Abstract:
An application for a light source for killing blood pathogens. The light source includes multiple ultraviolet light emitting diodes and a visible-spectrum light emitting diode. A light mixer combines light from the ultraviolet light emitting diodes and the visible-spectrum light emitting diode and focuses a mixed light into a fiber optic for delivery to an intravenous needle. A controller adjusts an amount of current delivered to the ultraviolet light emitting diodes and visible-spectrum light emitting diode. A touch screen is interfaced to the controller for inputting commands and a display is interfaced to the controller for outputting information.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. Pat. App. Ser. No. 11/686,767 (filed Mar. 15, 2007) and said document is hereby incorporated by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to the field of using light rays to kill pathogenic organisms and more particularly to a system and apparatus for emitting ultraviolet and visible light at controlled intensities. 
       BACKGROUND OF THE INVENTION 
       [0003]    It is well known to use ultraviolet light (UV) to kill pathogens in a liquid such as water. Many systems exist to expose liquids to ultraviolet light with the object of destroying pathogens. Additionally, it is well know to guide fiber optic instruments into arterial blood vessels. U.S. Pat. No. 4,830,460 to Goldenberg describes using ultraviolet light laser energy to ablate atherosclerotic plaque. U.S. Pat. No. 5,053,033 to Clarke describes an optical fiber for delivering ultraviolet light radiation to a blood vessel site following angioplasty to kill aortic muscle cells at the sight. U.S. Pat. No. 6,117,128 to Gregory describes a source of laser energy coupled to an optical fiber that is transported by a catheter to treat vascular thrombosis disorders in the brain. U.S. Pat. No. 6,187,030 to Gart describes a flexible fiber optic bundle connected to a light source for the treatment of internal and external diseases. 
         [0004]    U.S. Pat. No. 6,908,460 to DiStefano describes an apparatus for conveying light through an intravenous needle to kill blood pathogens and is hereby incorporated by reference. This patent describes using a combination of ultraviolet light and visible light (e.g., white light) alternately though an optical fiber and into a patient&#39;s venous system to kill pathogens in the venous system. The ultraviolet light kills pathogens such as bacteria, virus, fungi, molds and other unclassified pathogens. This patent describes a treatment of exposure to ultraviolet light of 200 to 450 nanometers in wavelength for around 30 minutes and exposure to visible light of 450 to 1100 nanometers in wavelength for another 30 minutes. This patent does not describe a method or apparatus for generating the desired wavelengths of light, nor for controlling the energy levels and duration of the light. 
         [0005]    What is needed is an apparatus that will generate a selected wavelength of light at a selected power level for a specified duration of time. 
       SUMMARY OF THE INVENTION 
       [0006]    In one embodiment, a light source for killing blood pathogens is disclosed including at least two light emitting diodes and a device for combining light from the light emitting diodes into a mixed light and focusing the mixed light into a fiber optic for delivery to an intravenous needle. A controller is provided for programmatically controlling the light emitting diodes and has an input device for inputting commands and an output device for displaying information. 
         [0007]    In another embodiment, a light source for killing blood pathogens is disclosed including ultraviolet light emitting diodes and a visible-spectrum light emitting diode. A light mixer combines light from the ultraviolet light emitting diodes and the visible-spectrum light emitting diode and focuses a mixed light into a fiber optic for delivery to an intravenous needle. A controller adjusts an amount of current delivered to the ultraviolet light emitting diodes and visible-spectrum light emitting diode. A touch screen is interfaced to the controller for inputting commands and a display is interfaced to the controller for outputting information. 
         [0008]    In another embodiment, a light source for killing blood pathogens is disclosed including ultraviolet light emitting diodes, each emitting light at a different wavelength and a visible-spectrum light emitting diode. A light mixer combines light from the ultraviolet light emitting diodes and the visible-spectrum light emitting diode and focuses the light into a fiber optic for delivery to an intravenous needle. A controller adjusts the amount of current delivered to the ultraviolet light emitting diodes and to the visible-spectrum light emitting diode. A minority of the light is reflected onto a photodiode which is coupled to the controller. A touch screen is provided for inputting commands and a display for outputting information. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    The invention can be best understood by those having ordinary skill in the art by reference to the following detailed description when considered in conjunction with the accompanying drawings in which: 
           [0010]      FIG. 1  illustrates a block diagram of a controller of the present invention. 
           [0011]      FIG. 2  illustrates a schematic view of the light sources of the present invention. 
           [0012]      FIG. 3  illustrates an isometric view of a typical enclosure for the present invention. 
           [0013]      FIG. 4  illustrates an isometric view of the interrelationship between the light sources, photo detector and fiber optics of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0014]    Reference will now be made in detail to the presently preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Throughout the following detailed description, the same reference numerals refer to the same elements in all figures. 
         [0015]    Referring to  FIG. 1 , a block diagram of a controller of the present invention is shown. This system is designed to deliver user selectable optical power at user selectable wavelengths delivered to the patient via, for example, a high performance UV transmitting fiber optic cable, preferably a silica fiber optic cable. The system is configured to provide a single or multiple concurrent treatments. The sources of light are preferably solid state LEDs (Light Emitting Diodes) emitting light at their fundamental wavelengths. In the preferred embodiment, there are four ultraviolet LEDs delivering light power in the high-UVB and UVA portion of the spectrum, (290 nm-365 nm). Also in the preferred embodiment, visible energy is emitted by a separate LED which delivers light with wavelengths of from 450 nm to 750 nm. 
         [0016]    The controller  100  has a processor  110  which can be any microprocessor or controller such as an Intel 80C51 or the like. In some embodiments, the processor uses external memory  112  to store data and instructions while in other embodiments, the processor has imbedded memory while in still other embodiments, both external memory  112  and internal memory are used. In the preferred embodiment, programs (firmware) are stored in persistent memory  114  until they are executed after loading them in memory  112 . There are many forms of persistent memory  114  that are possible including, but not limited to, flash, ROM, EPROM, EEPROM, magnetic storage, etc. The processor communicates with input/output devices through a bus  116 . 
         [0017]    A set of output bits coupled to the bus  116  are used to control various lamps  116  and other indicia. For example, indicator LEDs or lamps on the front panel indicate power on (e.g., green), ultraviolet treatment active (e.g., Blue) and visible light treatment (e.g., white led). In the preferred embodiment, operator input is accepted from a touch screen  128  and operator display communications are presented on a display  126 , preferably a graphics display such as a liquid crystal display (LCD). To communicate with the outside world, an interface, such as a universal serial bus (USB) interface  124 , is provided. This USB interface  124  is used, for example, to load/reload/update firmware and to transfer patient treatment data. 
         [0018]    Being that the light output from the present invention is injected into a living creature, it is important that the wavelength, optical power output and duration be tightly controlled. The wavelength is controlled by selecting one or more ultraviolet and visible light emitting diodes  141 / 143 / 145 / 147  (see  FIG. 2 ), each having a light output at a fundamental wavelength. In one embodiment, each LED  141 / 143 / 145 / 147  is encapsulated in a separate package. In other embodiments, some of the LEDs  141 / 143 / 145 / 147  are encapsulated in a common package while other LEDs  141 / 143 / 145 / 147  are encapsulated in different packages. In other embodiments, all of the LEDs  141 / 143 / 145 / 147  are encapsulated in one common package. 
         [0019]    The controller  100 , under program control, adjusts the optical power output of each light emitting diode through a set of LED control output ports  120  that are coupled to one or more digital to analog converters (DACs)  121 . The outputs of the DACs  121  drive the light emitting diodes  141 / 143 / 145 / 147  though current or voltage drivers  140 / 142 / 144 / 146  (see  FIG. 2 ). The duration is controlled by timers  113  internal to the processor  110  of the controller. 
         [0020]    Because of manufacturing variance and temperature-related variances, the optical power output is not deterministic based upon the current delivered to the LED(s)  141 / 143 / 145 / 147 . To better control the optical power output, the light output of the LED(s) is monitored with an optical sensor  160  (see  FIG. 2 ) such as a photodiode or the like. The signal from the optical sensor is converted to digital by an analog to digital (ADC) converter  123  and inputted to the processor  110  through an input port  122 . In this way, the processor  110  monitors the optical power output and adjusts the output values delivered to the LED control  120  when the optical power exceeds or under runs the desired optical power output level. 
         [0021]    Referring now to  FIG. 2 , a schematic view of the light sources and current drivers of the present invention will be described. Each LED  141 / 143 / 145 / 147  is driven by a LED driver  140 / 142 / 144 / 146 . LED drivers are well known in the industry, some of which are current source drivers. Each of the LED drivers  140 / 142 / 144 / 146  has as an input an analog LED drive signal from the controller DAC  121  ( FIG. 1 ). Each LED driver  140 / 142 / 144 / 146  provides a current (voltage) proportional to the analog LED drive signal that is connected to its corresponding LED  141 / 143 / 145 / 147 . The LED  141 / 143 / 145 / 147  will output light at an intensity proportional to this current (voltage). In this embodiment, the light output of each LED is directed toward a filter  150 / 152 / 154 / 156 . The LEDs are arranged in order of light output wavelength and, in this example, the filters  150 / 152 / 154 / 156  allow the light from the previous LED to pass through while reflecting light at the wavelength of the filter&#39;s  150 / 152 / 154 / 156  corresponding LED. For example, LED 1   141  is the highest wavelength and LED 4   147  is the lowest wavelength. In other embodiments, LED 1   141  is the lowest wavelength and LED 4   147  is the highest wavelength. The first filter  150  reflects the light output of LED 1   141 . The second filter  152  allows light of higher wavelengths than LED  2   143  to pass through it while reflecting wavelength less than or equal to LED  2   143 . Therefore, the light from LED 1   141 , reflected off the first filter  150  passes through the second filter  152  while the light from LED 2   143  reflects off of the second filter  152 . Each subsequent stage functions similarly. Each filter is angled at approximately 45 degrees from the path of light from the LEDs  141 / 143 / 145 / 147  and aligned to direct the light output from all LEDs into the fiber optic lens  162  and subsequently through the fiber optic cable  164  to the tip of the needle in the patient&#39;s venous system (not shown). Before the light output reaches the fiber optic lens  162 , a substantially transparent filter  158  directs a very small percentage of the light to the detector  160 . The detector  160  is any photo detector capable of measuring light intensity at the wavelengths used the system and outputting an analog signal (voltage, current or impedance) representative of the light power output. The output light power level signal is connected to the input of the ADC  123  of the controller  100 . The firmware of the present system periodically samples the output power level from the ADC  123  and adjusts the output levels of the DACs  121  to compensate for any over or under power levels with respect to the user&#39;s settings. 
         [0022]    Referring now to  FIG. 3 , an isometric view of a typical enclosure for the present invention will be described. In this embodiment, an enclosure  170  contains the internal circuitry of the light source of the present invention including the controller  100  and associated input/output subsystems, the LEDs and drivers  141 / 143 / 145 / 147 , optics  150 / 152 / 154 / 156 / 158 / 162 , and detector  160  (all not visible in  FIG. 3 ). Additionally, indicator lamps indicate power on  172  (e.g., green), ultraviolet treatment active  174  (e.g., Blue) and visible light treatment active  176  (e.g., white led). The LCD display and touch screen  182  is preferably located on an upper surface of the enclosure  170 . A power switch  178  is provided to turn the system on and off. A fiber optic connector  180  is provided to connect to the fiber optic cable (not shown) that transmits light from the light source of the present invention to the tip of a needle (not shown) that is inserted into the patient&#39;s venous system. 
         [0023]    Referring now to  FIG. 4 , an isometric view of the interrelationship between the light sources, photo detector and fiber optics of the present invention will be described. In this embodiment, multiple ultra violet LEDs are encapsulated into a single package  200  and the ultraviolet light  230  is aimed at a filter  202 . The filter  202  passes most of (a majority) the ultraviolet light  230  while reflecting a minimal amount or minority of light  232 . The minority of ultraviolet light  230  that does not pass through the filter  202  is reflected  232  onto a photo detector&#39;s  214  lens  215 . In this way, the photo detector  214  monitors the power output of the ultraviolet light source  200 . The majority of the ultraviolet light  230  from the ultraviolet light source  200  mixes with visible light  234  that is emitted from, for example, a white LED  204 , focused with a lens  206 . The combined ultraviolet and visible light  236  is focused by a lens  208  onto the optics  212  of a fiber optic lens  210  and passed out of the system on a fiber optic cable (not shown). The system of  FIG. 4  is one example of how the ultraviolet light and visible light are combined and delivered to the fiber optic. There are many ways known to mix light from different sources and focus the light including lenses, mirrors, filters, prisms and the like and the present invention is not limited to the exemplary embodiment. Furthermore, the system of the present invention is intended to emit any single or combined wavelength of light from one or several of the ultraviolet and visible LEDs. 
         [0024]    Equivalent elements can be substituted for the ones set forth above such that they perform in substantially the same manner in substantially the same way for achieving substantially the same result. 
         [0025]    It is believed that the system and method of the present invention and many of its attendant advantages will be understood by the foregoing description. It is also believed that it will be apparent that various changes may be made in the form, construction and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely exemplary and explanatory embodiment thereof. It is the intention of the following claims to encompass and include such changes.