Patent Publication Number: US-8981650-B2

Title: Lighting device controller programming

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Patent Application No. 61/524,730 filed Aug. 17, 2011 which is hereby incorporated by reference in its entirety. 
    
    
     BACKGROUND 
     1. Technical Field 
     This application relates to lighting devices and, more particularly, to the programming of a controller within a lighting device. 
     2. Related Art 
     Flashlights and other types of lighting devices (e.g., headlamps or others) using light emitting diodes (LEDs) are rapidly replacing conventional sources of illumination such as incandescent bulbs. LEDs are significantly more efficient than incandescent bulbs and thus offer greater illumination power and battery life. Moreover, LEDs are typically less fragile and are thus more robust than incandescent bulbs. The incorporation of LEDs has not been the only major recent technological advance in the lighting device arts. For example, LED-based lighting devices may now include a controller such as a microcontroller or a microprocessor. 
     The addition of a controller enables the lighting device to be programmed to regulate the power supplied to the LED as a function of a switch actuation from the user as well as the battery condition. Moreover, the microcontroller provides various modes of operation. For example, a lighting device may include an SOS mode, a power-saving mode, or other modes. Indeed, the nature of the operating modes is only limited by the programmer&#39;s ingenuity. Although the addition of a microcontroller thus enhances lighting device&#39;s operation, a user typically has no means of re-programming the microcontroller to customize the lighting device to their particular needs. In that regard, the addition of a suitable input programming port such as a universal serial bus (USB) port to provide programming access to the microcontroller would add additional expense. 
     Accordingly, there is a need in the art for providing improved lighting device programming access. 
     SUMMARY 
     In accordance with a first embodiment, a lighting device is provided that includes an LED; and a controller configured to receive a programming signal generated by the LED in response to illumination of the LED with an externally-supplied light signal modulated with the programming signal. 
     In accordance with a second embodiment, a method is provided that includes: illuminating a lighting device&#39;s LED with a light signal modulated with a programming signal, wherein the LED generates a current responsive to the illumination; and programming a controller within the lighting device according to the programming signal received from the illuminated LED. 
     In accordance with a third embodiment, a lighting device programming tool is provided that includes a housing adapted to mate with a lighting device bezel; at least one LED contained within the housing; and a driving circuit operable to drive the LED according to a programming signal supplied by a programming host. 
     The scope of the invention is defined by the claims, which are incorporated into this section by reference. A more complete understanding of embodiments of the present disclosure will be afforded to those skilled in the art, as well as a realization of additional advantages thereof, by a consideration of the following detailed description of one or more embodiments. Reference will be made to the appended sheets of drawings that will first be described briefly. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG. 1  is a longitudinal cross sectional view of a flashlight and an external programming tool in accordance with an embodiment of the disclosure. 
         FIG. 2  illustrates an alternative embodiment for the programming tool of  FIG. 1 . 
         FIG. 3  is a longitudinal cross sectional view of a programmable flashlight having selectable levels of power output in accordance with an embodiment of the disclosure. 
         FIG. 4  is a cross-sectional view of the rear leaf spring switch for the flashlight of  FIG. 3  in accordance with an embodiment of the disclosure. 
         FIG. 5  is an exploded view of a programmable flashlight including selectable light sources in accordance with an embodiment of the disclosure. 
         FIG. 6A  shows a first selection of a light source by the flashlight of  FIG. 5  in accordance with an embodiment of the disclosure. 
         FIG. 6B  shows a second selection of a light source by the flashlight of  FIG. 5  in accordance with an embodiment of the disclosure. 
     
    
    
     Embodiments of the present disclosure and their advantages are best understood by referring to the detailed description that follows. It should be appreciated that like reference numerals are used to identify like elements illustrated in one or more of the figures. 
     DETAILED DESCRIPTION 
     A lighting device programming technique is disclosed herein that obviates the need to reconfigure a lighting device with a programming input port such as a USB port. The lighting device is configured to respond to programming through its LED(s) rather than through an external programming input port. Although various embodiments will be described and illustrated with regard to various flashlights, the techniques so described and illustrated may also be applied to other embodiments and other types of lighting devices such as, for example, headlamps, portable lighting devices, and other lighting devices. 
     Turning now to the drawings,  FIG. 1  illustrates an example flashlight  100 . A battery  105  powers at least one LED  110  through a driver circuit  115  as controlled by a microcontroller or processor  120 . Depending upon the applied programming, microcontroller  120  controls switches and signal conditioning circuitry within driver circuit  115  to, for example, control the amount of power supplied to LED  110  responsive to a user&#39;s power mode selection through input controls  125 . 
     Flashlight  100  may be configured into a normal mode of operation and also a programming mode of operation through appropriate actuation of input controls  125 . In the programming mode, LED  110  responds to an externally-supplied light signal  130  (also referred to as light  130 ) supplied by an external programming tool  135 . Light  130  may be implemented in accordance with any desired non-visible and/or visible wavelengths as may be desired in various applications. For example, in one embodiment, light  130  may be infrared light. In another embodiment, light  130  may be visible light. 
     Programming tool  135  includes at least one LED  140  powered through a driver circuit  145  as controlled by a programming microcontroller or processor  150 . LED  140  is thus driven according to a programming signal generated so that light  130  is modulated by the desired programming signal. For example, the programming signal may simply be an on-off keying of light  130  although any suitable modulation scheme may be used to modulate light  130 . In response to the illumination by light  130 , LED  110  will generate a current or voltage sensed by microcontroller  120 . The generated current or voltage is demodulated and digitized in driver circuit  115  to recover a digital programming signal that was originally applied by programming tool  135  to modulate light  130 . In the programming mode, microcontroller  120  responds to the programming signal so as to be programmed into the desired behavior. 
     A user could thus use programming tool  135  to program microcontroller  120  to effect a desired mode of operation. For example, an SOS light pattern could thus be programmed into flashlight  100  using programming tool  135 . Alternatively, microcontroller  120  could be programmed so that a user could select different LED sources and/or power levels through actuations of input controls  125 . Advantageously, flashlight  100  thus needs no external programming port, which dramatically lowers costs yet enables programming of microcontroller  120 . 
     Processor  150  need not be included within programming tool  135 . For example, as seen in  FIG. 2 , a programming dongle  200  includes LED  140  and LED driver circuit  145 . A power source for programming tool  135  is not shown for illustration clarity in both  FIGS. 1 and 2 . Dongle  200  is designed to be placed directly against the bezel of flashlight  100  so as to better illuminate LED  110 . A programming host such as a personal computer (PC)  210  delivers a programming signal over a bus such as a USB cable  215  so that LED  140  is driven accordingly to program flashlight  100  as desired. Note that LED  140  may also respond to illumination from flashlight  100  so that an error-free reception of the programming signal may be confirmed (e.g., to indicate successful or unsuccessful programming). Thus, light  130  is shown not only propagating from programming tool  135  but also being received by programming tool  135 . Driver circuit  145  may include demodulating and analog-to-digital conversion circuitry to retrieve a digital confirmation signal from flashlight  100  so that host PC  210  is assured that the desired programming signal has been received correctly. In various embodiments, light  130  propagating from flashlight  100  to programming tool  135  or programming dongle  200  may be used to provide other information from flashlight  100 , such as data corresponding to programmed configurations of microprocessor  120  or other components of flashlight  100  for storage and subsequent retrieval by microprocessor  150  or PC  210 . 
     As discussed previously, the flashlight programming through LED illumination may effect a wide variety of flashlight behaviors. For example,  FIG. 3  shows a flashlight  300  in which input controls  125  of  FIG. 1  comprise a rear leaf spring switch  322  and a programming mode switch  320 . Driver circuit  115  is not shown for illustration clarity. A normal mode of operation versus the programming mode of operation are selected by a cycling of programming mode switch  320 . In other words, an initial actuation of switch  320  may select the normal mode of operation. A successive actuation of switch  320  may then select the programming mode. An additional actuation of switch  320  would then select normal mode operation, and so on. Microcontroller  120  may be configured to flash LED  110  to confirm to the user that the flashlight has entered the programming mode. 
     The resulting programming of microcontroller  120  controls the response of microcontroller  120  to actuation of leaf spring switch  322  during the normal mode of operation. Switch  322  is contained within a tail cap  332  having an elastomeric flexible dome  334  covering a switch actuator  336 . Switch  322  has a movable portion  340  having several contacts  342  each connected to a housing ground formed by a conducting flashlight housing  324 . Movable portion  340  reciprocates axially with respect to a fixed switch portion  344  connected to a conductive sleeve  326 . Conductive sleeve  326  connects to a negative contact of batteries  105 . A positive contact of batteries  105  couples to microcontroller  120 . 
     As shown in  FIG. 4 , contacts  342  of movable portion  340  may comprise leaf springs, each extending a different distance from a base panel that is connected to the housing ground. Switch  322  of  FIGS. 3 and 4  is illustrated in a simplified form for clarity of the principles of its operation. For example, switch  322  may be configured to allow a bi-level operation with contacts  342  arranged in arcs or annuluses to allow the switch to function when the tail cap  332  is rotated through a range of positions. 
     In one embodiment, all the leaf spring contacts  342  are connected to each other. As the switch  322  is depressed over its range of axial travel, the contacts  342  contact fixed element  344  in sequence. As discussed further in U.S. Pat. No. 7,722,209, the contents of which are hereby incorporated by reference in their entirety, fixed element  344  may include an array of pads  346  each positioned to be contacted by a respective end of a leaf spring contact  342 . The pads  346  are all connected to a central node that connects via a plated through-hole or other means to the opposite side of fixed element  344 , which thereby connects to conductive battery sleeve  326 . Each pad  346  connects to the central node with a different intervening resistance 
     Before the switch  322  is depressed, the resistance between fixed portion  344  and movable portion  340  is infinite. When the switch  322  is slightly depressed, a first leaf spring contact  342  makes contact with a pad  346  associated with a resistor. Microcontroller  120  may thus determine by this resistance that switch  322  has been pressed to an intermediate position. Microcontroller  120  may be programmed during the programming mode to respond to such an intermediate switch actuation with a driving of LED  110  with some desired level of power for example, the intermediate switch actuation may produce an intermediate powering of LED  110 . 
     When elastomeric dome  334  is further depressed, another leaf spring contact  342  makes contact with a pad  346 . In the simplest case, the switch  322  has only two contacts  342  (not the four illustrated), and the second contact  342  would contact a pad  346  having no resistor. This reflects a condition when the switch  322  is fully depressed, and, depending upon the applied programming, could cause microcontroller  120  to provide full brightness illumination. In the more complex embodiment illustrated, there are five switch actuation states for switch  322  (including the released condition) that may be sensed by microcontroller  120 . Depending upon the applied programming, various brightness levels or preselected dimmed or hue outputs might be provided based on the actuation state. 
     The programming ability for microcontroller  120  provides significant additional capabilities. For example, microcontroller  120  may detect the duration of pressure on the switch  322 , the magnitude of pressure, and the number and pattern of actuations (e.g., enabling distinguishing of commands in the manner of a single or multiple click computer mouse.) In one embodiment, some users will prefer programming that avoids accidental maximum illumination (e.g., such as for infantry troops operating at night), while other applications such as police work will prefer ready access to maximum illumination without delay or difficulty. 
     The programmability of microcontroller  120  may be advantageously combined with an ability for a user to select from multiple light sources as described in U.S. patent application Ser. No. 12/702,146, filed Feb. 8, 2010, the contents of which are hereby incorporated by reference in their entirety. An example flashlight  500  is shown in exploded view in  FIG. 5 . A rotatable bezel  501  mechanically connects to a lens assembly formed from a planar lens  503  and a total internal reflection (TIR) lens  504 . As seen in  FIGS. 6A and 6B , TIR lens  504  is configured to have an optical source inlet  602  that is offset from a central longitudinal axis  600  for flashlight  500 . Accordingly, in one embodiment, rotation of bezel  501  may result in off center rotation of bezel  501 , as well as of components attached to bezel  501 , such as TIR lens  504 . A printed circuit board  550  includes several LEDs. For example, board  550  may include a white light LED  604  and an infrared LED  603 . Depending upon the rotation of bezel  501 , optical source inlet  602  will select from one of the available light sources. For example, if the bezel  501  is rotated as indicated by direction  610  of  FIG. 6A , white light LED  604  is selected. Conversely, if bezel  501  is rotated as indicated by direction  611  of  FIG. 6B , infrared LED source  603  is selected. A housing  560  for flashlight  500  includes the remaining components discussed with regard to flashlight  100 . In one embodiment, flashlight  500  may include the rear leaf spring switch  322  and the programming mode control switch  320  discussed with regard to  FIGS. 3 and 4 . Microcontroller  120  may be configured to respond to a programming signal from just one of the multiple light sources. Alternatively, microcontroller may be configured to respond to a subset of the light sources or all of the light sources with respect to programming. 
     Bezel  501  is configured to engage stops such that it may be “clicked” through various selections of light sources as it is rotated with respect to housing  560 . Microcontroller  120  may sense the selection of a light source through rotation of bezel  501  through appropriate sensors such as Hall sensors. By programming microcontroller  120  as discussed with regard to  FIGS. 1 and 2 , a user may program the desired brightness of selected light sources or hues. The ability of programming microcontroller  120  to record and store sequences of different durations also permits the storage of messages (e.g., such as entered by Morse code) and subsequent transmission in a regulated format that is readily receivable by other electronic devices. With the fast response time of LED lamps relative to incandescent, such messages may be “hidden” during flashlight operation (e.g., in visible or infrared wavelengths) as brief, possibly imperceptible variations of the output level. 
     Embodiments described above illustrate but do not limit the invention. Thus, it should also be understood that numerous modifications and variations are possible in accordance with the principles of the present invention. Accordingly, the scope of the invention is defined only by the following claims.