Abstract:
Method for jamming or affecting the quality of photo and video recording, the method comprising illuminating the area, collecting light reflected or scattered from optical components such as camera lenses, amplifying them, and reversing the amplified beams back to the camera with phase conjugating mirror. The method may further comprise image acquisition and processing for identifying unwanted optical components and sensors, and electronically pointing and focusing a laser beam on said components and sensors.

Description:
RELATED APPLICATIONS 
       [0001]    This application claims priority to Provisional Application No. 61,843,001 filed Jul. 4, 2014, the contents of which are relied upon and incorporated herein. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to privacy and counter-piracy systems with respect to photo and video recording. 
       BACKGROUND OF THE INVENTION 
       [0003]    There is a growing need for detection of cameras and preventing them from taking photos and videos in restricted or forbidden areas. Such prevention is required for security, counter-piracy, privacy and other reasons; some of those situations are listed below: 
         [0004]    Security (government/civil/military)—anti-drone (prevent drones from capturing video/photography of targets/subjects), public demonstrations, government buildings/facilities, potential terrorism targets, i.e. military installations, aircraft, ships, dockyards, weapons storage facilities, nuclear power plants, underground subway stations and civil aviation installations, dams, train stations, airports, aircraft (private/commercial), national parks. 
         [0005]    Piracy/copyright protection—cinemas, venues, halls, stadiums, tourist attractions, concerts, shows, clubs, casinos, hotels, places of worship, museums, privately owned areas (i.e. homes), shopping malls, businesses or anywhere where “no photography” signs are posted. 
         [0006]    Privacy—celebrities, public figures, government officials, anyone requiring anonymity. 
         [0007]    New technologies such as Google glasses make recording of images and videos even more intrusive. 
         [0008]    Currently there are no technologies that prevent unauthorized photo/video recording. The objective of the present invention is to provide means for camera detection and jamming sensors at least to a degree where the acquired images lose their informative, aesthetic or commercial value. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0009]      FIG. 1  shows camera detection and jamming technique based on phase conjugating (wave-front reversing) mirror. 
           [0010]      FIG. 2  shows jamming of imaging capability of camera by a laser beam. 
           [0011]      FIG. 3  schematically shows counter-recording arrangement using a glasses with frame-mounted jamming laser. 
           [0012]      FIG. 4  schematically shows the concept of jamming cameras in a movie theater. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0013]    Before explaining the disclosed embodiment of the present invention in detail it is to be understood that the invention is not limited in its application to the details of the particular arrangement shown since the invention is capable of other embodiments. Also, the terminology used herein is for the purpose of description and not limitation. 
         [0014]    In the preferred embodiment shown in  FIG. 1 , the area where taking images and videos is prohibited is illuminated by a light beam  101  from a source  100  of a wavelength and intensity that are safe for the human eye. Said light beam diverges during propagation as schematically shown in  FIG. 1  by expanding wave-front of the beam  102 , thus reaching a camera lens without the need of special alignment. Several illuminators can be used for the purpose of covering a desired area or the light beam can be scanned through the area. The light beam  104  reflected from the camera optics  103  propagates expanding in space as schematically shown in  FIG. 1  by arrows  104  and expanding wave-front  105 , and is captured by the optical subsystem  107  of the camera detection and jamming system (CDJS). CDJS further comprises a laser amplifier  114  and optical phase conjugating mirror (OPCM)  111 . The amplifier  114  amplifies the beam captured by the optical subsystem  107  and propagates said beam  110  to OPCM that reflects the beam  112  back into the amplifier  114  by conjugating its phase (reversing its phase-front). Said phase conjugated and further amplified beam  113  propagates back focusing onto the camera lens as schematically shown by the arrows pointing along propagation direction  116  and its phase fronts  117 , and providing power density large enough to jam or, if required for the specific application, to damage it. The amplifier may be on or off depending on whether or not camera detection shall be accompanied by jamming.  FIG. 2  shows the effect of jamming a CCD with a laser beam. 
         [0015]    Operation of OPCM mirrors is based on recording of dynamic holographic gratings in nonlinear optical materials. In a preferred embodiment, said nonlinear optical material is a liquid crystal. In another preferred embodiment, said nonlinear optical material is a photorefractive material. 
         [0016]    The illumination source  100  and the camera detection and jamming system can be mounted on stationary or mobile platforms, depending on the application. For example, one or both of them can be mounted on any form of transportation (i.e. a vehicle/boat/plane/motorcycle/bicycle/train), on-person, embedded in a cell-phone, glasses, headset, handbag, or other personal item, and may be powered by a battery. 
         [0017]    In another embodiment of the current invention the self-targeting system described above is complemented or replaced by other methods of camera detection such as image processing. For example,  FIG. 3  shows a Google Glass  301  comprising a mounted camera  302  countered by anti-recording glasses  304  comprising a camera  305  and a laser beam generation and directing system  303 . The images taken with the camera  305  are processed to produce information on camera lens location of the Google Glass, and the laser is activated and focused on the camera to jam it as required. The beam direction system may comprise rotating Risley prisms, phased arrays, micro-electro-mechanical systems, and a variable focus system. 
         [0018]    The camera detection system can be further enhanced to discriminate cameras from each other or from other objects such as eyes. The discrimination system can use spectral analysis of light reflected and/or scattered from objects, and other signatures of imaging systems such as those that reflect the complex multicomponent nature of camera lenses. Note that the image processing system can be passive as well as active, requiring acquisition of actively illuminated images. Such image processing systems are well known in the art. For example, they are now routinely incorporated in even mobile phone cameras to identify heads even in the group of people. 
         [0019]    The selective targeting systems of the current invention allow monitoring the area with low power beams, and using higher power focused beams for jamming. Thus, if the area contains sensors that need to be protected (such as eyes), the high power beam does not affect them. Another advantage of using low power illumination for detection is power saving that is essential for mobile/portable systems. In another preferred embodiment, the active imaging using laser illumination particularly at wavelengths invisible to the human eye, is activated upon a signal from passive imaging results. Then the targeting systems are activated upon a positive signal from the active imaging results. 
         [0020]    The self-targeting systems of the current invention can be fast and compact by using electrically variable transmission systems for dynamically controlling the power of radiation. Particularly, liquid crystal variable transmission systems known in the art offer low-power/low-voltage operation compatible for portable systems. The power of the laser beam can thus be set to different limits at different stages of the system operation or for different purposes. For example, the targeting laser beam can disable the camera, jam it, or just create an area where the jamming merely affects the informative or aesthetic features of the images. Also, tuning the laser beam power may be necessary when the target cameras are at different distances. 
         [0021]    Similarly, liquid crystal variable focal length lenses would allow focusing on objects with low-power/low-voltage electrical requirements. Electro-optical beam steering systems for directing laser beams can also be based on liquid crystal technology. 
         [0022]    Note that the invention is not limited to cameras sensitive to visible and near infrared wavelengths only, but encompasses sensors and imaging systems for longer wavelengths, including thermal sensors. 
         [0023]    The case of an important particular application related to piracy is shown in  FIG. 4 . The projector  401  radiates light  402  illuminating the screen  408 . The screen  408  thus becomes a source of illumination covering all theater area as shown by rays  403 . A camera  404  is thus illuminated by rays  406  emerging from different portions of the screen  408 . The light rays  407  reflected or scattered from the lens of the camera  404  makes it thus visible for imaging by sensor cameras of CDJS  409 . The image processing system  410  identifies the camera (or cameras) and identifies the objects (people heads, earing, etc.) that need to be excluded from laser targeting. The information is on camera location is then provided to the electrically controlled laser beam scanning and focusing systems  411  for targeting. Using phase arrayed scanning system well known in the art allows to direct the laser beam  412  on the camera or a number of cameras only avoiding subjecting any intermediate areas to the beam. A single laser would allow targeting sequentially a multitude of cameras. 
         [0024]    Although the present invention has been described above by way of a preferred embodiment, this embodiment can be modified at will, within the scope of the appended claims, without departing from the spirit and nature of the subject invention.