Abstract:
Curing lights can be constructed using more than one LED, where at least 2 of the LEDs have different spectral profiles in order to have the capability to activate initiators sensitive to light of different wavelengths. A heat sink handle may be used to heat management.

Description:
PRIORITY  
       [0001]     This patent application claims benefit of and priority to U.S. Provisional Patent Application Ser. No. 60/686,281 filed on Jun. 1, 2005, which is hereby incorporated by reference. 
     
    
     BACKGROUND  
       [0002]     In the field of dentistry, and in other fields where monomers are polymerized using a light-sensitive initiator (i.e., cured), there is a need for a curing light that produces light across a wide spectrum of light wavelengths in order to cure various materials which use initiators sensitive to different light wavelengths.  
       SUMMARY  
       [0003]     Curing lights can be constructed using more than one LED, where at least 2 of the LEDs have different spectral profiles in order to have the capability to activate initiators sensitive to light of different wavelengths.  
     
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0004]      FIG. 1  depicts a cordless LED curing light and a charging unit.  
         [0005]      FIG. 2   a  depicts a cross sectional view of the curing light.  
         [0006]      FIG. 2   b  depicts another cross sectional view of the curing light.  
         [0007]      FIG. 3   a  depicts a distal view of the light source.  
         [0008]      FIG. 3   b  depicts a side view of the light source.  
         [0009]      FIG. 4  depicts a light module for the curing light.  
         [0010]      FIG. 5  depicts a control panel for the curing light. 
     
    
     DETAILED DESCRIPTION  
       [0011]     Devices disclosed include corded or cordless curing lights for curing light-curable composites and adhesives. A curing light can use two LEDs as light sources to provide e a wide output spectra to cure many different composites with different initiators. As an example, a first LED may output light at about 400 nm, while a second LED outputs light at about 470 nm. This provides a broader spectral output than using two LEDs of the same wavelength. The housing of the curing light can be used as a heat sink to managing the heat generated by the LEDs. The light has a unique display on the handle to communicate information to a user.  
         [0012]      FIG. 1  depicts curing light and its charger. A handle  101  is provided on which a display  102  is mounted for communicating information to a user.  
         [0013]     Control pad  103  permits a user to control operation of the curing light. Control pad  103  can be used to control things such as power level, mode of operation (pulsed, continuous wave, etc.) and timer. A detachable wand  104  may be provided. If desired, the wand  104  can be detachable from the handle  101 . The wand  104  includes a light module  105  from which light exits the curing light. A charger or charging base  106  is provided with a receptacle  107  for accepting the handle  101  therein. The handle  101  has one or more batteries within it which are charged by the charging base. A light meter  108  can be provided on the base for measuring light intensity output from the curing light. A display  109  indicating light intensity or charging status can be included. A cord  110  and power supply  111  operate with an AC outlet to charge the light.  
         [0014]      FIG. 2   a  depicts a cross-sectional view of the curing light of  FIG. 1  with the wand or light source detached from the body or handle. The curing light has two main parts, wand  201 , and main body or handle  202 . The wand is attached to the body through a matched quick connector  203  in wand side and  204  in body side. The wand  201  is held in the body by friction fit through a spring mechanism  205  and  206  on wand and body sides respectively. Heat can be transferred through the quick coupler from the wand to the handle of the curing light in order to move heat away from the LEDs and to avoid heat buildup which shortens the life of LEDs and which can be dangerous to a patient in a dental application.  
         [0015]      FIG. 2   b  depicts another cross-sectional view of the curing light. In the body  202 , there is a housing  207  which is being made of metal materials. The interior  207  of the body includes a control circuit  208  which controls the electrical and optical properties of the curing light. A rechargeable battery  209  is included. Control pad  210  and display screen  211  are also provided. An input  212  for charging the battery is located at the end of main body  202 . A quick connect  204  is embedded in the main body  202 . A metal ring  213  is attached to metal housing  207 . A matching metal ring  214  is on the wand side  201  for friction fit between the wand and handle. The ring  214  can be a separate part or integral with the heatsink  215  which is inside housing  216 . There is an insulation layer  217  between wand housing  216  and heatsink  215 . On the heatsink  215 , there are two mounting platforms  218  and  219  for LED mounting. Two LEDs  220  and  221  are placed on top of the two mounting platforms with heat conductive paste  222  between LEDs and the heatsink to facilitate heat transfer. LEDs  220  and  221  are attached to the heatsink through a reflector  223  and screws  224  and  225 .  
         [0016]      FIG. 3   a  depicts a top view of a light exit on the wand. A reflector  301  with a reflection cone  302  are used to gather and reflect light from two LEDs  303  and  304  which are inside the reflection cone  302 . Two screws  305  and  306  are used to attache reflector and LEDs to the heatsink.  
         [0017]      FIG. 3   b  depicts a cross-sectional view of the light exit section of the curing light. The heat sink  207  has two mounting platforms or facets  308  and  309 . The two facets  308  and  309  are arranged at an angel  310  to position the two LEDs  303  and  304  such a way to stratify the light beam requirement. The LEDs are attached to heatsink using reflector  301  and screws  305  and  306 . Heat conduction paste between the LEDs and the heat sink facet. In this construct, if the LEDs are not working for any reason, they can be changed by removing screws from the heat sink. The light beam  313  exits to create a footprint  314 . The shape of the footprint  314  can be oval, circular or any shape desired. The combination of LED emitting pattern, arrangement angle of metal facets and the shape of the light reflector cone determines the shape and profile of the light beam. The wavelength of each LED can range from 280 to 5000 nm or otherwise.  
         [0018]      FIG. 4  depicts a side view of an LED module. Generally there is a heat sink  401  with a reflective wall of a well  402 . Sometimes, there is no need for reflector  402 . A chip carrier  403  with a chip  404  placed on top is attached to heatsink  401 . Sometimes, the chip can be directly attached to heatsink  401  without carrier  403 . The chip electrodes are connected through wire  405   a  and  406   b  to electrodes  406   a  and  406   b  in the housing. A optical lens or other optical means  407  is placed on top of heatsink  401  to get a desired optical beam from the chip. There is a housing  208  outside of the heat sink for protection purposes. Sometimes, the housing may not be needed when different heatsink materials is used.  
         [0019]      FIG. 5  depicts an example display for the curing light. The display can be made of LEDs, LCD and other means. On the display, there is a timer indicator  501  to illustrate the time setting. There are 4 indicators for curing mode. An indicator  502  indicates constant output power curing mode. Another indicator  503  indicates ramping output power curing mode. Another indicator  504  indicates pulse curing mode. Indicator  505  indicates boost power curing mode. There is a battery status indicator  506  which informs the user of the status of the curing light battery. There are three status indicators for the battery. Indicator  507  indicates the battery is full. Indicator  508  indicates the battery is being charged. Indicator  509  indicates that the battery is low and needs to be charged.  
         [0020]      FIG. 6  depicts an example the light spectrum output profile when the curing light uses 2 LEDs of different peak wavelengths in order to provide a broad spectrum curing light. As shown, there are two peaks in the light profile. A first peak  601  is located between 350 and 430 nm. A second peak  602  is located in the 440 to 490 nm range. There is a valley between two peaks. Depending on the combination of LEDs, the output spectra can have one peak located between 350 and 430 nm and another between 430 and 490 nm. A two peak profile is useful in curing a variety of composites with different initiators.  
         [0021]     While the present invention has been described and illustrated in conjunction with a number of specific embodiments, those skilled in the art will appreciate that variations and modifications may be made without departing from the principles of the invention as herein illustrated, described, and claimed. The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects as only illustrative, and not restrictive. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.