Abstract:
A highly efficient luminaire. The luminaire includes a light source that emits light. The emitted light is redirected by a light transformer having a curved circular reflective interior surface, the reflective interior surface reflecting the light in a predetermined pattern. A substantial amount of light being may be reflected close to an axis coincident with a radial line defining a radius of the circular reflective interior surface. Additionally, a substantial amount of light may be reflected in a pattern with low divergency or parallel with an axis of the light transformer. The light is transmitted to the exterior of the luminaire by an optical window.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of and claims priority to U.S. application Ser. No. 12/780,824 filed May 14, 2010 which is a continuation of U.S. application Ser. No. 11/930,423, filed Oct. 31, 2007, which is a continuation of U.S. application Ser. No. 10/277,230, filed Oct. 21, 2002, now U.S. Pat. No. 7,503,669, which is a continuation-in-part of U.S. application Ser. No. 09/566,521, filed May 8, 2000, now U.S. Pat. No. 6,543,911, and all of which are herein incorporated by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention is directed generally to lighting systems. More particularly, the present invention is directed to light transforming devices that provide a precisely determined light distribution pattern, such as those used for navigation, obstructions and other signal lights. 
     DESCRIPTION OF RELATED ART 
     Presently, lighting systems are used to mark obstructions and curves on roadways and paths on airport taxiways and runways. For example, airports incorporate a system of lighting to provide guidance to approaching and taxiing aircraft. Thousands of halogen lamps can be used in airports. Unfortunately, these lamps require excessive amounts of power. 
     In roadway lighting systems, lamps are placed around the obstructions and along roadway curves to signal the presence of the obstructions and curves to drivers. These lighting systems do not sufficiently redirect light in an optimal pattern for drivers. For example, the lamps do not provide adequate light to drivers located far away from the lamps. Accordingly, the lamps also do not compensate for an inverse square relationship of illuminance to distance as a driver approaches the lamp. In particular, the lamps do not adjust for the fact that a driver can see the lamp better when the driver is closer to the lamp. Additionally, most of such signal devices direct only a portion of light emitted by a light source in a useful pattern. Accordingly, they have low efficiency. Some in the prior art have sought to allow “hands-free” access to a user&#39;s voice mail messaging system. By way of example, without intending to limit the present invention, U.S. Pat. No. 6,868,142, issued on Mar. 15, 2005 to Gupta et al., discloses a voice-operated interface for communicating with a voice mail messaging system. A speech recognition unit is utilized to retrieve certain voice commands (e.g., “next”, “skip”, “repeat”) and then translate the commands into a proper tone sequence which is transmitted to the voice mail messaging system. The voice mail messaging system then retrieves and transmits the voice mail to the user. 
     SUMMARY OF THE INVENTION 
     The present invention provides a method and apparatus for a high efficiency redirected light emitted by a light source in a predetermined pattern by using an optical transformer with a precisely calculated reflective surface. In one embodiment, the present invention provides emitted light redirected by a light transformer having a curved circular reflective interior surface, the reflective interior surface reflecting the light in a predetermined pattern. For example, the reflective interior surface reflects the light with a substantial amount of light being reflected close to an axis coincident with a radial line defining a radius of the circular reflective interior surface. The light is transmitted to the exterior of the light transformer by an optical window. 
     In another embodiment, the present invention provides a light redirecting device for transmitting light with low divergence or substantially parallel with an axis of light direction. The device can include a first total internal reflection surface, a first member including a portion of the first total internal reflection surface, a first planar optical window located at an end of the first member, the first planar optical window being substantially perpendicular to the axis of light direction, and an aspheric lens adjacent to the first member. The device can further include a second total internal reflection surface symmetrical across the axis of light direction with the first total internal reflection surface, and a second member including a portion of the second total internal reflection surface, the second member symmetrical across the axis of light direction with the first member. The device can additionally include a second planar optical window located at an end of the second member, the second planar optical window being substantially perpendicular to the axis of light direction, the second planar optical window further being symmetrical across the axis of light direction with the first planar optical window. 
     In another embodiment, the present invention provides a light redirecting device that can include a first end that receives light from a light source, a second end that outputs the received light, the second end located on an opposite end of the device from the first end, a first member located on a third end of the light redirecting device the first member having an outer wall comprising a total internal reflection surface, a second member located on a fourth end of the light redirecting device, the fourth end located on an opposite end of the redirecting device from the third end, the second member having an outer wall comprising a total internal reflection surface, and an axis located between the third end and the fourth end, the axis being perpendicular to the first end. The first face and the second face can redirect the received light in a direction of the second end. 
     In another embodiment, the present invention provides a method for designing a reflective surface for a light transformer that can include the steps of receiving maximum and minimum output angles, receiving a location of a portion of the light transformer with respect to a light source that provides light, and iteratively, point-by-point, calculating an optical transformer reflective surface by providing for each increment of an input angle, an associated increment of the output angle which is consistent with predetermined output intensity distribution to reflect light provided by the light source according to the received maximum and minimum output angles based on the received location of a portion of the light transformer. 
     In another embodiment, the present invention provides an apparatus for transforming and emitting light that can include a light source that emits light, a light transformer having a curved circular reflective interior surface, the reflective interior surface reflecting the light emitted by the light source in a predetermined pattern with a substantial amount of light being reflected close to an axis coincident with a radial line defining a radius of the circular reflective interior surface and an optical window the transmits the light to the exterior of the light transformer. The reflective interior surface can reflect the light at an angle α to achieve an intensity proportional to 1/(tan 2α ). The reflective interior surface can further reflects light rays of the light at different angles to compensate for an inverse proportional relationship between perceived intensity and distance from a light source. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The preferred embodiments of the present invention will be described with reference to the following figures, wherein like numerals designate like elements, and wherein: 
         FIG. 1  is an exemplary perspective view of a light transformer according to one embodiment; 
         FIG. 2  is another exemplary perspective view of a light transformer according to one embodiment; 
         FIG. 3  is a cross-sectional diagram of a semi-flush omnidirectional luminaire according to another embodiment; 
         FIG. 4  is an exemplary perspective view of a light transformer according to another embodiment; 
         FIG. 5  is an exemplary top view of a lighting system for a light transformer according to another embodiment; 
         FIG. 6  is a cross-sectional diagram of a light transformer according to another embodiment; 
         FIG. 7  is another cross-sectional diagram of a light transformer according to another embodiment; 
         FIG. 8  is an exemplary block diagram of a light transformer design system; 
         FIG. 9  is an exemplary block diagram of a light transformer design module; 
         FIG. 10  is an exemplary illustration of an omnidirectional light transformer system; 
         FIGS. 11(   a )- 11 ( c ) are exemplary illustrations of inverse square law compensation using source luminous intensity; 
         FIG. 12  is an exemplary illustration of how a reflective surface is designed; 
         FIG. 13  is an illustration of an exemplary flowchart for the design of a light transformer; 
         FIGS. 14(   a )- 14 ( c ) are exemplary illustrations of a system that provides an omnidirectional light pattern in a horizontal plane with precision predetermined luminous intensity distribution in a vertical plane; 
         FIGS. 15(   a ) and  15 ( b ) are exemplary illustrations of a resulting envelope and a overlapping intensity distribution pattern of a lighting system; 
         FIG. 16  is an exemplary illustration of a vertical cross section of a toroidal precision optical transformer; and 
         FIG. 17  is an exemplary illustration of an optical transformer for an elevated omnidirectional light transformer. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  is an exemplary perspective view of an integrated omnidirectional light transformer  100  according to one embodiment. The integrated light transformer  100  can include an optical window  110  and a support  120 . The optical window  110  may comprise an omnidirectional window or it may comprise any other means for transmitting light, such as lenses, diffusers or open areas. In operation, when it is desirable to distribute light out of the light transformer  100  in a 360 degree pattern, the light transformer  100  can be circular as illustrated. Other shapes and various masks can be used to effectuate different light distribution patterns. For example, part of the optical window  110  may be masked in order to distribute light out of only a portion of the light transformer  100 . 
       FIG. 2  is another exemplary perspective view of the light transformer  100  according to one embodiment.  FIG. 2  illustrates that the light transformer  100  can further include an arbitrary aspherical reflective surface  130 . The reflective surface  130  may be a curved conical reflective interior surface. In operation, light can be projected from the bottom of the light transformer onto the reflective surface  130 . The reflective surface  130  can then reflect the light through the optical window  110  out of the light transformer  100 . 
       FIG. 3  is a cross-sectional diagram of a semi-flush omnidirectional luminaire semi-flush omnidirectional luminaire  300  according to another embodiment. The semi-flush omnidirectional luminaire  300  can include a light transformer  100 , a light source  310 , a shell  320 , a connector  330 , a printed circuit board (PCB)  340  and light rays  350 - 352 . The semi-flush omnidirectional luminaire  300  can also include a gasket plate  360 , a rib  370 , a seal  380  and a bond  390 . The light source  310  may be a light emitting diode or any other device that emits light. The connector  330  may provide an electrical connection to outside circuitry that provides power and control for the semi-flush omnidirectional luminaire  300 . The PCB  340  can provide electrical connection for the light source  310 , the connector  330  and useful circuitry for operating the semi-flush omnidirectional luminaire  300 . The PCB  340  can also provide control circuitry and a power source so that the semi-flush omnidirectional luminaire  300  can operate autonomously from outside circuitry and power. 
     In operation, the light source  310  emits light rays  350 - 352  towards the reflective surface  130 . The light rays  350 - 352  are reflected in accordance with the curvature of the reflective surface  130 . A ray with a minimal angle with respect to the vertical axis is reflected in a direction of the maximum elevation (ray  352 ), and a ray with a maximum angle is reflected in a direction of minimum elevation (ray  350 ). Therefore, the waist of the outgoing beam will be formed in order to minimize the vertical size of the transmissive wall. Preferably, a higher percentage of the light rays  350 - 352  are reflected along the path of ray  350 . 
     For example, 70% of the light emitted from the light source  310  can be reflected substantially along the path of light ray  350 , 10% substantially along the path of light ray  352  and the remaining 20% substantially between paths  350  and  352 . Therefore, the luminaire  300  will have a luminous intensity higher at lower angles, and about all light emitted by the light source will be directed in a predetermined pattern. In particular, the luminaire  300  can redirect the light so that illuminance at a long range distance (i.e. at the lower observation angles) will be equal to illuminance at a short range distance (i.e. at the higher observation angles). Therefore, as a driver in a car approaches the luminaire  300 , the driver can perceive light of equal intensity at long distances and at short distances from the luminaire  300 . 
       FIG. 4  is an exemplary perspective view of a luminaire  500  according to another embodiment. The luminaire  500  can include a light transformer  600  and a lighting system  800  comprising multiple light sources  700 . In operation, the light transformer  600  can be placed over the lighting system  800  to receive and distribute light from the light sources  700 . 
       FIG. 5  is an exemplary top view of a lighting system  800  for a light transformer according to another embodiment. The lighting system can include light sources  700 . The light sources  700  can be LEDs or any other device useful for emitting light. The light sources  700  may surround the lighting system  800  or the light sources may partially surround the lighting system  800  to only emit light out of part of the lighting system  800 . 
       FIG. 6  is an exemplary cross-sectional diagram of a light transformer  600  according to another embodiment. The light transformer  600  may include a window such as a window  610 , an aspherical lens  620 , total internal reflection surfaces (TIR)  630  and  635  and clear windows or optical windows  640  and  645 . The TIR surfaces  630  and  635  may be curved circular reflective interior surfaces or arbitrary aspherical reflective surfaces. 
       FIG. 7  is another exemplary cross-sectional diagram of a light transformer according to another embodiment.  FIG. 7  illustrates a light source  700  distributing light rays  710 - 750  to a portion of the light transformer  600 . The light source may be a LED or any other device useful for emitting light. In operation, the light source  700  radiates light rays  710 - 750  towards the light transformer  600 . The light rays  710 - 750  enter the light transformer  600  at the window  610 . As illustrated, light ray  730  propagates straight from the light source along an axis coincident with a radial line defining a radius of the circular reflective interior surface. Those light rays  720 ,  730  and  740  which travel directly to the surface  620  are refracted in a direction with low divergence or substantially parallel to light ray  730 . Those light rays  750  and  760  which travel to surfaces  630  and  635  are reflected through clear windows  640  and  645  in a direction with low divergence or substantially parallel to light ray  730 . 
       FIG. 8  is an exemplary block diagram of a light transformer design system  900 . The light transformer design system  900  can include a design processing unit  910 , an input device  920 , an output device  930  and a database  940 . The design processing unit  910  may be a processor, a personal computer, a mainframe computer, a palm computer or any other device useful for processing data. The input device  920  may be a keyboard, a voice recognition system, a modem, a scanner or any other device useful for inputting data. The output device  930  may be a video monitor, a printer, a modem or any other device useful for outputting data. The output device  930  may also be a machining system for manufacturing a light transformer. The database  940  may be located in memory on the design processing unit  910 , on a compact disk, on a floppy disk, on a hard drive or on any other device useful for storing data. 
     In operation, the input device  920  is used to input data to the design processing unit  910 . The data may be input by a user of the system  900 . The design processing unit  910  can process the data and store the data on the database  940 . The design processing unit  910  can also retrieve data from the database  940  for processing. The design processing unit  910  can further send data to the output device  930 . The output device  930  may print out or display the data to a user. The output device  930  may additionally machine a light transformer based on the data. 
       FIG. 9  is an exemplary block diagram of a light transformer design module  1000 . The light transformer design module  1000  may include a controller  1050 , a memory  1040 , an input/output (I/O) interface  1010 , a database interface  1020  and a bus  1030 . The controller  1050  controls the operation of the light transformer design system  900  and communicates with the input device  920  and the output device  930  through the network interface  1010  and the database  940  via the database interface  1020 . In operation, when a designer uses input device  920 , for example, the design processing unit  910  may be accessed and the communication signals may be routed by the controller  1050  to the design processing unit  910 . 
     In an exemplary embodiment, the controller  1050  operates in accordance with the invention by receiving maximum and minimum output angles and receiving a location of a portion of the light transformer with respect to a light source. The controller  1050  can iteratively calculate points on the light transformer to reflect light provided by the light source according to the received maximum and minimum output angles based on the received location of a portion of the light transformer. 
     The design module  1000  can be used to create an arbitrary aspherical reflective surface, for example, reflective surfaces  130 ,  630  or  635  that will provide equal omnidirectional patterns in a horizontal space with precisely predetermined luminous intensity distribution in the vertical plane utilizing a single light source or multiple light sources with given photometric characteristics. 
       FIG. 10  is an exemplary illustration of an omnidirectional light transformer system  1100 . The omnidirectional light transformer system  1100  can include an omnidirectional light transformer  1110  such as the light transformer  1100  that has an omnidirectional window  1120  and an aspherical reflective surface  1130 . The omnidirectional light transformer system  1100  can also include a light source  1140  such as an LED. 
     The aspherical reflective surface  1130  can be designed so that all light rays emitted from the light source  1140  are reflected through the omnidirectional window  1120  at an angular domain between α′ min  and α′ max . A ray with a minimal angle, with respect to the vertical axis (α′ min ) should be reflected in the direction of the maximum elevation (α′ max ) and a ray with a maximum angle (α′ max ) should be reflected in the direction of the minimum elevation (α′ min ). Therefore, the waist of the outgoing beam will be formed in order to minimize the vertical size of the omnidirectional window. 
       FIGS. 11(   a )- 11 ( c ) are exemplary illustrations of inverse square law compensation using source luminous intensity with angle distribution ƒ(α′)=1/tan 2  (α′).  FIGS. 11(   a )- 11 ( c ) illustrate an observer  1220  observing light emitted from a light transformer or light source  1210 . For analysis, let the spatial light distribution of the light source  1210  be described by some known function ƒ(α). Assume that the light transformer output luminous intensity distribution, in the vertical plane, is described by and arbitrary function ƒ(α′), that satisfies the predetermined custom requirements. For example, if the requirement calls for equal visibility from different distances (i.e., to compensate for the inverse square law), this function should be inverse to tan 2 (α′). The inverse square law results in 
             E   =       I   ⁡     (   α   )       ⁢       I   ⁡     (   α   )         D   2               
where E is illuminance, I is the source luminous intensity and D is the distance. Because,
 
               D   =         H     tan   ⁢           ⁢   α       ⁢           ⁢   and   ⁢           ⁢     I   ⁡     (   α   )         =         EH   2     ⁢     1       tan   2     ⁢   α       ⁢           ⁢   or   ⁢           ⁢       f   ′     ⁡     (     α   ′     )         =     c       tan   2     ⁢     α   ′               ,         
where c is constant.
 
     The design of the reflective surface  1130  is an iterative process.  FIG. 12  is an exemplary illustration of how a reflective surface  1320  is designed step-by-step for the number of emitted rays AB, AC, etc. with increment Δα.  FIG. 12  includes a light source  1310  and an output window  1330 . If the reflective surface  1320  has been designed from the apex point O to point B, the next following point C of the reflective surface  1320  can be found from:
 
 a ·ƒ(α)·Δα=ƒ′(α′)·Δα′  (1)
 
where a is the constant for the full cycle of the design. The condition in Equation (1) means that output energy in sector Δα′ is equal to emitted energy in the sector Δα with the factor a. Factor a is shown in Equation (2):
 
     
       
         
           
             
               
                 
                   
                     a 
                     · 
                     
                       
                         ∫ 
                         0 
                         
                           α 
                           max 
                         
                       
                       ⁢ 
                       
                         
                           f 
                           ⁡ 
                           
                             ( 
                             α 
                             ) 
                           
                         
                         · 
                         Δα 
                       
                     
                   
                   = 
                   
                     
                       ∫ 
                       
                         α 
                         min 
                       
                       
                         α 
                         max 
                       
                     
                     ⁢ 
                     
                       
                         
                           f 
                           ′ 
                         
                         ⁡ 
                         
                           ( 
                           
                             α 
                             ′ 
                           
                           ) 
                         
                       
                       · 
                       
                         Δα 
                         ′ 
                       
                     
                   
                 
               
               
                 
                   ( 
                   2 
                   ) 
                 
               
             
           
         
       
     
     With the output power function ƒ′(α′) the boundary conditions α min  and α max  will determine factor a unambiguously. So as illustrated in  FIG. 12 , where α′=α′ F  and
 
α′ F =α′ L +Δα′  (3)
 
is the local angle of the reflection cone, β can be found from the reflection&#39;s law as:
 
                   β   =       (       90   °     -     α   F   ′     +     a   L   ′       )     2             (   4   )               
The coordinate of point C, which is next to the known point B can be found as the point of intersection of ray AC with the local conical surface from the system of linear equations:
 
 Y−Y   B =tan β·( Z   C   −Z   B )
 
 Y=Z ·tan α  (5)
 
where the second equation is the equation of ray from point A with angle α with respect to the z-axis. So,
 
                     Z   C     =         Y   B     -     tan   ⁢           ⁢     β   ·     Z   B               tan   ⁢           ⁢   α     -     tan   ⁢           ⁢   β                 (   6   )               
and,
 
 Y   C   =Z   C ·tan α  (7)
 
This can be repeated from point C to the new point of the reflective surface  1320  until the outgoing angle α′ will not reach α′ max .
 
       FIG. 13  is an illustration of an exemplary flowchart for the design of a light transformer by the controller  1050 . In step  1405 , initial data is received by the controller  1050 . The initial data can include the minimum angle, the maximum angle, and the location or distance of an initial design point (AO) of the light transformer with respect to a light source. In step  1410 , the controller  1050  calculates an asymmetrical reflective surface constant based on the input minimum and maximum angles. In step  1415 , the controller  1050  sets the initial points and angles for the design process. In step  1420 , the controller  1050  calculates local angles of the reflective surface of the light transformer. In step  1425 , the controller  1050  calculates the coordinates of the next point along the reflective surface of the light transformer. In step  1430 , the controller  1050  calculates the difference in the reflective angle of the reflective surface of the light transformer. In step  1435 , the controller  1050  sets new points for the reflective surface of the light transformer. In step  1440 , the controller  1050  determines whether the resulting calculated reflective angle is greater than the received minimum angle. If the calculated reflective angle is not greater than the received minimum angle, the controller  1050  returns to step  1420 . If the calculated reflective angle is greater than the received minimum angle, the controller  1050  advances to step  1445 . In step  1445 , the controller  1050  outputs the final design of the reflective surface of the light transformer. In step  1450 , the flowchart ends. 
     This method illustrates how the controller  1050  can design a light transformer to have a predetermined light distribution pattern. Accordingly, the controller  1050  iteratively calculates points on a light transformer to reflect light provided by a light source according to received maximum and minimum output angles based on a received location of a portion of the light transformer. 
     In some cases, when a single-source luminous intensity distribution does not provide adequate illumination to match desired specifications, an alternative design with multiple light sources, such as depicted in  FIG. 5  above, can be implemented.  FIGS. 14(   a )- 14 ( c ) are exemplary illustrations of a system  1500  that provides an omnidirectional light pattern in a horizontal plane with a precisely predetermined luminous intensity distribution in the vertical plane. A number of identical light sources  1510  form a circular array in the horizontal plane (XOY) and are encircled by a toroidal precision optical transformer  1520 . This transformer  1520  is designed to provide minimal impact of intensity distribution in the horizontal plane and predetermined precise intensity distribution in the vertical plane. For example,  FIG. 14(   b ) illustrates a cross-sectional side view of how the transformer provides intensity distribution from angle .beta. of input light to angle β′ of output light where β/ 2  and β′/ 2  represent half of β and β′ respectively. 
       FIG. 14(   c ) illustrates how a horizontal pattern is created by way of overlapping individual outgoing patterns α′ 1 , α′ 2 , α′ 3 , etc. When given a desired angular intensity distribution for a particular light source  1510 , it is possible to choose the number of light sources  1510  and their relative location to provide a horizontal envelope with predetermined non-uniformity.  FIGS. 15(   a ) and  15 ( b ) are exemplary illustrations of the resulting envelope and the overlapping intensity distribution pattern, respectively, of the system  1500 .  FIGS. 15(   a ) and  15 ( b ) illustrate an example using 10 LEDs located with equal angular separation of 36° that provide an envelope with non-uniformity of .+−0.5%. 
       FIG. 16  is an exemplary illustration of a vertical cross section of a toroidal precision optical transformer  1700 . A vertical pattern is created by a combination of an aspheric lens  1710  which is the central part of the optical transformer (AOB) and members  1720  and  1730 . For example, member  1730  includes the transformer periphery (CDE). The members  1720  and  1730  can include planar optical windows  1740  and  1750  and total internal reflection surfaces  1760  and  1770 . The aspheric lens  1710  transforms all rays emitted in angle β 1 /2 into the pattern limited by the outgoing ray with angle β′ max  (ray  1 ′, for example). The periphery performance is based on total internal reflection and, as a result, all rays emitted between angles and β 1 /2 and β 2 /2 will be reflected from the total internal reflection surface  1770  and through the planar optical window  1750 , directed in the domain between angles β″ min  and β″ max  (for example, ray  2 ′). Both aspherical lens profile and total internal reflection surface shapes may be calculated as functions of predetermined intensity distribution in the vertical plane using methodology and procedures described with respect to  FIGS. 9-14 . This concept and design provides light transformation with a very high ratio (β/β 1  up to 50) which is not practical with conventional aspheric optics because of unreasonable dimensions. 
       FIG. 17  is an exemplary illustration of an optical transformer for an elevated omnidirectional luminaire. The luminaire can include a light source  1810 , an input surface  1820 , a reflective surface  1830  and alight channel  1840 . The light source  1810  can be located a distance d from the input surface  1820 . Additionally, the input surface can be semispherical about a radius R. Furthermore, the reflective surface  1830  can be designed according to the method disclosed with reference to  FIGS. 9-14 . 
     In operation, the light source  1810  can transmit light through the input surface  1820 . The input surface  1820  can direct the light through the light channel  1840  by way of total internal reflection to the reflective surface  1830 . The reflective surface  1830  can reflect the light according to a specified distribution pattern. For example, the reflective surface  1830  can reflect the light at an angle α′ where α′ falls between α′ min  and α′ max . Additionally, the reflective surface can reflect the light in a manner similar to the semi-flush omnidirectional luminaire  300  of  FIG. 3 . 
     The method of this invention is preferably implemented on a programmed processor. However, the method may also be implemented on a general purpose or special purpose computer, a programmed microprocessor or microcontroller and peripheral integrated circuit elements, an ASIC or other integrated circuit, a hardware electronic or logic circuit such as a discrete element circuit, a programmable logic device such as a PLD, PLA, FPGA or PAL, or the like. In general, any device on which resides a finite state machine capable of implementing the flowcharts shown in the Figures may be used to implement the processor functions of this invention. 
     While this invention has been described with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, the preferred embodiments of the invention as set forth herein are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the invention.