Abstract:
An apparatus for producing signals by means of radiation, for controlling musical instruments, image producing devices, video games, computer games and the like, comprises sensors sensitive to radiation directed towards them from points of sensing spaces, selectively to produce the aforesaid signals, and emitters for conveying radiation to elongated emission spaces.

Description:
RELATED APPLICATIONS 
     This application is a file wrapper continuation application of U.S. Ser. No. 07/776,669, filed on Oct. 15, 1991, which is now abandoned. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of The Invention 
     This invention relates to apparatus and processes for detecting objects, especially for operating musical instruments, video games and the like. 
     2. The Prior Art 
     Apparatus for operating musical instruments by radiation has been described in the prior art. One such apparatus is described in EPA 89304784.5, wherein it is also taught that the apparatus may be used to generate optical images and the like, in general with the aid of a microcomputer, to control game-playing devices. 
     SUMMARY OF THE INVENTION 
     This invention refers to apparatus in which radiation detectors, or sensors, are reactive to radiation from objects entering sensing beams associated with the detectors. An apparatus according to the invention comprises a sensing beam or screen, viz. a screen-like space which comprises the points such that radiation originating therefrom is detectable by a radiation detector or sensor. An array of screens can be arranged to form an enclosed inner space in which a person moves. The array may be continuous, or contiguous beams merging the ones into the others, or may be nearly continuous, the gaps between contiguous sensing beams being relatively minor in size, or may comprise overlapping sections, wherein contiguous sensing beams overlap. The sensing beams preferably have nearly rectangular or trapezoidal cross-sections. They are preferably slanted, with respect to the vertical, and if the screen is a closed one, they are slanted inwards toward the area in which the person operates, by an angle that is comprised between 0° and 10° and preferably between 3° and 7°. The sensors are activated by penetration of a radiation source or of a body which reflects or diffuses radiation coming from a source. 
     Each sensor generates an electrical signal corresponding to a musical tone, an image, a modification or motion of an image, a game-playing instruction, or an operating signal for controlling any device or interface. It is preferred that the emission and sensing beams overlap. The sensing beams may have different shapes in the vertical cross-section. In the simplest case they will have a flared-out or essentially triangular cross-section-- more exactly, a trapezoidal cross-section which has a very short lower side. However, different shapes may be imparted to the sensing beams, if desired. 
     With the above considerations in mind, the apparatus according to the invention comprises radiation detectors or sensors responsive to radiation and means for conveying to said sensors radiation from elongated sensing spaces or beams. 
     The apparatus will ordinarily comprise a plurality of sensing beams, each associated with at least one sensor. The radiation that is conveyed to the sensor preferably originates from an emitter which is outside said beam and is reflected or diffused towards the sensor by a surface having reflective or diffusive capacities. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be better understood from the description of a preferred embodiment thereof, with reference to the appended drawings wherein: 
     FIG. 1 is a perspective view of an apparatus according to an embodiment of the invention; 
     FIG. 2 is a sectional view of the sensing screen taken on line II--II of FIG. 1; 
     FIG. 3 is a vertical cross-section view of a sensing space, taken on any radial line, e.g. on line III--III of FIG. 2, showing the cross-section of a sensing space and of the parallelepiped which envelopes it; 
     FIG. 4 schematically shows a parallellepipedal envelope which envelops a sensing space; 
     FIG. 5 shows a top plan view of a sensor and an emitter on a support; and 
     FIGS. 6a and 6b schematically show, in perspective view, an example of the emitter and the sensor of FIG. 5, with the top of the support removed for clarity. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In the embodiment herein described, a sensing screen is considered without any reference to the way in which the radiation is produced, e.g. infrared or visible radiation or laser or ultrasound radiation, and so forth. 
     As seen in FIG. 1, an optical controller apparatus 10 according to this embodiment of the invention comprises a number of elongated panel sections 11 or supports arranged in a closed line, specifically, in the schematic embodiment illustrated, a polygon having eight sides. The apparatus can be constructed in a number of ways, and its sections may be foldable or disassemblable, etc. 
     In FIG. 2, which is a horizontal cross-section of the sensing screen taken on plane II of FIG. 1, the sensing screen 13 is shown as being continuous, viz. the sensing spaces 14 border on one another, without the small gaps or the overlaps which, as has been said, could exist. 
     FIG. 3 shows a sensing space 14 which is trapezoidal in vertical cross-section and a parallelepiped 15 which envelops it and has a rectangular cross-section. In this figure, the sensing space 14 is shown as constituting a single unit, which will ordinarily be associated with a given signal. 
     In FIG. 4 a parallelepiped 20 is represented in perspective view. The parallelepiped envelops the entire sensing screen 21. The sensing screen 21 is formed by overlapping portions of the sensing and emission beams. The parallelepiped 20 also includes inactive shaded areas outside the sensing screen, the areas shaded being formed by non-overlapping portions of the sensing and emission beams. 
     FIG. 5 is a general top view of a support for an apparatus according to one possible embodiment, the emitting means being indicated by (a), and the sensing means by (b). Correspondingly, FIG. 6(a) is a perspective view of emitting means (a) of FIG. 5, and FIG. 6(b) of sensing means (b) of FIG. 5. FIGS. 6(a) and 6(b) are shown with the top and one sidewall removed, for clarity. In FIG. 6(b) numeral 60 designates an opening or entrance port through which radiation is received by the sensor, viz., which constitutes the vertex of the sensing beam. 61 designates a mirror surface which reflects the incoming radiation by 90° to the spheric, 50 mm focal length shaping lens 62. Through lens 62 the radiation enters into radiation channel 63, which is provided with mirror surfaces (not shown). These mirror surfaces can be provided in any suitable way, e.g., by vaporizing an aluminum coating on the surface or glued mirror surface. Channel 63 ends with a cylindrical lens 64, which concentrates the radiation on the sensor component such as, e.g., a photodiode 65. 
     The combination of lenses 62 and 64, primarily cylindrical lens 64, are operative for shaping the sensing beam to have a generally thin, screen-like volume (see FIG. 4) in which the cross-sectional thickness is less than the cross-sectional width substantially throughout the beam. 
     Lens 62 is a spherical lens which has uniform magnification or focusing power in all directions in a two-dimensional cross-sectional plane perpendicular to its optical axis. 
     Lens 64 is a cylindrical lens which has magnification or focusing power in a single direction in a two-dimensional cross-sectional plane perpendicular to its optical axis. For example, cylindrical lens 64 as illustrated in FIG. 6(b) magnifies the beam only in the vertical direction at sensor 65. This being true, the field of view seen by sensor 65, through the combined power of lenses 62 and 64, is spread as illustrated by sensing space 14 in FIGS. 2-3 and 21 in FIG. 4. Mirror 60 merely changes the direction of the optical axis from vertical to longitudinal as shown in FIG. 6(b). 
     The channel 63 desirably has a height comprised between 7 mm and 9 mm and preferably between 7.8 mm and 8.2 mm, a width comprised between 24 mm and 28 mm and preferably between 24.8 mm and 25.2 mm, and a length comprised between 80 mm and 100 mm and preferably between 85 mm and 95 mm. This, of course, is only an example referring to a specific type of radiation, and a great variety of sensors and means for conveying radiation thereto could be used, both in the case of an optical radiation and in the case of other radiations, such as ultrasound etc. 
     The situation in FIG. 6(a) is similar but reversed, whereby radiation leaving a source 66 and passing through shaping lenses 67 and 68 leaves through an exit port or an opening 69 to shape an emission space. 
     It should be stressed once more that the invention relates to any apparatus of the kind described, provided that it comprises radiation detectors, which are sensitive to radiation of any kind directed towards them from points of a sensing space. In such apparatus, the invention can be carried into practice by persons skilled in the art with many modifications and adaptations and the use of many equivalents, without departing from its spirit or from the scope of the claims.