Abstract:
A portable searchlight with a focused beam operating both in the infrared and visible portions of the spectrum with a range of approximately 400 meters includes telescopic lens system integrated with an illumination system. The beam of the searchlight and the telescopic lens are automatically aligned to both focus on the distant object. The telescopic lens system is combined with a digital camera system and an LCD display. The searchlight includes an eyepiece lens so that a user may choose to either view a display screen or use the eyepiece lens to optically observe the field of view. Because the image is digital, the invention allows for the possibility of real time imaging processing in the portable device and/or the ability to transmit image data to remote receivers.

Description:
RELATED APPLICATIONS  
       [0001]     The present application is related to U.S. Provisional Patent Application, Ser. No. 60/546,812, filed on Feb. 23, 2004, which is incorporated herein by reference and to which priority is claimed pursuant to 35 USC 119. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention pertains generally to illuminating optical systems, AND more particularly, to a nighttime, long-range, portable illuminating device having an integrated telescopic imaging and viewing systems.  
         [0004]     2. Description of the PriorArt  
         [0005]     Handheld lighting devices with focused beams or spotlights or searchlights, whether battery-powered or line-powered, are commonly used by military, law enforcement, fire and rescue personnel, security personnel, hunters and recreational boaters among others for nighttime surveillance in any application where a high intensity spotlight is required. The conditions of use are highly varied, but generally require the light to deliver a desired field of view at long distances, be reliable, durable and field maintainable in order for it to be practically used in the designed applications. Typically the light is hand carried and must be completely operable using simple and easily access manual controls which do not require the use of two hands.  
         [0006]     In prior art xenon short-arc searchlights or illumination systems, whether handheld, portable or fixed mounted, the luminance distribution of the arc has been positioned facing in the direction of the beam (cathode to the rear), to provide a uniform beam pattern when the arc is at the focal point of the parabolic reflector. When the luminance distribution of the arc is positioned in this manner, a majority of the light output is collected in the low magnification section of the reflector and in a slightly divergent manner in the far-field. When the beam is diffused into a flood pattern, a large un-illuminated area or “black hole” is projected. Reversing the lamp position so that the full luminance distribution of the arc is in the high magnification section of the parabolic reflector produces a more concentrated beam in the near- and far-field and hence greater range can be achieved. Additionally, when the beam is diffused into a flood pattern no characteristic “black hole” of prior art configurations is produced. When the arc is moved slightly beyond (or slightly rearward of) the reflector&#39;s focal point, the combination of a placing all available light in the high magnification section of the reflector and collecting it in a slightly convergent manner produces roughly twice the operating range as a conventional anode-forward device.  
         [0007]     A device which remedies the foregoing limitations, but which is still only an illumination unit with no enhanced viewing components is shown in Jigamian, U.S. Pat. No. 6,702,452 (2004), and U.S. patent applications 20050007766 (2005), 20040042211 (2004), 20040027824 (2004), which are incorporated herein by reference.  
         [0008]     Telescopic viewing systems also employing imaging and night vision capability are well known. However, a need exists, especially in military and law enforcement applications, for a long-range, portable system capable of illuminating and observing objects at a range of approximately 400 meters and farther, using visible or infrared illumination and for providing for the possibility of image real time processing in the portable illumination unit.  
       BRIEF SUMMARY OF THE INVENTION  
       [0009]     In one aspect, the invention is a compact device that can illuminate objects much farther than the eye can see or reliably resolve. The ability to clearly observe a scene at ranges of approximately 400 meters and farther at nighttime or in low-light conditions or other situations of impaired visibility gives the user a significant operational advantage. It is contemplated that such a system will be beneficial in military, law enforcement, border-patrol, security, and maritime vessel applications, and other applications where a portable, compact device of this kind is desired.  
         [0010]     Separate systems for illuminating from a great range while simultaneously observing using a different apparatus, such as a telescopic viewing and imaging system, can be cumbersome, unwieldy and difficult to operate. One particular problem is finding and maintaining alignment and focus on a particular object that is separately illuminated by another system. Other advantages become apparent particularly in infrared illumination applications. More specifically, focusing with infrared light requires more precise alignment angles for a lamp and a lens as just a couple of degrees difference will result in a loss of a large amount of available light energy.  
         [0011]     The present invention is also characterized as a compact, handheld, portable device that can illuminate objects at distances greater than the naked eye can reliably see. The device further provides illumination in either the visible spectrum or infrared spectrums. A telescopic lens system integrated with the illumination system has sufficient capability to view objects from a great distance in both the visible and infrared spectrums. The telescopic lens system can alternatively be applied to a digital camera system. More specifically, the digital camera system may contain an image sensor, such as a charge-coupled device (CCD), and a means to display an image such as a LCD display. The invention alternatively includes an eyepiece lens such that a user may choose to view a display screen or use the eyepiece lens to optically observe the field of view. Because the image is digital, the invention allows for the possibility of real time imaging processing in the portable device, so that the displayed image can be artificially enhanced according to the control of the user to optimize visualization of the image or a selected part thereof. The invention also includes the ability to transmit image data to remote receivers as part of a wireless battlefield.  
         [0012]     The device of the present invention has a light source or a lamp, such as a xenon arc lamp or other plasma lamp; or alternatively the device comprises a high intensity discharge lamp (HID) such as a mercury vapor, metal halide or high pressure sodium lamp. The device of the invention is further characterized in that light energy is produced from a highly concentrated plasma ball, or illumination source, and precisely radiated about a reflector&#39;s optical axis of symmetry, wherein light waves can achieve great illumination distances. Alternatively, if a plasma lamp is used, the plasma lamp will have circuitry associated with it to obtain proper voltages for creating and maintaining a glowing plasma. Also, the device including the lamp will have a mechanical configuration including a lamp holder that allows for relatively quick replacement in the field while maintaining the precise alignment necessary for long-range operation.  
         [0013]     Also, the lamp is mounted within the searchlight so that the anode of the lamp is in the rearward position relative to the direction of a beam projected by the searchlight so that the field of illumination of the beam is slightly convergent and more concentrated and therefore delivers a much longer range of operation. This configuration will prevent the “black hole” effect associated with other configurations such as cathode to the rear.  
         [0014]     The device of the invention further includes a telescopic sight having one or more objective lenses. It is contemplated that one objective lens could be used for both visible light and infrared applications or separate lenses provided depending on the application. The device of the invention also includes other optical elements as needed for focusing and collimating light. The searchlight can be highly collimated to deliver a useful spotlight over a mile away. According to one embodiment, an eyepiece is employed by a user to view an image plane. In an alternative embodiment, an image sensor such as a charge-coupled device (CCD) having a pixel array is employed. The image sensor will accumulate pixel data as electrical charge and transfer the pixel data to storage locations during a frame cycle. Additional circuits will convert the pixel data to a video signal that can be displayed on a video screen of the device. The video signal may also be transmitted to remote locations. The image sensor will either solely produce monochrome images or color signals may be constructed from the image sensor.  
         [0015]     In yet another aspect, the present invention may be characterized as a compact self-contained device having illuminating, telescopic viewing and imaging capabilities, the device comprising: a searchlight housing having a top portion and a side portion; a view finder having an eyepiece and having an adjustable position with respect the searchlight housing, wherein the view finder is pivotable about a position with respect to the top portion of the searchlight housing. In this manner, the view finder has a stowed position and an adjustable deployed position. The device also includes a video display having an adjustable position with respect the searchlight housing, wherein the video display is pivotable about a position with respect to the side portion of the searchlight housing; and a telescopic lens assembly integrally connected to the searchlight housing, wherein the telescopic lens is configured to receive light from a distant scene that is illuminated by the device.  
         [0016]     The device of the invention optionally provides that the view finder, video display and the telescopic lens assembly are modular components for ease of manufacture and replacement of the components. As in other embodiments described herein, telescopic lens assembly is capable of magnifying objects in the distant scene up to approximately 20× and farther. The video display may alternatively be an LCD display. A filter may also be provided, positioned forward of the searchlight housing for blocking wavelengths of light up to infrared wavelengths, namely a low pass filter with a cutoff at the visible frequency and higher. In this way the device becomes an infrared searchlight and telescope.  
         [0017]     While the apparatus and method has or will be described for the sake of grammatical fluidity with functional explanations, it is to be expressly understood that the claims, unless expressly formulated under 35 USC 112, are not to be construed as necessarily limited in any way by the construction of “means” or “steps” limitations, but are to be accorded the full scope of the meaning and equivalents of the definition provided by the claims under the judicial doctrine of equivalents, and in the case where the claims are expressly formulated under 35 USC 112 are to be accorded full statutory equivalents under 35 USC 112. The invention can be better visualized by turning now to the following drawings wherein like elements are referenced by like numerals. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0018]      FIG. 1A  is a front perspective view of the searchlight as seen from the front left side of the searchlight and showing the viewing components deployed for operation.  
         [0019]      FIG. 1B  is a rear perspective view of the searchlight as seen from the front left side of the searchlight and showing the viewing components deployed for operation.  
         [0020]      FIG. 2  is a schematic block diagram of the viewing and display portions of the system of the present invention capable of long-range illumination and observation. 
     
    
       [0021]     The invention and its various embodiments can now be better understood by turning to the following detailed description of the preferred embodiments which are presented as illustrated examples of the invention defined in the claims. It is expressly understood that the invention as defined by the claims may be broader than the illustrated embodiments described below.  
       DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0022]     Now referring to  FIGS. 1A and 1B , a compact, handheld device  10  of a preferred embodiment of the present invention is illustrated in front and rear perspective view. Eyepiece viewer  12  has a deployed and a stowed position, which is shown in  FIGS. 1A and 1B  in the stowed position. Eyepiece viewer  12  is optically coupled to the telescopic lens assembly  14  and can be rotated upward to be deployed at a user-selected angle of convenience or rotated downwardly to lie in a flush configuration within a receiving cavity  13  defined in body  11  of device  10 . The actual image which is being optically received by telescopic lens assembly  14  can be directly viewed by the user through eyepiece viewer  12 .  
         [0023]     Similarly, telescopic lens  14  has deployed and stowed positions. Lens assembly  14  rotates out of a cavity  24  defined in body  11  for flushly receiving lens assembly  14  as a protective door  17  also moves or rotates out. The mechanical linkage by which such movements can be realized are conventional and not further detailed here. Lens assembly  14  will be forwardly directed when deployed and will be substantially aligned with or parallel to the optical axis of illumination head  15  or the beam of the device  10 . Although lens assembly  14  will be normally aligned to coincide with the beam position at the preferred range, e.g. 400 m, it is to be understood that other ranges can be accommodated and a mechanism to allow variable alignment of lens assembly  14  in the field to virtually any beam position can be provided using ordinary design principles and modifications.  
         [0024]     Lamp housing  15  contains a lamp and reflector apparatus internally (not shown). Rotatable bezel  16  is used to vary the beam spread of the illumination device of the present invention by effecting relative movement of the reflector with respect to the light source within lamp housing  15 . The details of lamp housing  15  and its lamp and reflector apparatus are detailed in the incorporated U.S. Pat. No. 6,702,452 (2004), and U.S. patent applications 20050007766 (2005), 20040042211 (2004), 20040027824 (2004). Filter  18  is mounted in bezel  16  and is selectively included to filter out undesired wavelengths of light, e.g. to provide an infrared beam only or other selected portion or portions of the spectrum.  
         [0025]     Video display  22  allows the user to selectively view an image scene or a selected portion of the scene captured by lens assembly  14 . Video display  22  also has deployed and stowed positions. Display  22  rotates out of a conforming cavity  19  defined in body  11  of device  11 , which allows display  22  to remain flushly within the envelope of body  11  for protection and storage. When deployed, display  22  swings out from body  11  and can be oriented on a conventional swivel connection to be angularly inclined at an arbitrary user-selected angle for convenient viewing. Display  22  may be any type of video display now known or later devised, including LCD, plasma displays, or LED displays.  
         [0026]     Referring now to  FIG. 2 , a simplified schematic of a circuit  20  of the present invention is shown. Long-range illuminator  10  has an optical filter  18  and projects a high intensity beam  36  of light. System  20  may be combined with separate or interchangeable telescopic lens assemblies  14  for infrared and visible light; or a single lens assembly  14  can be configured to handle both modes. Lens assembly  14  has objective lens  42  and collimating lens  44 , as well as focusing lens  52 . Although single lenses have been reference, it must be expressly understood that lens assemblies can be employed in each case and that the optical arrangement in device  10  can be readily modified to assume other configurations according to conventional design choices.  
         [0027]     A user  55  can view the distant scene focused on image plane  54  through eyepiece  24 . Partially silvered mirrors  46  and  48  are used to send the image to a collecting lens  40  and detector or charge coupled device  58 , which is employed to capture a two dimensional image. In the event that device  58  is an analog imaging camera, its output may be coupled to analog-to-digital converter  62 . A video output  64  from converter  62  is produced that may be transmitted by other appropriate digital transmission equipment to remote locations. The video signal may also be bidirectional so that the same digital transmission equipment coupled to device  10  could receive information, including graphic information from a remote site and display the same on display  22 . The reconstructed digital image captured by lens assembly  14  is viewed on video display  22 .  
         [0028]     It must be understood that additional circuitry may be included to process the digital image produced by detector  58  and/or converter  62 . In the case of an infrared image, the only image which will be visible will be displayed on display  22  after being converted into a visible video signal by display  22 . Display  22  or detector  22  may include circuitry or digital processing capability according to well known conventional principles to select, edit, enhance or reduce various aspects of the received visual image. For example, false coloring of an image to represent the temperature of various portions of the image or false coloring to exaggerate the contrast of some portions with surrounding portions can readily be included. In addition, variable electronic magnification or zoom can be added to the variable optical magnification of lens assembly  14  subject to user control. Motion detection of the image can also be included, whereby any portion of the image which is moving relative to other portions of the surrounding image is highlighted or falsely colored to be readily visually identified.  
         [0029]     Although in one embodiment image processing is contemplated as being performed in real time in the device  10 , it is also within the scope of the invention, where output  24  is bidirectional, that image processing can be performed at a remote station and then returned in modified form to device  10 . Such remote image processing may include selective mixing with other images derived from other devices  10  in the field or combined with information generated or collected at the remote site. In such a situation, display  22  could be modified to be an input/output device, such as a touch screen. In this manner the displayed scene on display  22  from wherever it may be derived, allows for interactive input by the user in the field. The remote fire control command center may, for example, process the image from device  10  for suspected targets, one or several of which will then be selected by touching the screen by the user in the field, which selection is then communicated back to the remote fire control command center, which in turns directs appropriate fire control to other units in the theater. Device  10  can thus be used in this manner of one of many interactive detection and input devices in an integrated battlefield fire control system.  
         [0030]     Many alterations and modifications may be made by those having ordinary skill in the art without departing from the spirit and scope of the invention. Therefore, it must be understood that the illustrated embodiments have been set forth only for the purposes of example and that it should not be taken as limiting the invention as defined by the following claims. For example, notwithstanding the fact that the elements of a claim are set forth below in a certain combination, it must be expressly understood that the invention includes other combinations of fewer, more or different elements, which are disclosed in above even when not initially claimed in such combinations.  
         [0031]     While the particular Portable Long-range Searchlight with Telescopic Viewing and Imaging Systems as herein shown and disclosed in detail is fully capable of obtaining the objects and providing the advantages herein before stated, it is to be understood that it is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended to the details of construction or design herein shown other than as described in the appended claims.  
         [0032]     Insubstantial changes from the claimed subject matter as viewed by a person with ordinary skill in the art, now known or later devised, are expressly contemplated as being equivalently within the scope of the claims. Therefore, obvious substitutions now or later known to one with ordinary skill in the art are defined to be within the scope of the defined elements.