Patent Publication Number: US-2007097351-A1

Title: Rotary menu display and targeting reticles for laser rangefinders and the like

Description:
TECHNICAL FIELD  
      This disclosure relates to displays, menus, and targeting reticles for rangefinders and other aimed optical devices having a field of view or viewfinder.  
     BACKGROUND OF THE INVENTION  
      Handheld laser rangefinders and other aimed optical devices, such as riflescopes, spotting scopes, night vision scopes, binoculars, cameras, and the like often have integrated electronic systems and controls that have user-selectable feature settings. Some known rangefinders and cameras include display devices that are driven by an electronic controller and designed to display an interactive setup menu that allows a user to select from various operational modes or features, depending on environmental conditions and/or the needs of the user. In some such devices, the menu display is viewable through an optical targeting sight or other optical system of the device. In other aimed optical devices, a menu display is viewable in the viewfinder or other optical system of the device, or on an external electronic display panel.  
      The interactive menu systems in known laser rangefinders and other aimed optical devices are often confusing to operate. They may present feature options in a list or table, using several levels of hierarchy or without any meaningful organization. Such menus can be difficult to navigate without a user manual.  
      Laser rangefinders and riflescopes typically include targeting reticles. Some known targeting reticles are generated by an electronic display device, such as a liquid crystal display (LCD) positioned in the optical path. Some LCD displays may be illuminated by light reflected off the surface of the display elements, while others may provide only opaque display elements that are visible in the field of view. Various other display technologies, such as etched side-illuminated displays, organic light emitting diodes (OLED), fiber optics, and others are also known for generating reticle displays in the field of view and may be useful for certain embodiments of the inventions disclosed herein.  
      Electronic displays in rangefinders may facilitate the display of variable digital data, such as a range-to-target readout, in the field of view of the optical device. Menu displays, digital readouts, and reticles are also known to be patterned in a single LCD display panel in a rangefinder. However known rangefinders continuously display range data and other information adjacent the reticle, which the present inventors have found tends to obscure the field of view and inhibit target acquisition.  
      The present inventors have recognized a need for improved menu systems and methods of operating interactive menus and data displays in a rangefinder or other aimed optical device; and for improved reticle display systems for aimed optical devices. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a perspective view of a laser rangefinder according to a preferred embodiment;  
       FIG. 2  is a view of a display of the rangefinder of  FIG. 1  with all menu display elements and targeting display elements shown for purposes of illustration;  
       FIG. 3  is a view through an aiming scope of the rangefinder of  FIG. 1  showing a first menu selection of the display of  FIG. 2 ;  
       FIG. 4  is a view through the aiming scope of the rangefinder of  FIG. 1 , showing a targeting reticle display and leaving all menu icons of  FIG. 2  turned off;  
       FIG. 5  is a view through the aiming scope of the rangefinder of  FIG. 1 , with the display showing a targeting reticle and a display readout of measurements to a target at which the rangefinder is aimed; and  
       FIGS. 6A-6M  are selectable reticle configurations of the targeting display elements shown in  FIG. 2 . 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
      In accordance with one embodiment, a handheld rangefinder  10  is depicted in  FIG. 1 . Rangefinder  10  includes a telescopic monocular targeting sight  14  having an objective  16  and an eyepiece  18  supported in a common housing  20  along with a laser ranging system  22  and associated electronics. Laser ranging system  22  projects a laser beam (not shown) through a rangefinder lens  26 . Laser light reflected by a distant target (not shown) is then received by laser ranging system  22  through rangefinder lens  26  or another lens or receiver, and a lag time between the emission and reception of the laser light measured to determine a distance (range) from the rangefinder  10  to the target. This ranging technique is known to some as lidar. The actual methods employed by rangefinder  10  for determining the time between emission and reception of laser light and for calculating a line-of-sight range to the target may comprise any of a variety of methods. Rangefinder  10  may have an operating range from approximately three yards or less, to approximately 1,200 yards or more, depending on the reflectivity and size of the target, and possibly other factors.  
      Rangefinder  10  includes a power button  30  that is initially depressed to power up the rangefinder  10  and turn on the rangefinder&#39;s electronics, including a computer processor thereof. Power button  30  may thereafter be depressed and preferably held for a period of time (e.g., for one second or more) to turn off the electronics when desired. To help conserve battery power, an automatic timeout feature may also turn off the electronics after a period of inactivity, such as inactivity of more than 5 or 10 seconds. Rangefinder  10  may also include a menu interface  40  including a mode selector button  44  and a setting adjustment button  48 , which are further described below with reference to  FIGS. 2-4 . Skilled persons will appreciate that menu interface  40  may include more or fewer buttons, or controls of a different type, such as keypads, adjustment knobs, wheels, dials, touch screens, wired or wireless electronic interfaces, remote controls, and any other device through which a user can interface with and provide input to rangefinder  10 .  
       FIG. 2  depicts an electronic display  50  of rangefinder  10 , as viewed through eyepiece  18 . Electronic display  50  is superimposed on a field of view  51  of the targeting sight  14 , and includes a plurality of display elements  52  that may be individually controllable for display or blanking by one or more digital processor components of the electronics of rangefinder  10 . For purposes of illustration, all display elements  52 , including elements of a menu display  54 , a targeting display  56 , and a data display  58  are shown in  FIG. 2 .  
      In one embodiment, electronic display  50  comprises an LCD panel positioned in the optical path of targeting sight  14  between objective  16  and eyepiece  18 . The LCD panel includes normally-transmissive layers so that it does not obscure the field of view. For example, LCD panel may include transmissive electrodes formed of indium tin oxide (ITO). Display elements  52  may be reflective or opaque, or both, when active. A source of Illumination (not shown) may optionally be provided in targeting sight  14  for illuminating active display elements  52  to enhance their visibility in low ambient light conditions. The illumination source may be integrated in targeting sight  14  in such a manner so as to prevent illumination from being projected out of objective  16  toward a target. In other embodiments (not shown), electronic display  50  may comprise any of a variety of electronic display devices other than or in addition to an LCD display. For example, electronic display  50  may comprise fiber optic displays, light emitting diodes (LEDs), organic light emitting diodes (OLEDs), and others. Moreover, the display device need not be located in the optical path. For example, a display device such as an LCD, DLP, or another display device outside of the optical path may project an image of the menu, reticle, and data displays  54 ,  56 ,  58  onto a prism or reversed beam splitter located in the optical path.  
     Rotary Menu Display  
      With reference to  FIG. 2 , menu display  54  includes a plurality of menu icons  62  distributed along a perimeter  64  or periphery of the field of view  51 . Some or all of menu icons  62  may touch, abut, or overlap the perimeter or periphery of the field of view  51 , or may be radially adjacent the perimeter. The perimeter  64  may be defined by the outer limits of the targeting sight  14 , such as the boundaries of an exit pupil of the optical system of targeting sight  14 , or by the edges of a targeting display screen. Adjacent menu icons  62  may touch or be spaced apart along the periphery or perimeter  64 . The field of view  51  and the perimeter  64  may be circular, as shown in  FIGS. 2-5 , or may be of another shape, such as rectangular or square. Similarly, the menu icons  62  may be generally arranged in the shape of a circle, arc, rectangle, square, or another shape defined by perimeter  64 .  
      Menu icons  62  may comprise graphical icons, text displays, or combined text and graphical icons as shown in  FIG. 2 . Each of the menu icons  62  preferably identifies an adjustable feature of the rangefinder. For example, one or more of the following menu icons  62  and corresponding adjustable features may be included:  
                                                   Icon Label(s)   Feature Description                          &gt;150   Long range mode - ignores objects (brush,               etc.) closer than 150 yards           RAIN   Rain mode - filters out effects of rain           1 st  TGT   Measures range to closest target           LAST TGT   Measures range to furthest target           M - FT - YD   Units of range measurement(s)           LOS   Displays line-of-sight range           ° F. - ° C.   Temperature display mode and units           COMPASS   Compass mode - displays compass heading           DEC   Declination adjustment for compass mode           TBR   Displays TRUE BALLISTIC RANGE ™               (equivalent horizontal range for holdover               adjustment during incline shooting)           BOW   Bow hunting mode - affects TBR calculations           A - B - C   Ballistic group - affects TBR calculations                      
 
 Some of the features, such as long range mode (&gt;150), rain mode (RAIN), and others, may be adjustable only in that they can be toggled on and off (enabled and disabled). Others of the features, such as the units of range measurement (M-FT-YD), temperature display units (° F-° C), and ballistic groupings (A-B-C) MAY PROVIDE for selection of one of several possible mutually-exclusive predefined settings, which are defined by corresponding icons  62   a ,  62   b , and  62   c  each of which comprises multiple adjacent display segments  64 ,  66 , and  68  indicating the possible settings. Still other features, such as declination (DEC), may involve adjustment of a numerical setting or other value. For yet other features, a different sort of adjustment or input is required. For example, one menu feature may be a compass calibration mode, in which rangefinder  10  must be placed on a level surface and rotated in the horizontal plane for two full rotations (720 degrees). Many other features, functions, and labels are possible, and the above list should not be construed as limiting the kinds of adjustable features, icons, labels, values, and functions in an optical device according to the present disclosure. In alternative embodiments (not shown), different labels and icons may be used to identify the same or similar functions, and the above labels may be used to identify different functions. 
 
      Rangefinder  10  may also include features and capabilities found in other handheld or portable electronic devices. For example, rangefinder  10  may include a GPS sensor (not shown) that determines geographic location of the rangefinder  10  based on GPS satellite signals. GPS location data may be utilized by rangefinder  10  in combination with laser range measurements and compass headings to calculate a geographic position of a distant target, for example.  
      A method of operation of menu display  54  will now be described with reference to  FIGS. 2-4 . As shown in  FIG. 2 , all menu elements  62  of menu display  54  may be briefly displayed simultaneously upon activating a menu mode for adjusting feature settings of rangefinder  10 . Simultaneously displaying all menu display elements  62  (the “full menu”) allows the user to preview all of the available feature settings that can be selectively activated, deactivated, or adjusted in the menu mode, described below. This full menu display may also conveniently occur automatically upon powering up rangefinder  10  and before commencing a laser ranging operation. Alternatively, the full menu may be activated upon initially entering the menu mode.  
      In some embodiments, the benefit of previewing to the user the features available for adjustment in menu mode can be achieved without simultaneously activating all display elements  52  of electronic display  50  or all menu elements  62  of menu display  54 . For example, one or more segments  64 ,  66 ,  68  of a multi-segment icon  62   a ,  62   b ,  62   c  may be omitted from a full menu display, especially such segments  64 ,  66 ,  68  which do not correspond to a current setting. By way of further example, adjustable features that only affect selectable features (such as BOW and A-B-C, which only affect TBR, and DEC, which only affects COMPASS) might not be displayed when the primary feature is not currently active. Moreover, a full menu display may or may not involve display of all elements of targeting display  56  and data display  58 . For example, during a full menu display, targeting display  56  and data display  58  may be blanked or left unchanged.  
      To enter the menu mode, the user may manually depress mode selector button  44  or may otherwise input a menu activation command. After briefly displaying the full menu upon entering the menu mode (e.g., for 0.5 second to several seconds), a first one of the menu icons is then displayed to indicate that a first one of the features of rangefinder  10  is concurrently selected for adjustment. For example, as shown in  FIG. 3 , a first icon  80  (&gt;150) located at the top center of the field of view (12 o&#39;clock) may be displayed immediately following the full menu display to indicate that the first feature (the long range mode) is selected for adjustment (i.e. for toggling on or off). First icon  80  may be displayed alone, with other menu icons  62  being blanked or otherwise deactivated, as shown in  FIG. 3 . Alternatively, first icon  80  may be displayed by intermittently flashing or blinking first icon  80 , with the remaining menu icons  62  either displayed or blanked. Other modes of displaying or highlighting the first icon  80  may also be employed to signify that the first feature is selected for adjustment. For example, a color, size, or shape of first icon  80  can be changed to emphasize its display. Alternatively, the other (unselected) menu icons can be deemphasized or distinguished from first icon  80  by dimming, coloring, or reducing the size or shape of the unselected menu icons. The setting of the first feature may then be adjusted, or the user may merely leave the first feature setting unchanged and increment through the display menu  54  in a clockwise or counterclockwise manner to select a different feature from the display menu  54  for adjustment.  
      To adjust the setting of the first feature or any other selected feature, the user may enter a setting adjustment command by depressing setting adjustment button  48 , or by some other means, such as an adjustment wheel. In some embodiments, depressing setting adjustment button  48  adjusts the feature setting by toggling it on or off and immediately exiting the menu mode. In other embodiments, depressing setting adjustment button  48  toggles or adjusts the setting of the feature without exiting the menu mode. The original setting or a current setting of the feature, or both, may be displayed in the electronic display  50 , for example in data display  58  (as illustrated by the word “Off” in  FIG. 3 ), in menu display  54 , or by some other means of user feedback. In some embodiments, a current setting of the selected feature may be displayed dynamically during its adjustment. A dynamic display of a selected feature&#39;s current setting may be particularly useful for facilitating user adjustment of functions having a variable set point, such as declination (DEC), for example.  
      If a selected menu icon includes multiple adjacent segments indicating different possible settings of the selected feature, then the segment corresponding to a current setting of the selected feature may be displayed or flashed. For example, if the menu icon  62   a  corresponding to the unit of measurement display feature is selected, then one of the segments thereof  64  may be displayed. Alternatively, both the segment corresponding to the original setting and the segment corresponding to the currently adjusted setting may be displayed, with the segment corresponding to the currently adjusted setting preferably being highlighted in some manner, such as by intermittent flashing. The current setting can be adjusted by incrementing through the adjacent segments (e.g. 66), for example by depressing the mode selector button  44  one or more times.  
      To accept and store an adjusted setting, an accept command may be entered by the user. An accept command may be input by a dedicated acceptance button (not shown) of menu interface  40 , or by some other method such as depressing the setting adjustment button  48  then incrementing through the display menu  54  by depressing mode selector button  44 , or by some other input or sequence of inputs. Upon acceptance, the adjusted setting is saved, preferably in a computer-readable memory of the electronics of rangefinder  10  or some other associated memory device.  
      The user may enter mode selection commands to increment through the icons  62  of display menu  54 , for example by depressing the mode selector button  44  once for each menu icon  62 . Other methods of incrementing or providing a mode selection command may also be employed. The user may increment through the icons  62  of menu display  54  until a selected icon different from the first icon  80  is displayed or highlighted to indicate that a selected feature corresponding to the selected icon is then currently selected for adjustment. Thereafter the selected feature can be adjusted in the same or similar manner as the first feature, as described above.  
      If a period of inactivity occurs during menu navigation, the menu mode may time-out, which may cause the rangefinder  10  to revert to a ready mode (ready to range a target) or may cause the electronics of rangefinder  10  to be powered down. If the menu mode times out, then any adjustments made to feature settings may be saved. A user may manually exit the menu mode by depressing the power button  30  or depressing and holding one of the menu interface buttons  44 ,  48 .  
      The arrangement of icons  62  along the periphery or perimeter  64  of the field of view  51  may provide an intuitive user interface that facilitates operation of display menu  54 . Conveniently, the menu of rangefinder  10  may be only one level deep, thereby avoiding the complex and confusing menu hierarchies of many prior art aimed optical devices. To further improve the ease and speed of use of display menu  54 , first icon  80  preferably corresponds to a feature of rangefinder  10  that is expected to be most often adjusted by users. The second icon in the incremental (clockwise or counterclockwise) rotation of the menu selection is preferably the second most often adjusted feature, the third icon is preferably the third most often adjusted, and so-on. In the embodiment shown, the first icon  80  corresponds to the long range mode feature (&gt;150), the second is for the rain mode (RAIN), etc. Skilled persons will appreciate that the particular ordering of icons  62  around the periphery and sequence of features in the menu is a matter of preference and subject to difference of opinion.  
      Arrangement of icons  62  along the periphery may also help keep the important central region of the field of view  51  free of confusing and distracting icons or other information that could detract from a user&#39;s ability to acquire a target and aim the rangefinder  10 . In one embodiment, clutter is reduced in electronic display  50  by displaying only those menu icons  62  critical for proper use of rangefinder  10  or understanding of measurement readouts. At the same time, menu icons for disabled features and any menu icons for active features or settings that are non-critical or for which a user would easily remember their setting, such as the unit of measurement display, can be removed from the display without consequence. One example of selective display of menu icons during ranging is shown in  FIG. 5 . With reference to  FIG. 5 , data display  58  reads out a TRUE BALLISTIC RANGE™ of 518.5 yards, a line-of-sight range of 540 yards, and an angle of inclination of 160° to a target  86  viewed through targeting sight  14 . The menu icons  62  for TBR and LOS are displayed to distinguish the two different items of range information that are simultaneously displayed in data display  58 . Data display  58  may also include a battery charge indicator  88 .  
     Display Clearing Mode  
      To further reduce clutter in the field of view  51  and facilitate target acquisition, an optional display clearing mode may be included in rangefinder  10 . The clear display mode is illustrated by  FIG. 4  in which all menu icons  62  and other elements of electronic display  50  other than a reticle  90  of targeting display  56  are removed without turning off the functions themselves. Although  FIG. 4  shows only reticle  90  remaining, in alternative embodiments a limited subset of the elements of menu display  54  or data display  58  may remain displayed in the display clearing mode. In still other embodiments, the display clearing mode may clear all display elements  52 , including reticle  90 . The display clearing mode may be activated by depressing one or more buttons of rangefinder  10 . For instance, in one embodiment, from the ready mode, the setting adjustment button may be depressed and held for more than 1 second to activate the display clearing mode.  
     Selectable Reticles  
      To facilitate aiming at different distances and at different sizes and kinds of targets, reticle  90  may be selected from a variety of different possible reticle configurations shown in  FIGS. 6A  to  6 M. With reference to  FIGS. 2 and 6 A to  6 M, targeting display  56  may include various reticle elements or segments  92 , such as radiating posts  94 , opposing angle brackets  96 , curved brackets  98 , and centered crosshairs or PLUS POINT™ 100, for example. Reticles of  FIGS. 6A  to  6 M may be formed by turning on and off various ones or groups of reticle segments  92 . For example, a German #4 reticle of  FIG. 6M  can be formed by turning on the horizontal posts and the lower vertical post, but leaving the upper vertical post turned off.  
      The PLUS POINT 100, which may be used alone or with other reticle segments  92 , provides a very fine reticle that may be useful with or without other heavier reticle segments  92 , for aiming at varmints and other small targets. PLUS POINT 100 includes a proprietary open center that is approximately the width and height of the lines thereof, and in the shape of a square. The open center of PLUS POINT 100 avoids obscuring very small or very distant targets, while facilitating aiming of rangefinder  10 . Heavier curved brackets  96  and posts  94  may facilitate aiming in low light conditions, with or without PLUS POINT 100.  
      Thus, the targeting display  56  includes individually controllable reticle segments  92  and groups of reticle segments or elements that can be selectively activated and deactivated by a user to create various reticles ( FIGS. 6A-6M  and others), which may include symmetrical reticles, asymmetrical reticles, different sizes of reticles, heavy-post reticles, fine-line reticles, and customizable reticles. The number and variety of reticle configurations is limited only by the number of different reticle segments  92  included in targeting display  56 . For example, in the embodiment shown, thirteen reticle segments  92  are used to form the thirteen different reticle configurations of  FIGS. 6A-6M , although clearly many more variations would be possible using the same elements. Thus, a relatively small number of reticle segments can be employed to form a much larger number of possible reticle configurations.  
      In some embodiments, a BRACKET CIRCLE™ formed by four curved brackets  98  (as shown in  FIGS. 6C, 6D ,  61  and  6 J) may be sized to bracket a deer at 50 yards. Similarly, all four angle brackets  96  may be displayed to form a BRACKET SQUARE™ (as in  FIGS. 6E, 6F ,  6 G, and  6 H), sized to bracket an average elk torso at 40 yards or a deer torso at 30 yards. When combined with posts  94 , the BRACKET CIRCLE becomes a BRACKET CIRCLE DUPLEX™ (as shown in  FIGS. 6D and 6C ), and the BRACKET SQUARE becomes a BRACKET SQUARE DUPLEX™ (as shown in  FIGS. 6E and 6F ). Targeting sight  14  may include an optical system with 8× magnification and the brackets may therefore be sized for use at the magnification of the optical system. Thus, bracketing capabilities of certain ones of the reticles provide an intuitive mode of rough optical range estimating without laser ranging, in a manner familiar to hunters experienced in using Leupold DUPLEX™ reticles, mil-dot reticles, and other range-estimating riflescope reticles.  
      The various reticle configurations may be selected or reticles customized as part of the menu mode or in another setup process. In one embodiment, after rotating through all menu icons  62  in menu mode (i.e. after the A-B-C icon  62   c ), a reticle selection sequence commences in which a user may step through a display of the various reticles ( FIGS. 6A-6M ) for selection/approval. The user may increment through the various reticle options by continuing to depress the mode selector button  44 , as if an extension of the menu mode. When the desired reticle configuration is displayed, it can be selected and set by depressing the setting selector button  48 .  
      After turning on rangefinder  10  and optionally adjusting feature settings, reticle configuration, calibration, and display clearing mode, rangefinder  10  may be utilized to determine the range to a target. After aiming rangefinder  10  at a target using targeting sight  14 , the power button  30  is depressed to trigger emission of a laser pulse from laser ranging system  22  and to measure a range to the target  86  ( FIG. 5 ). For purposes of aiming rangefinder  10 , reticle  90  is preferably centrally located in the field of view  51  in relatively accurate alignment with the laser beam generated by the laser ranging system  22 , so that the laser beam is directed at the central aiming point of reticle  90  (i.e. at the center of the PLUS POINT™ 100 or other reticle elements). The alignment of targeting sight  14  and targeting display  56  relative to laser ranging system  22  may be preset at the factory or may be adjustable by the user, either mechanically or electronically.  
     CONCLUSION  
      Although the selectable reticles and other aspects of electronic display  50 , menu display  54 , targeting display  56  and data readout  58  are described herein in the context of a rangefinder  10 , they may also be readily employed in other kinds of aimed optical devices, such as riflescopes, spotting scopes, telescopes, cameras (digital and film), and video cameras, for example. Moreover, aimed optical devices according to certain embodiments may include monocular optical systems, binocular optical systems, bi-ocular optical systems, telescopes, riflescopes, and others, with or without magnification.  
      It will be obvious to those having skill in the art that many changes may be made to the details of the above-described embodiments without departing from the underlying principles thereof. The scope of the present invention should, therefore, be determined only by the following claims.