]      FIG. 3  is a block diagram of an ultrasonic sensor module as utilized by the virtual input system of  FIG. 1 ; 
           [0013]      FIGS. 4   a  and  4   b  are respective front and side views of a gaming machine top box which utilizes the virtual input system of  FIG. 1 ; 
           [0014]      FIG. 5  is a view of a hemispherical display of the top box of  FIGS. 4   a  and  4   b;    
           [0015]      FIG. 6  is a block diagram of an IR camera sensor according to the present invention; and 
           [0016]      FIG. 7  is a block diagram of an IR/laser scanning sensor, according to the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    While this invention is susceptible of embodiments in many different forms, there is shown in the drawings and will herein be described in detail, preferred embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspect of the invention to the embodiments illustrated. 
         [0018]    The present invention is described herein with respect to an interactive game surface device (IGSD)  10 , a specific embodiment for use in conjunction with a gaming machine. It should be understood that the present invention is also applicable for use with other systems requiring similar user input. 
         [0019]    The IGSD  10  allows any surface, non-conductive or otherwise, to be used for player input. It allows a player to touch an animated figure or a non-planar display in a top box of a gaming device, discussed below. The IGSD  10  also allows the player to use a hand or body movement as an interactive input. 
         [0020]    In a first embodiment, the IGSD  10  includes a first sensor module, such as a lower power Doppler radar sensor module  12 , and a second sensor module, such as an ultrasonic sensor module  14 . Alternatively, and as discussed further below, the IGSD may include only single Doppler radar sensor module, multiple Doppler radar sensor modules, an IR camera, or an infrared/laser scan sensor. 
         [0021]    According to Doppler radar theory, a constant frequency signal that is reflected off a moving surface, in this case the skin or clothing of the player, will result in a reflected signal at the same frequency, but with a time varying phase indicative of the relative motion. 
         [0022]    In the first embodiment, the Doppler radar sensor module  12  senses movement of all or part of the body via skin or clothing reflections. The Doppler radar sensor module  12  could sense the light movement of the fingers, even the beating of a heart. 
         [0023]    With software mapping, the Doppler radar sensor module  12  can sense net amount of motion, mean speed, and average direction for objects in its field of view. With frequency modulation, the Doppler radar sensor module  12  can sense range. 
         [0024]    The Doppler radar sensor module  12  must be physically located such that it has a view of the player unobstructed by a surface which is opaque to radar, such as a conductive surface. The center of the field of sensing of the Doppler radar sensor module  12  is usually perpendicular to the orientation of its antenna. The Doppler radar sensor module  12  could be mounted at the side of the gaming machine and aimed so that its field of sensing goes across, or on top of, a surface, which could be metal. The field of sensing would be limited, but this might be desirable for a particular application. 
         [0025]    The ultrasonic sensor module  14  utilizes sound energy, or sonar signals, at frequencies of 20 to 100 Kh range. Solid objects reflect this sound energy, and the time difference between transmission and reception indicates range and direction. 
         [0026]    Radar signals and sonar signals have different reflective and speed characteristics. Therefore, they are a good combination when dealing with distances between 2-3 cm to 5 meters. 
         [0027]    The IGSD  10  also includes an IGSD controller  18 , such as a dedicated embedded controller or a standard microprocessor. The IGSD controller  18  provides control, power, interface, and data translation for the Doppler radar and ultrasonic sensor modules  12 ,  14 . The IGSD controller  18  also includes a conventional USB communication channel  20  to a host  24 . 
         [0028]    The Doppler radar sensor module  12  uses a low power (&lt;10 mw) 2.45 Ghz microwave sensor. Referring to  FIG. 2 , the Doppler radar sensor module  12  includes a first micro-patch array  26  as a receiving antenna and a second micro-patch array  28  as a transmitting antenna. 
         [0029]    The radar module  12  can be configured for continuous wave (CW) operation or for frequency modulated/continuous wave (FM-CW) operation. The CW configuration provides simple motion detection only. The FM-CW configuration adds range sensing. 
         [0030]    The Doppler radar sensor module  12  is provided with a 15 to 20 degree beam-width with a range of 20 to 1 feet. Depending on the location of the antennas  26 ,  28  of the Doppler radar sensor module  12  within the gaming machine, not only can the Doppler radar sensor module  12  detect objects at the front of the gaming machine, but also hands and fingers touching the surface of the gaming machine. 
         [0031]    The Doppler radar sensor module  12  can provide motion and range detection. However when the Doppler radar sensor module  12  is used alone, there can be problems with reflections and noise from multiple sources, such as large groups of people or metal carts in the vicinity of the gaming machine. This potential problem can be minimized or prevented by using multiple radar modules  12 , discussed below. However, one can preferably also use ultrasonic sensors on the low side of the electromagnetic frequency spectrum, as also discussed below. 
         [0032]    As illustrated in  FIG. 3 , the ultrasonic sensor module  14  drives several 38-80 kHz ultrasonic transceivers, or sensors,  30 . Each of the ultrasonic sensors  30  includes an ultrasonic transmitter  30   a  and an ultrasonic receiver  30   b . The ultrasonic sensors  30  are small, cylindrical sensors which can be installed in various points on the gaming machine. The sensors  30  connect to the rest of the ultrasonic module  14  via cable. Using data processing, the IGSD controller  18  determines the best data image. 
         [0033]    Although the IGSD controller  18  preferably includes dual ultrasonic sensors, one sensor can be used, or two of the same type of sensor. Other types of sensors could be used if the application requires such, such as an optical sensor. 
         [0034]    Referring to  FIG. 1 , the IGSD controller  18  provides control and data translation. The USB communication interface  20  is provided between the IGSD controller  18  and the host system  24 . The host system  24  provides set-up information, which is used by the IGSD controller  18  and the sensor modules  12 ,  14 . 
         [0035]    The sensor modules  12 ,  14  acquire data in the form of sensor images. After data processing, the modules  12 ,  14  send data streams to the IGSB controller  18 . The IGSD controller  18  processes this data, looking for sequences and combinations that match parameters loaded in during a set-up routine. For example, the host system  24  wants the IGSD  10  to perform two functions: 1) provide a people sensor during an attract mode; and 2) provide touch data during bonus mode. 
         [0036]    The host system  24  continuously provides mode status to the IGSD  10 , which in turn changes the parameters for determining what data, and when data, is sent to the host system  24 . 
         [0037]    Each of the sensor modules  12 ,  14 , includes a respective processor  12   a ,  14   a . The present system was designed to maximize the workload of the processors  12   a ,  14   a , on each respective sensor module  12 ,  14 , allowing the IGSD controller  18  to handle the integration of both data images from the modules  12 ,  14 . This could be a function of the host system  24  if the processor of the host system  24  could handle the extra workload and use USB communication. This would eliminate the IGSD controller  18 , or at least function of the IGSD controller  18 . 
         [0038]    The Doppler radar sensor module  12  is illustrated in detail in  FIG. 2 . The Doppler radar sensor module  12  interfaces to the IGSD controller  18  via a conventional USB connection. The processor  12   a  of the Doppler radar sensor module  12  is a digital signal processor (DSP), such as a Texas Instruments TMS320 series DSP. The radar sensor module  12  uses the radar sensor module processor  12   a  for control, sampling, filtering and data processing. 
         [0039]    The radar sensor module  12  includes an RF Oscillator  34  set for 2.45 Ghz. In the CW mode, this is the frequency of the transmitting signal. In the FM-CW mode, a voltage controlled oscillator (VCO)  36  provides a frequency control voltage to the RF Oscillator  34 . The output of the RF oscillator  34  drives the transmitting antenna  28  via a directional coupler  35 . The signal is coupled to the receiving input, which is mixed by a mixer  38  with the signal from the receiving antenna  26 . The output of the mixer  38  is an IF frequency signal, which is the difference of the transmitted and received signals. 
         [0040]    In the CW mode, the IF frequency signal relates to the relative velocity of the object. In the FM-CW mode, the IF frequency signal relates to the distance due to function of time. The IF frequency signal is amplified by a programmable IF amplifier  39  and fed to a filter circuit  40 , which helps remove noise. The output of the filter circuit  40  is connected to an AID input of the radar module processor  12   a . The radar module processor  12   a  processes the signal, using peak detection, digital filtering, and measurements, providing a digital image. If the digital image meets certain parameters, depending on the set-up, the radar module processor  12   a  could send a complete data stream or just a message. 
         [0041]    It should be understood that other radar designs would work. A frequency of 2.45 Ghz is used here because it is in the ISM frequency band, an unlicensed range. However as a result, power output is limited (˜20 dbm) due to FCC rules. There could be other frequencies that would operate with more accuracy. 
         [0042]    A 4×4 array is used for the micro-strip patch array antennas  26 ,  28  of the present embodiment. The 4×4 array is formed of 16 small squares connected together. PCB cladding material is used as part of the layout. The antenna array mandates the sensor be mounted behind a non-conductive surface. Depending on the frequency, the antenna array will change in type and size. Using an array of 4″×4″, or smaller, one can place the array in a plastic structure or behind a glass panel. Commercially specialized antennas are available which are designed for specific beam patterns. Other optimal antenna configurations are possible, such as phased antennas, different sized arrays or a helical configuration for narrow beam width. With increased sensitivity and increased data processing, one could sense the vital signs of people standing in front of the machine. 
         [0043]    Referring to  FIG. 3 , ultrasonic sensors operate in the basic mode of transmitting a burst of ultrasonic frequency, and then waiting a certain period of time. Following this period of time, a reflected signal, or echo, of the pulse previously transmitted is received. As is well known, the time between transmission and reception is proportional to the object&#39;s distance. Depending on the sensor device, the beam width can be adapted to the application. Using multiple sensor devices and angulation processing improves resolution and accuracy. 
         [0044]    The processor  14   a  of the ultrasonic module  14  is a microprocessor controller (MPC)  14   a , such as a Philips Semiconductors P8051. The processor  14   a  controls operation of the sensor devices and interfaces to the IGSD controller  18  via a conventional USB communications link. 
         [0045]    The processor  14   a  is connected to an ultrasonic sensor  30 . However, the processor  14   a  could control multiple ultrasonic sensors  30 . The limitation is the number of I/O lines on the processor  14   a , and cost. An oscillator  42  oscillates at a frequency set for 38 kHz, matching the sensor specification. The oscillator  42  has two outputs; one is 38 kHz (digital) for the processor  14   a , and the other is a 38 kHz (sin wave) for the transmitters. A gated amplifier  44  controls the length of the burst, plus provide a high voltage output for the transmitter  30   a . The processor  14   a  provides control. If multiple sensors  30  are utilized, it is important to gate each ultrasonic transmitter to turn on one at a time, especially if multiple receivers will detect the reflected signal. 
         [0046]    Although the beam width for the transmitter is narrow, &gt;10 degrees, and the range is short (5 ft to 2 in), the reflections can be multi-directional depending on the object. All 38 kHz signals are ignored beyond an established time limit. These signals could be reflecting off an object greater than 5 ft or caused by a nearby noise source. A combination filter/peak detector  46  eliminates unwanted frequencies and converts the AC signal into a digital signal for the ultrasonic module controller  14   a.    
         [0047]    Data processing by the ultrasonic module controller  14   a  provides data analysis, comparing the 38 kHz signal from the oscillator  42  to the received signal in order to determine range and direction. If there are multiple ultrasonic sensors  30 , the ultrasonic module controller  14   a  performs various triangulation computations for increased accuracy. The ultrasonic sensor module controller  14   a  then sends a data image to the IGSD controller  18 . 
         [0048]    There are different circuits and types of ultrasonic sensors that could alternately be used. The 38 kHz sensor is used here because such sensors are very available. However, higher frequencies could be better for using the Doppler effect for detecting moving objects. 
         [0049]    Both the Doppler radar sensor module  12  and the ultrasonic sensor module  14  are plagued by unwanted reflections. Accordingly, circuitry is provided to set the receive sensitivity of both the modules  12 ,  14 . 
         [0050]    The Doppler radar sensor module  12  works better by first adjusting to its environment, so the programmable IF amplifier  39  is utilized. The radar sensor processor  12   a  is coupled to the programmable IF amplifier  39 . This provides a 4-level (2 bits binary) programmable control for the programmable IF amplifier  39 . 
         [0051]    Referring again to  FIG. 3 , the programmable Ultrasonic receiver  30   b  The ultrasonic sensor processor  14   a  is coupled to a programmable amplifier  47  located between the filter/peak detector and the receiver  30   b . The programmable amplifier  47  is also coupled to the processor  14   a , and has eight (3 bits) levels of sensitivity. The programmable amplifies  47  adjusts the sensitivity of the filter/peak detector  46 . When the IGSD  10  is turned on, or goes through a reset, the IGSD controller  18  sends out a control signal to the programmable amplifies  47  to adjust the receiver  30   b  for optimal sensitivity. Optimal sensitivity is achieved by adjusting the respective received signal, measuring any reflections, and then readjusting and repeating. This continues until optimized, under control of the IGSD controller  18 , because it&#39;s important to limit only unwanted reflections, not true ones. 
         [0052]    After setting optimal operating parameters, if multiple ultrasonic sensors  30  are utilized, the sensors  30  cooperate, using their programmable capabilities. As the reflections move closer to the machine, the ultrasonic sensors  30  are given the command to reduce sensitivities, removing background reflections. There could be cases when one wants the sensors to adjust for maximum sensitivity. 
         [0053]    According to a second embodiment, a second Doppler radar sensor modules  12  is utilized instead of the ultrasonic sensor module  14 . Using two Doppler radar sensor modules  12  provides greater flexibility in design. A Doppler radar sensor will not work behind conducting surfaces, such as steel, aluminum, and the like, and the location is important to sense direction of motion. But with two Doppler radar sensors, one can physically locate them in two different areas with overlapping fields of scan where one wants the player to touch. It allows the object to stay in view of both, or at least one, sensor at any time, resulting in no blind spots. Plus, it provides a three dimensional field of view in certain areas, providing a greater detection of other hand movements that could be used for other than playing the machine. For example, one could request a drink by making a particular hand gesture, and the machine will send a signal to the bar ordering the drink. Although this configuration improves accuracy, the cost is higher. 
         [0054]    Configuration of the Doppler radar sensor module  12  and the ultrasonic sensor module  14  is as follows. Once set for optimal, both sensors  12 ,  14  must report an object in the field of sensing to start the process. If one or both sensors  12 ,  14  report an object getting closer, the ultrasonic sensor module  14  reduces its output to check. With more control over the ultrasonic sensor module  14 , one can reduce the number of reflections because the distance the signal can be received from the source has been limited per the square law rule. If a valid reflection is sensed, the Doppler and ultrasonic sensor modules  12 ,  14  re-adjust and then re-verify. This repeats until the object is in front of the gaming machine by a player distance. To maximize people interaction with the machine, one could use different attract visuals and sound depending on the distance of the object sensed. Absent software analysis of the motion of the detected object, the IGSD  10  does not know whether it has detected a human, or whether it has detected some other object, such as a vacuum cleaner. With both sensor modules  12 ,  14  verifying each other, accuracy is improved. 
         [0055]    Once there&#39;s an action to begin play of the machine, such as by insertion of a coin, the IGSD  10  knows it has detected a human. The application sends commands to the Doppler radar sensor module  12  via the controller to change the transmitting and receiving parameters to focus on the area between the player and the touch area. If the touch area is very close to the sensor modules  12 ,  14 , the ultrasonic sensor module  14  is used to sense the touch, but the Doppler radar sensor module has already notified the IGSD controller  18  that a hand or arm is approaching. 
         [0056]    A top-box  50  is illustrated in  FIGS. 4   a  and  4   b . The top-box  50  is a mechanical structure located above a main cabinet or main game area of a gaming machine (not shown). Top-box designs are used for player attraction and bonus game play, as are well known. There are many types of images displayed on top-boxes, such as spinning wheels, rotating reels, mechanically animated devices or other displays. Some top-box displays have a non-planar shape, such as a hemispherically formed screen  52 . In one example, as illustrated in  FIG. 5 , the image spins or rotates as part of a bonus game. The player can cause the image to stop by touching the image, or extending the player&#39;s arm toward the image, but not making actual contact with the actual image. 
         [0057]    According to the present invention; the Doppler radar sensor module  12  is located above a video projection unit  54  inside the top-box  50 . Because the surface of the screen  52  is made of rear projection material, the screen  52  has a clear field of view towards the player. The ultrasonic sensors  30  are installed around the bottom of the display and provide additional coverage if the Doppler radar sensor module  12  has a so-called dead spot near the edges of the screen  52 . 
         [0058]    Other top-box designs can be in the form of mechanical doors. The player points to one of the doors and/or touches the door; which opens to reveal the amount of the bonus. In this top-box design, the Doppler radar antennas are mounted above the top-box doors, and a respective one of the ultrasonic sensors  30  is located next to each door. The host system  24  notifies the IGSD controller  18  that the game is in a bonus mode. The IGSD controller  18  begins to monitor and translate the data streams from the sensor modules  12 ,  14 . In this example, the doors are too far from the player, so the player is required to point to the door. Data from Doppler radar sensor module  12  shows motion and a set direction. The ultrasonic sensor module  14  shows position and a set direction. Triangulation confirms the angle and set direction. Motion stop and data is verified. The IGSD controller  18  sends the result to the host controller  24 . 
         [0059]    Typically gaming machines have a silk-screened glass panel below the main play area called the belly glass. Some gaming machines have another one above the main play area called the top glass. Because these glass panels typically go through a silk-screen process, it would be very difficult to use it as a touch-sensor, especially if these touch-sensor/glass panels required a wired connection. This would result in the disconnecting and connecting of the glass panels every time the machine is accessed for troubleshooting or the glass panel is replaced. Using the IGSD  10  of the present invention, no direct connection to the glass panel is required. The Doppler radar sensor module  12  is placed behind the glass panel, and one is able to use the glass panel as a player input. 
         [0060]    Another use of the IGSD  10  is for player attraction. Gaming machines use a combination of visuals and sounds to attract players to the machines. With the IGSD  10 , one can have a dynamic attraction. The IGSD  10  can sense people walking by the gaming machine, or stopping to look. This in turn can cause a change in the visuals and sounds, attracting a possible player. Sensing the position and direction, the gaming machine would again change the visuals and sounds as the person nears the machine. Gender can be determined, which enables a different set of visuals and sounds. 
         [0061]    In a third embodiment, only a single Doppler radar sensor module  12  is utilized, no ultrasonic, or other sensor. The single Doppler radar sensor module  12  can detect any object in its field of sensing, moving or range and motion, depending on microwave type. The single Doppler radar sensor module  12  will sense motion, speed and direction as an object approaches the machine. It could be used as an object sensor, which would be used to change attract modes. It is unable to distinguish a human from an inanimate object, unless the sensor has the sensitivity, and the IGSD controller  18  has the computing power, to be able to detect heartbeat by sensing the blood flow in the arm or hand, but, such would be a relatively complex configuration. 
         [0062]    For example a top box display could respond to the approaching object, with a welcome screen or a preview of a bonus play. The only way to verify the object is a player is to use the attract mode changes, but wait until the host  24  detects the start of a game, such as upon insertion of a coin, before using it as a touch sensor. The disadvantage of the simple configuration compared to configurations with multiple sensors is the possibility of blind area. These are areas within the field of sensing that motion detection can be easily blocked, so the location of the sensor is important. Also, the touch area cannot be too close to the sensor because the Doppler radar sensor module  12  typically cannot detect close objects, such as those within 1 ft. The main advantage of this simple configuration is the cost and the size of the sensor module. 
         [0063]    An embodiment utilizing an IR camera sensor  59  is illustrated in  FIG. 6 . The IR camera sensor  59  includes an IR camera sensor processor  59   a  coupled via an LED driver  60  to an IR emitter array  62 . The IR camera sensor  59  further includes an IR camera  64 , also coupled to the IR camera sensor processor  59   a . The most common configuration of the LED emitter array  62  is a circle of LEDS around the lens of the IR camera  64 . The IR camera  64  has several manual or programmable features, such as focus, sensitivity, and the like. An application program in the IR camera sensor processor  59   a  provides noise filtering, gray level conversion, and detection. 
         [0064]    The IR emitter array  62  floods the area around the machine with infrared light. To a human, this light is invisible, but not to the IR camera  64 . The human eye acts like a mirror to the IR wavelength. When looking at the machine, the IR light reflects off the retina of the eye, and the lens of the eye focuses this reflected light towards the IR camera  64 . The IR camera  64 , being sensitive to IR light, will sense reflected light, and the IGSD controller  18  can determine, via software application, if the received IR light is actually an eye reflection. 
         [0065]    The IR camera  64  can also be used to detect motion, using angular processing as reflections move. However, it cannot accurately determine distance. The IR camera sensor  59  would appear as another device connected to the IGSD controller  18 . The IR camera sensor  59  would be used in conjunction with any of the above described systems. 
         [0066]    Alternatively, a standard camera, also designated  64 , can be utilized to detect human form. All of this is to determine if the object detected for motion is actually a human player, rather than some inanimate device 
         [0067]    A final embodiment utilizing an infrared laser scan sensor  70  is illustrated in  FIG. 7 . The infrared laser scan sensor  70  is preferably utilized in conjunction with the ultrasonic sensor  30 , discussed above. The infrared laser scan sensor  70  is capable of being mounted in small areas. It can be mounted behind metallic surfaces, although it would require a small opening in the surface. The opening could be covered with plastic or glass, provided the covering is not opaque to the infrared light. 
         [0068]    The infrared laser scan sensor comprises an infrared projector  72  and an infrared detector  74 . The infrared projector  72  comprises: (1) an IR or red laser  76 ; (2) a reflector device  78 , such as a digital micro-mirror device (DMD), as provided by Texas Instruments, or a MEMS (Micro-Electrical mechanical system) scanner; and (3) a lens  80 . The projector  72  further includes a scanner interface  82  and a laser driver  84 . The scanner interface  82  can be digital drivers, or a DAC, depending on the type of reflector device  78 . The laser module  76  can be continuous, pulsed or modulated, all under control of the processor  70   a.    
         [0069]    The reflective device  78  is extremely small, and requires a narrow beam. The lens  80  assures the light beam covers the entire surface to be scanned. 
         [0070]    The infrared projector  72  beams light into a prismatoid shaped pattern in front of the sensor opening. As is known in the art, the DMD and MEMS use mechanical action to sequentially reflect light from an X-Y array of reflectors under control of the processor  70   a . The reflector located in the upper left corner is first activated, sending the reflected beam out toward a first point in space. Then the next reflector is activated, sending the reflected beam toward a second, adjacent point in space. This continues until each reflector has been activated, at which time the process is repeated. 
         [0071]    The high rate of switching between individual reflectors of the reflector device  78  causes a laser beam to be reflected in an X-Y pattern through the lens, forming a prismatoid field of sensing. A physical object is in this field is be scanned by the laser. The infrared detector  74  is coupled to the processor  70   a  by a programmable amplifier  86  and a filter/peak detector  88 . The detector  74  detects the reflection of the laser spot (beam) off of the object, generating an output trigger signal. This trigger signal with information identifying the particular reflector activated at that time indicates the location of the illuminated point of the object. The IR detector  78  has a wide field of sensing, and a programmable amplifier  86 , under control of the processor, adjusts the output of the detector  78 . 
         [0072]    A hand in the field of scanning could generate hundreds of triggers and each trigger will appear at different X-Y locations. The IGSD  10 , or the host  24  would use angular processing providing motion detection and location, but referencing these as if they were on a single plane of the three dimensional space. Accordingly, the ultrasonic sensor  30  would work in conjunction with the infrared laser sensor  70   
         [0073]    Relative position is determined by using the X-Y coordinates as a reflected signal is detected. Motion can be determined be comparing the relative changes in the reflected signals or by using the Doppler effect. One feature of the laser scan sensor  70  is its ability to outline objects in the field of sensing, such as to distinguish a human outline from that of a cart. The laser scan sensor  70  can also determine the number of people standing in front of the machine. This feature can be used for very interesting attract modes. 
         [0074]    Alternatively, an IR camera system could be used to detect the X-Y location of the reflected beam and then use the next set of scans to determine angular movement, although this would be more complex. 
         [0075]    The beam scan gets larger further away from the source, like an inverted pyramid. When the ultrasonic sensor detects the object is in the virtual touch area, and the infrared laser scan sensor sends the correct X-Y coordinate, the system determines the touch is valid. 
         [0076]    While the specific embodiment has been illustrated and described, numerous modifications come to mind without significantly departing from the spirit of the invention, and the scope of protection is only limited by the scope of the accompanying claims.

Technology Category: g