Abstract:
Systems, devices, and methods for a decorative outdoor light fixture that can include an adjustable motion sensor with a rectangular coverage pattern. An adjustable motion sensor for a light fixture can include an outer housing connected to a light fixture frame, a movable sensor assembly including a motion detector contained within the outer housing, a lens covering a portion of the outer housing in the path of the motion detector sensing beams to direct the sensing beams in a rectangular coverage pattern, and a sensor adjustment mechanism accessible from an exterior of the outer housing to allow a user to rotate the sensor adjustment mechanism to cause the motion detector to move upward and downward. The adjustable motion sensor covered with a fixed window that hides the motion sensor assembly from view.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This invention claims the benefit of priority to U.S. Provisional Application Ser. No. 61/945,528 filed on Feb. 27, 2014, the entire disclosure of which is incorporated by reference in its&#39; entirety. 
    
    
     FIELD OF INVENTION 
     This invention relates to light fixtures, and in particular to systems, devices, and methods for a decorative outdoor light fixture that includes an adjustable motion sensor with a rectangular coverage pattern. 
     BACKGROUND AND PRIOR ART 
     Motion sensing controlled lighting and decorative outdoor light fixtures are very popular. Often customers would like to have a product which is decorative, but which also incorporates automatic motion sensing control. A number of problems arise when integrating a motion sensing feature into the light fixture. 
     From a sensing perspective, the ideal solution is a sensor head which can be readily positioned and aimed so that the sensed coverage area is precisely where it is desired. Unfortunately a movable sensor head is not aesthetically pleasing on a decorative fixture; consequently the desired approach requires a motion sensor that can be concealed within a portion of the light fixture. 
     In order to achieve a concealed approach, a fixed sensor is often used which can unfortunately result in many compromises in sensor performance. The biggest compromise is that the sensor has no mechanical adjustment and therefore the coverage pattern is fixed. This is ultimately a compromise in terms of the coverage area. Using traditional lens design approaches, the coverage pattern is an approximate fan shape. However, most areas where the coverage is needed such as a yard are not shaped like a fan. As such, it would be more desirable to have a rectangular coverage pattern. 
     Furthermore, a large problem with a fixed coverage pattern are the false activations that can occur. In a typical application, the house on which the fixture is mounted can be some 40 feet from a street. Although the stated coverage range may typically be 30 feet, under some environmental conditions, such as a passing car that is at a substantially different temperature than the ambient temperature, the sensor may be able to detect the car at ranges far beyond the 30 foot stated range of the sensor. This result can cause undesirable false activation when cars pass by. In short front yards, the street may be readily within the range of the sensing area virtually all of the time, causing continual false activation. 
     False activations can be reduced by reducing sensitivity in motions sensors that have sensitivity adjustment capability. However, sensitivity adjustments can unfortunately further reduce the sensitivity to motion of people, which may be undesirable. 
     Thus, the need exists for solutions to the above problems with the prior art. The systems, devices, and methods of the present invention solve some complicated mechanical problems within a small space to deliver a mechanism that allows the internal sensor to be tipped to adjust the pattern of coverage, especially the maximum distance at which it can sense motion, because the sensing beams can be angled to strike the ground thus preventing the coverage pattern from extending beyond the target area. 
     SUMMARY OF THE INVENTION 
     A primary objective of the present invention is to provide systems, devices, and methods for an aesthetically decorative light fixture with an adjustable motion detector. 
     A secondary objective of the present invention is to provide systems, devices, and methods for a light fixture with an adjustable motion detector that tilts an internal sensor upward and downward for changing the pattern of coverage. 
     A third objective of the present invention is to provide systems, devices, and methods for a light fixture with an adjustable motion detector with coverage that forms a rectangular shaped pattern of coverage. 
     A fourth objective of the present invention is to provide systems, devices, and methods for a decorative light fixture with internal motion sensor and an external adjustment mechanism. 
     A first embodiment provides an adjustable motion sensor for a light fixture including a bracket mechanically installable within the light fixture, a movable sensor housing connectable with the bracket, a motion sensor connectable to the movable sensor housing, the motion sensor with an adjustable rectangular coverage area, an adjustment mechanism connected to move the movable sensor housing to adjust a position of the motion sensor housed within the movable sensor housing, and an electronic module in communication with the motion sensor and for supplying an electrical source to the motion sensor and controlling the operation of a lamp in the light fixture. 
     The bracket can be a C-shaped frame to route electrical wires between the light fixture lamp, the motion sensor and the electronic module and an attachment point for fixedly attaching the movable sensor housing to the C-shaped bracket, and can include at least two rods extending outward from the C-shaped bracket as the structural connection point between the lamp and the light fixture. The at least two rods can be hollow for routing the electrical wires through the hollow rods. The rods can be threaded at one end for mating engagement with a threaded aperture in the C-shaped bracket. 
     The motion sensor connectable to the movable sensor housing can include 
     a motion detector and a lens with a rectangular coverage area covering the motion detector to direct sensing beams from the motion detector to provide the rectangular coverage area. 
     The movable sensor housing can include a movable sensor pod that fits within the space formed by the movable sensor housing with the motion sensor connected within the movable sensor pod. 
     The adjustment mechanism can include a sensor adjustment drive rotatable to apply a force to move the movable sensor pod to adjust the position of the motion sensor housed within the movable sensor pod upward and downward and a head on an exterior end of the sensor adjustment drive accessible for a user to rotate the head to change the position of the motion sensor upward and downward. The adjustment mechanism can include a drive gear coupled with the sensor adjustment drive such that rotation of the sensor adjustment drive causes the movable sensor pod to move and change the direction that the motion sensor is being aimed at. 
     The electronic module in communication with the movable sensor can supply an electrical source to the motion sensor and can control the operation of a light source in the light fixture. 
     A second embodiment provides an adjustable motion sensor for a light fixture that includes an outer housing connected to a light fixture frame, a movable sensor assembly including a motion detector contained within the outer housing, a lens covering a portion of the outer housing in the path of the motion detector sensing beams, with the lens directing the sensing beams in a rectangular coverage pattern; and a sensor adjustment mechanism coupled with the movable sensor assembly. The sensor adjustment mechanism can be accessible from an exterior of the outer housing to allow a user to rotate the sensor adjustment mechanism to cause the motion detector to move upward and downward. 
     The movable sensor assembly can include a bracket mechanically installable within the light fixture frame above or below a lamp socket in the light fixture, the movable sensor assembly inserted into the bracket, a sensor housing assembly within the movable sensor assembly, and a sensor drive mechanism coupled with the movable sensor assembly. The sensor drive mechanism can be accessible from an exterior of the outer housing to allow a user to rotate the sensor drive mechanism to cause the motion detector to move upward and downward. 
     The bracket can be a C-shaped frame to route electrical wires between the lamp socket, the motion detector and an electronic module and can include an attachment point for fixedly attaching the movable sensor assembly to the C-shaped bracket; and can include at least two rods extending outward from the C-shaped bracket as the structural connection point between the lamp and the light fixture and the rods can be hollow for routing the electrical wires through the hollow rods. 
     The sensor housing can include a movable sensor pod that fits within the space formed by the sensor housing with the motion detector connected within the movable sensor pod. 
     The sensor adjustment mechanism can include a sensor adjustment drive shaft rotatable to apply a force to move the movable sensor assembly to adjust a horizontal position of the motion detector housed within the movable sensor assembly upward and downward and a head on an exterior end of the sensor adjustment drive shaft accessible for a user to rotate the head to change the horizontal position of the motion detector upward and downward. The sensor adjustment mechanism can include a drive gear coupled with the sensor adjustment drive such that rotation of the sensor adjustment drive causes the movable sensor assembly to change the direction the motion sensor is aiming, and can include a drive gear on the adjustment drive shaft and a rack gear on the sensor housing. 
     A third embodiment can include a light fixture with an adjustable motion sensor with a rectangular coverage area that includes a light fixture frame with an outer sensor housing located above or below a light socket within the light fixture frame, a bracket mechanically installable within the outer sensor housing, and a sensor housing connectable with the bracket, a movable motion sensor connectable to the sensor housing, a lens covering a portion of the outer housing in the path of the motion sensor sensing beams, with the lens directing the sensing beams in a rectangular coverage pattern. 
     A sensor adjustment mechanism can be coupled with the movable motion sensor, the sensor adjustment mechanism can be accessible from an exterior of the outer housing to allow a user to rotate the sensor adjustment mechanism to cause the movable motion sensor to move upward and downward. 
     The sensor adjustment mechanism can include a sensor adjustment drive shaft rotatable to apply a force to move the movable motion sensor to adjust a position of the motion sensor housed within the sensor housing upward and downward and a head on an exterior end of the sensor adjustment drive shaft accessible for a user to rotate the head to change the position of the motion sensor upward and downward, and an electronic module in communication with the motion sensor and a light socket for supplying an electrical source to the motion sensor and controlling the operation of a lamp in the light fixture lamp socket. 
     To the knowledge of the inventor, the design and function of the light fixture with an adjustable motion sensor with rectangular coverage pattern of the present invention has not been suggested, anticipated or rendered obvious by any of the prior art references. 
     Further objects and advantages of this invention will be apparent from the following detailed description of the presently preferred embodiments which are illustrated schematically in the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG. 1  is a side view of a decorative light fixture showing fixed motion detector window and sensor adjustment drive. 
         FIG. 2  is a side view (ghosted) of light fixture showing placement of “C” bracket that houses the adjustable sensor pod. 
         FIG. 3  is a perspective view of “C” bracket used in  FIG. 2 . 
         FIG. 4A  and  FIG. 4B  are side views, respectively, of the sensor pod used in the “C” bracket showing the movable sensor adjusted up and down. 
         FIG. 5  is a partial sectioned side view of the light fixture showing the sensor pod placement in the “C” bracket. 
         FIG. 6A  and  FIG. 6B  are rear sectioned views, respectively, of the sensor pod of  FIG. 4A  and  FIG. 4B  showing the movable sensor adjusted up and down. 
         FIG. 7A  and  FIG. 7B  are side perspective views of the sensor pod, respectively, with the movable sensor adjusted up and down. 
         FIG. 8  is a side sectional view of the sensor pod showing the light fixture and accessory wiring. 
         FIG. 9  is a chart showing lens detection for people with maximum sensitivity at maximum elevation. 
         FIG. 10  is a chart showing lens detection for warmer objects at maximum sensitivity and maximum elevation. 
         FIG. 11  is a chart showing lens detection for warmer objects at maximum sensitivity and elevation of approximately −3 degrees. 
         FIG. 12  is a chart showing lens detection for people with maximum sensitivity and an elevation of approximately −3 degrees. 
         FIG. 13  is a chart showing lens detection for warmer objects with sensitivity of approximately 70% and elevation of −3 degrees. 
         FIG. 14  is a chart showing lens detection for people with sensitivity of approximately 70% and an elevation of approximately −3 degrees. 
         FIG. 15  is a chart showing lens detection for people with sensitivity of approximately 20% and an elevation of approximately −10 degrees. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Before explaining the disclosed embodiments of the present invention in detail it is to be understood that the invention is not limited in its applications to the details of the particular arrangements shown since the invention is capable of other embodiments. Also, the terminology used herein is for the purpose of description and not of limitation. 
     In the Summary above and in the Detailed Description of Preferred Embodiments and in the accompanying drawings, reference is made to particular features (including method steps) of the invention. It is to be understood that the disclosure of the invention in this specification includes all possible combinations of such particular features. For example, where a particular feature is disclosed in the context of a particular aspect or embodiment of the invention, that feature can also be used, to the extent possible, in combination with and/or in the context of other particular aspects and embodiments of the invention, and in the invention generally. 
     In this section, some embodiments of the invention will be described more fully with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout, and prime notation is used to indicate similar elements in alternative embodiments. 
     A list of components will now be described.
       10  Decorative light fixture     15 . Outer housing     20  Fixed window     25  Sensor lens     30  ‘C” bracket     40  Threaded rod(s)     50  Sensor pod assembly     60  Movable sensor assembly     70  Sensor adjustment drive shaft     80  Drive pinion gear. Part of adjustment drive shaft     90  Fixture wiring     100  Accessory wiring     110  Adjustment drive shaft access hole in light fixture     120  Movable sensor housing     130  Adjustment rack gear. Part of movable sensor housing     140  Sensor housing pivot pin. This pin is captured in the sensor pod and is the axis for the sensor adjustment     150  Pivot axis   

     As stated above, motion sensing controlled lighting and decorative outdoor light fixtures are very popular. Often customers would like to have a product which is decorative, but which also incorporates automatic motion sensing control. A number of problems arise when integrating a motion sensing feature. From a sensing perspective, the ideal solution is a sensor head which can be readily positioned and aimed so that the sensed coverage area is precisely where it is desired. Unfortunately a movable sensor head is not aesthetically pleasing on a decorative fixture; consequently the approach requires a motion sensor that can be concealed within a portion of the light fixture. 
     The problems associated with motion sensing decorative lights can be solved by providing a hidden motion sensor with an adjustment mechanism that allows the sensor to be pointed downward over a variety of angles from horizontal. The way to achieve this solution is to provide a sensor assembly within sensor housing. 
       FIG. 1  is a side view of a decorative light fixture  10  showing the fixed optically transparent (at IR wavelengths) window  20  that conceals the internal motion sensor. The outer housing  15  and window  20  is fixed, but the inner sensor includes a means of pivoting the inner sensor so that it can be adjusted upward or more downward facing. The sensor lens  25  is designed with a rectangular coverage pattern instead of the fan-like coverage of the prior art fixtures. The decorative light fixture  10  of the present invention instead extends to provide a rectangular coverage pattern. In addition, the rectangular coverage pattern sensing beams have increased sensitivity that are aimed to provide coverage to the corners of the rectangle. 
     Fixed window  20  is an optically transparent (at IR wavelengths) window that conceals the internal motion sensor, C-bracket, etc. and also protects the internal structure from rain, snow, wind, etc. Fixed window  20  is attached to the front of sensor pod assembly  50 . Sensor pod assembly  50  holds the fixed window  20  against an opening in the front of  15  the lamp fixture housing. The color of fixed window  20  can be matched to the color of the lamp housing and must allow the passage of IR wavelengths with no significant reduction. Alternately, the fixed window  20  could be mounted directly to outer housing  15 . 
     The sensor lens  25  wraps around the front side of movable sensor assembly  60 . The sensor lens  25  moves with the movable sensor assembly  60  and can be designed such that the sensor lens  25  creates a rectangular pattern and moves up and down with movable sensor assembly  60 . 
     The decorative light fixture with adjustable motion sensing capability shown in  FIG. 1  differs from prior art and achieves a challenging aesthetic requirement, while providing an excellent rectangular coverage pattern that can be adjusted downward from horizontal, while still maintaining a rectangular coverage pattern. 
     As shown in  FIG. 2 , the decorative light fixture  10  with adjustable sensing coverage area includes a C-shaped sensor bracket  30  housed within the fixture base outer housing. Housing the adjustable sensing mechanism within the C-shaped bracket  30  solves complicated mechanical problems within a small space by allowing the internal sensor to be tipped to adjust the pattern of coverage. In particular, the sensing beams can be angled to strike the ground within the target area, so it is not possible for coverage to extend beyond the target area. 
     Referring to  FIG. 2  in conjunction with  FIG. 1 , the decorative light fixture  10  incorporates a motion sensor which is concealed behind the fixed window  20 . The motion sensor is contained within a C-shaped bracket  30  which has three threaded rods  40  as shown more clearly in  FIG. 3 . The threaded rods  40  provide the main structural connection point between the lamp and base of the light fixture  10 . The threaded rods  40  are also used as a pathway for routing wires which pass to the light bulb socket and the movable sensor  60  shown in  FIG. 4A . As shown in  FIGS. 2 and 3 , the rods can be hollow rods to allow the light bulb socket wires to pass through the upper rod  40  and be routed to the center rod into the wall mounting structure of the light fixture  10  as shown in  FIG. 8 . While the rods can be threaded for assembly, the rods can also be press fit into the apertures in the C-shaped bracket. 
       FIGS. 4A and 4B  are side views of the sensor pod showing the movable sensor adjusted upward and downward, respectively (fixed window  20  not shown). As shown, the sensor pod  50  fits within the space formed by the C-shaped bracket  30 . The sensor pod  50  has several major elements including a movable sensor  60  that engages with the sensor adjustment drive  70 . The sensor adjustment drive is rotated to apply forces to move the sensor  60  over a range between the upward direction shown in  FIG. 4A  and the downward direction shown in  FIG. 4B . The movement of the sensor assembly  60  is accomplished using a drive gear  80  coupled with the movable sensor assembly  60  causing the sensor assembly  60  to rotate to adjust the direction the sensor assembly  60  is aiming. 
     The sensor pod  50  includes a provision to route fixture wires  90  behind the movable sensor  60 .  FIG. 5  is a side view of a decorative light fixture  10  showing the placement of the sensor pod  50  within the C-shaped bracket.  FIG. 5  also illustrates how the C-shaped bracket  30  and rods  40  hold the sensor pod assembly  50  within the lamp housing. While the decorative light fixture shown has the lamp above the sensing assembly, other light fixture styles have the lamp below the sensor pod  50  without deviating from the scope of the present invention. Depending on the style of the decorative light fixture  10 , the lamp can be located above or below the sensor pod  50 , and thus follow a second alternate fixture wire  100  path as shown in  FIG. 8 . 
     The sensor pod assembly  50  can have a decorative fixed window  20  which is used to conceal a movable sensor assembly  60 . The decorative fixed window  20  can be critical to the design, because the hidden internal sensor pod assembly  50  would not be aesthetically pleasing if it were visible. The C-shaped bracket  30  allows the sensor pod assembly  50  to be located in a position with excellent visibility to the desired sensing area in the front and sides of the fixture  10 . The internal movable sensor  60  has a pivot point which allows it to tip downward from horizontal over a range of approximately 0 to approximately 25 degrees, which allows substantial control of the forward range of the sensing area. 
       FIG. 6A  is a rear sectioned view of the sensor pod showing the movable sensor  50  adjusted up ( FIG. 6A ) and down ( FIG. 6B ), the fixed window  20  and sensor lens  25  are not shown. The drive gears  80  on the adjustment drive shaft  70  and the rack gears  130  on the sensor housing are visible. The drive mechanism  70  can be operated using a handheld tool, such as a screw driver, and a critical element of the drive mechanism  70  can be a gear drive  80  arrangement that provides rotational motion in the same direction as sensor  50  such that the direction of rotation of the drive shaft  70  is intuitive to the user.  FIG. 7A  and  FIG. 7B  are side perspective views of the sensor pod of  FIGS. 6A and 6B , respectively, with the movable sensor adjusted up and down. 
     Referring to  FIGS. 6A and 6B , as the drive shaft shown in  FIG. 6A  is rotated clockwise, the sensor assembly  50  rotated in the same direction as shown by the hollow arrows in  FIG. 6B . Thus, as the sensor adjustment drive shaft  70  is rotated, the drive pinion gears  80  which is part of the drive shaft are rotated in turn moving the adjustment rack gear  130  that is part of the movable sensor housing  120 . The sensor housing pivot pin  140  is captured in the sensor pod and is the axis for the sensor adjustment. To provide space for fixture wires that also pass through the same space, the gear drive mechanism uses two gears  80  which are spaced apart to maximize wire space availability between the two gears  80 . The open spaces at the top and bottom of the sensor pod  50  also provide free access for wires to pass through. 
     The sensor lens  25  (not shown) that covers the movable sensor assembly  60  can be designed to provide a substantially rectangular coverage pattern. However larger heat sources such as passing cars can activate the sensor beyond the normal coverage area for people. The tipping (adjusting) feature allows the movable sensor assembly  60  to be angled downward so that rather than directing sensing beams straight outward, the sensing beams are directed to strike the ground at various distances depending on the level of adjustment. 
     As a result the sensor mechanism can be adjusted to eliminate false activations by passing cars since the passing cars are no longer within view of the sensing beams. 
       FIG. 8  is a side sectional view of the sensor pod  50  with the movable sensor  60  adjusted up. As previously described, depending on the light fixture type, the fixture electrical wires  90  can be routed to pass through the upper hollow rod  40  when the lamp is located above the sensor assembly  50  and through the opposite rod  40  when the lamp is located below the sensor assembly  50  as shown by the dashed lines  100 . 
     Still referring to  FIG. 8 , the assembly sequence of the sensor pod  50  can be very helpful because the fixture can be loosely prewired and the sensor pod  50  can be inserted to push the fixture wires to the back of the C-shaped bracket  30 . The sensor pod  50  includes two halves which captures the movable sensor  60  and the sensor adjustment drive  70  as the two halves are screwed together. The outer fixed window  20  on the sensor pod assembly  50  is then attached by sliding the lens tabs through the slots after the case halves are assembled. The threaded rods  40  can have hidden nuts which must be tightened to complete the final assembly of the fixture. 
     While an example of a sensor drive assembly can be configured for installation and use, those skilled in the art will appreciate that a variety of different configurations can be used to engage the sensor to the sensor adjustment drive. This includes a cam type action which lifts the adjustable sensor up and down. The sensor could also be mounted in a different fashion, not using the C-shaped bracket without deviating from the scope of the invention and still be installed in the area immediately below or above the lamp socket. 
     The present invention solves some serious problems that have plagued prior art motion sensing decorative lights, mainly adjustability of sensor coverage area. By hiding a movable sensor behind a fixed window, the sensor can be aimed downward to reduce or eliminate spurious false activation by cars on nearby streets while still preserving the aesthetic appearance of the fixture. Because the decorative light fixtures are typically mounted on the front of a home, in a majority of applications, they are pointed directly toward the street with potential sources of false triggering under the right conditions. The ability to point the sensor downward means that the coverage can be set differently based on the distance between the sensor and the street so that it does not direct beams directly into the street. 
     An advantage in the present invention is to recognize that consumers typically have rectangular spaces in front of the fixture where it is desirable to cover the complete area, not just a fan shape near the sensor. With the adjustable motion sensor of the present invention, there is the ability to reduce the range in front of the motion sensor by aiming the movable sensor assembly downward. However, the range to the far left and right of the motion sensor are not grounded when the moveable sensor assembly is aimed downward and so the range on the sides of the sensor is not reduced as much as the range in the front of the sensor. The original rectangular shape can be retained by reducing sensor sensitivity when the sensor is aimed downward. In this case when the forward looking sensing beams are grounded, the sensitivity can be reduced to bring within the side to side coverage and retain the rectangular pattern. 
     The charts shown in  FIGS. 9-15  show different sensitivity levels at different sensor elevations and are provided as examples and not limitations of the sensitivity of the sensor assembly.  FIG. 9  shows an example of lens detection for people for maximum sensitivity, at maximum elevation.  FIG. 10  shows an example of lens detection for warmer objects for maximum sensitivity at maximum elevation. With warmer objects, the detection area in  FIG. 10  far exceeds the desired detection area indicated by the rectangle on the chart. 
     When the elevation of the sensor assembly is adjusted, the detection coverage area changes.  FIG. 11  shows an example of the lens detection for warmer objects for maximum sensitivity; for an elevation of approximately −3 degrees while  FIG. 12  shows the lens detection for people with maximum sensitivity at an elevation of approximately −3 degrees. While the detection pattern for people maintains the desired rectangular shape, the detection pattern for warmer objects shown in  FIG. 11  exceeds the desired range on the left and right sides. If it is desired to reduce the detection range on the left and right sides for warmer objects, reducing the sensitivity of the sensor assembly can also be used to change the sensor coverage area. Since the range of the forward looking sensing beams are limited by hitting the ground rather than sensitivity, the sensitivity can be reduced with little effect on the forward looking sensing beams while significantly reducing the range of the left and right sensing beams. 
       FIG. 13  shows an example of lens detection for warmer objects with a sensitivity of approximately 70% at an elevation of approximately −3 degrees. When compared to  FIG. 11 , it can be seen that the range of the left and right sensing beams is reduced with little effect on the forward sensing beams. Likewise,  FIG. 14  shows lens detection for people with a sensitivity of approximately 70% and an elevation of approximately −3 degrees. When sensitivity is further reduced to approximately 20%, the coverage area is further reduced as shown in  FIG. 15  when the corresponding elevation is approximately −10 degrees. 
     Those skilled in the art will understand that sensitivity and elevation can be set as precisely as desired, but their effects on range are quite variable. Passive IR motion sensors detect differences in temperature between the background and the object that is moving. This temperature differential and the speed of the object have dramatic effects on range. On a hot summer day when the air temperature is close to skin temperature, range can drop dramatically . . . over 90%. Similarly, if the object is moving very slowly or very fast, range is greatly reduced. Even if testing in a climate controlled environment, it would be difficult to make range measurements that were repeatable within 10%. The term “approximately” can be +/−10% of the amount referenced. Additionally, preferred amounts and ranges can include the amounts and ranges referenced without the prefix of being approximately. 
     While the invention has been described, disclosed, illustrated and shown in various terms of certain embodiments or modifications which it has presumed in practice, the scope of the invention is not intended to be, nor should it be deemed to be, limited thereby and such other modifications or embodiments as may be suggested by the teachings herein are particularly reserved especially as they fall within the breadth and scope of the claims here appended.