Abstract:
The present invention discloses a unique and novel combination light source and active light filtering system for microscopes that eliminates the need for individual color filters, fluorescence filters, and many other filter types. The present invention provides variable light wavelength generating capabilities, and all of the benefits of most commercially available light sources in a compact package that can be mounted on a microscope or used at a distance from a microscope, but be coupled to it through a fiber optic cable or other light transmission means. Additionally, the present invention eliminates the need for a filter wheel turret in a microscope&#39;s optical path, as well as eliminates the need for multiple fluorescent filter blocks in a fluorescent microscope optical path. The present invention can improve microscope filter systems to enable effective imaging of live cells without staining.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to filters used to modify the wavelengths of light applied to specimens on microscopes. 
       BRIEF DESCRIPTION OF PRIOR ART 
       [0002]    Most high quality research grade microscopes use one or more separate filters to modify the light emitted from a light source directed at a specimen placed in the optical path of said microscope. These filters may be phase contrast, fluorescent, prism, band pass, dichroic, or simple colored gels used to block or allow the transmission of certain wavelengths of light. In all cases of prior art, the filters are passive devices. Further, said light sources aimed at said filters may be mercury vapor, halogen, LED, laser, or any other type of visible and invisible light sources. 
         [0003]    Prior art discloses myriad types and styles of the aforementioned filters and light sources. However, in all cases of prior art, each filter is manufactured as a separate component intended to be inserted in a carrier in a microscope system and is designed to effect only one very specific wavelength—or a very narrow area of specific wavelengths—of light. Because of this limitation, a microscope can typically hold just a few filters in its optical path system. Often, these filters are provided in a rotating turret configuration. Also, each light source type has very specific and limited wavelength characteristics. 
         [0004]    There is extensive prior art disclosing video projectors that use various types of translucent display panels driven by video generator hardware, a light source, and a lens to provide enlarged video images. 
         [0005]    For many years, in DLP, LCD, or LCOS video projectors, colors were produced either with multiple DLP, LCD, or LCOS panels, or in a single DLP panel system, by placing a color wheel between a white lamp and the DLP chip. In state of the art video projectors, multi-color (RGB) LED and laser illuminated single-chip projectors are able to eliminate the spinning wheel and provide a wide array of colors needed. 
         [0006]    No video projection system was ever intended to be interfaced to microscopes. However, the present invention takes advantage of the current state of the art in RGB and RGBW LED, RGB laser technology, and other emerging multi-color light source systems in a unique and novel system design to provide variable intensity, variable wavelength light source and active light filtering functions for microscopes. 
       BRIEF SUMMARY OF THE INVENTION 
       [0007]    The present invention discloses a unique and novel combination light source and light filtering system for microscopes that provides an active filter set of almost unlimited light wavelength generation and modification capabilities, as well as providing all of the benefits of most commercially available microscope light sources in a compact package that can be mounted on a microscope or used at a distance from a microscope yet be coupled to it through a fiber optic cable or other light transmission means. Additionally, the present invention can eliminate the need for a filter wheel turret in a microscope&#39;s optical path, as well as eliminate the need for multiple fluorescent filter blocks in a fluorescent microscope system. 
         [0008]    In the preferred embodiment of the present invention components are combined from several unrelated industries to improve the state of the art in microscopic specimen analysis. In the preferred embodiment, a single RGB (red, green, blue) or RGBW (red, green, blue, and white) LED (light emitting diode) panel, a multi-color laser panel, or an equivalent variable color, variable wavelength light emitting panel, is driven by a microprocessor based controller. The microprocessor incorporates a software component coded to output all wavelengths of light available within the limits of said microprocessor and the display capabilities of said panel. A user interface and video display is provided to scroll through any or all of said available colors, shapes, or shades and “lock in” the color of choice—thereby creating a customized combined light source and filter. A color mixing, light collimating, or light condensing lens may also be used to modify the light output from said panel in the optical path of a microscope. 
         [0009]    Another embodiment of the present invention, specifically intended for use in fluorescence microscopy, combines two of the aforementioned panel/lens/microprocessor units, but configured in a typical fluorescent filter block with a dichroic mirror, wherein one panel set acts as the excitation filter which passes only the wavelength of light necessary for excitation of a fluorophore. The dichroic mirror is the optical element that separates the excitation light from the fluorophore fluorescence. The second panel set acts as the barrier filter to separate fluorescence emanating from the fluorophore from other background light. 
         [0010]    The foregoing embodiments, as well as other advantageous features of the embodiments, are explained in more detail with reference to drawings. Therefore, the same or similar reference numbers and components are used, as far as possible, to refer to the same or similar elements in all drawing figures. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a system flow chart of the present invention using one active panel. 
           [0012]      FIG. 2  is a system flow chart of the present invention as a fluorescent filter block. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0013]    The preferred embodiment of the present invention as displayed in the system design flow chart in  FIG. 1  incorporates an RGB (red, green, blue) or RGBW (red, green, blue, and white) LED (light emitting diode) light source, a multi-color laser light source, or a substantially functionally equivalent variable color, variable wavelength light emitting light source panel  20 . For example, said panel  20  may be a Luminus Devices SBT or PT series product, a Sony RGB Projection Laser system, a Laser Light Engines product, or a similar device using light producing elements capable of being controlled to output a wide range of colors or wavelengths of light. Said panel  20  is electrically interfaced to a microprocessor module  24 . 
         [0014]    Software program  26  is incorporated into module  24 , either as firmware, or as updateable software code through a USB or equivalent buss  28 . Program  26  is configured to enable said module  24  to control said panel  20  to provide visible or invisible colors, or any wavelengths of light which said panel  20  is capable of producing. 
         [0015]    A video monitor  30 , which may be a typical compact LCD or equivalent, black and white or color display of the type commonly used in computer monitors, laptop computers, or cellular phones, is electrically interfaced to a video driver circuit  19 , which is in turn electrically interfaced to, and controlled by module  24 . User interface  34  can be a mouse, joystick, or any other device which is interfaced to module  24  through buss  28  to enable selection of a wavelength of light or color in module  24 , the code for which is integrated into program  26 , and said wavelength of light or color being presented to a user on said display  30 . 
         [0016]    User interface  34  incorporates at least one simple switch or button  36  to “lock in” said wavelength of light or color selection in said program  26  for purposes of output by said panel  20  and display on said monitor  30 . Module  24  may provide video signals to circuit  19  so that the image and colors shown to a user are either different, or substantially identical on display  30  and panel  20 . 
         [0017]    Light path guide  38  can be an air space, mirrors, a simple hollow coupler, a fiber optic cable, or any other means capable of conducting the light output of panel  20  toward an objective lens  64  in a viewing device  40 . Light guide  38  may or may not incorporate a color mixing lens  32 , or a condensing or collimating lens  39 . Device  40  in most cases will be a microscope, but can also be any other device which can benefit from the use of filtered light. 
         [0018]    In the preferred embodiment of the present invention as displayed in  FIG. 2 , panel  20  is mounted to a panel carrier  58 . A color mixing lens  32  may be mounted between panel  20  and said carrier  58 . In certain cases, for a certain panel  20 , lens  32  may not be necessary. Another panel  21 , substantially equivalent in function to panel  20 , is also mechanically coupled to carrier  58  such that its light output is applied at an angle to said panel  20 . In order to provide this function, panel  21  may first need to be coupled to a translucent light guide  23  to allow said light output placement in the correct angle and location on said carrier  58 . 
         [0019]    A color mixing lens  34  may be mounted in between said panel  21  and light guide  23 , or in between said light guide  23  and carrier  58 . Lens  34  is shown in solid and dotted lines in  FIG. 2  to indicate the two possible locations. In certain cases, with certain types of panels  21 , said color mixing lens  34  may not be necessary. Said guide  23  may be a fiber optic or other light transmitting translucent panel capable of being side lighted or otherwise illuminated by panel  21  to allow the light that is output from said panel  20  to also pass through said guide  23 . In certain cases, with certain types of panels  21 , guide  23  may not be necessary, and panel  21  may be mounted directly to said carrier  58 . A dotted arc line with arrowheads indicates a variation of panel  21  mounting. 
         [0020]    Dichroic mirror  60  is also mounted to carrier  58  at an angle such that light emitted by panel  20  can pass through dichroic mirror  60  and panel  21 , or guide  23 , to exit carrier  58  toward light guide  38 , which can be a simple hollow coupler, mirrors, a fiber optic cable, a color mixing lens, or any other means to direct the light output of panels  20  and  21  toward a viewing device  40 —which may be any kind of microscope or other device which can benefit from the present invention. 
         [0021]    For ease of understanding and illustration, schematic microscopes are used in  FIGS. 1 and 2  provided herein where a viewing device  40  is designated by number. 
         [0022]    In this  FIG. 2  embodiment, an intended primary usage is in fluorescence microscopy, wherein excitation light signal  67  passing through carrier  58  may be directed by dichroic mirror  60  to pass through an objective lens  64  and strike a fluorophore  65  in a specimen  66 , causing said fluorophore  65  to fluoresce and provide a return light signal  68  that travels back through objective lens  64  and on through light path guide  38  to be viewed by a user. 
         [0023]    In this  FIG. 2  embodiment, panel  20 , controlled by module  24 , acts as an excitation filter which passes only the wavelength of light necessary for excitation light signal  67  to a specific fluorophore  65 . The dichroic mirror  60  is the optical element that separates the excitation light from the fluorescence return light signal  68 . Panel  21  is electrically interfaced to, and also controlled by module  24 . Panel  21 , or panel  21  in conjunction with guide  23 , acts as the barrier filter to separate fluorescence emanating from the fluorophore  65  from other background light. 
         [0024]    In this  FIG. 2  embodiment, software program  27  incorporates all the capabilities of software program  26 , but with the added functionality of using fluorescence filter lookup table  70  to automatically choose the wavelength of light or color displayed on said panel  21  in response to a user selection of the wavelength of light or color applied to, and displayed by, said panel  20 . Excitation and barrier filter combination lookup table  70  will incorporate substantially all known existing art data regarding excitation and barrier filter combinations so as to optimize this embodiment. Because of the flexibility of module  24  through buss  28 , software program  27  may be updated at any time to incorporate and take advantage of new understandings of fluorescent light filter wavelength interactions. 
         [0025]    The dichroic mirror  60  is the optical element that separates the excitation light  67  from light source  32  from the fluorescence return light  68 . Dichroic mirrors are special mirrors that reflect only a specific wavelength of light and are well known in prior art. They allow all other wavelengths to pass through. Dichroic mirrors used in fluorescence microscope filter blocks are typically placed in a forty-five degree incidence angle to light, creating a “stop band” of reflected light and a “pass band” of transmitted light. Light passing through said excitation filter may be reflected ninety degrees toward an objective lens  64  and a specimen containing a fluorophore  65 . Light emanating from a fluorophore  65  is then passed through and directed toward the optical output of a microscope  40 . The lookup table software  70  may incorporate a virtually unlimited range of excitation/barrier filter combinations. 
         [0026]    Barrier filters are optical elements that separate fluorescence emanating from a fluorophore  65  from other background light. A barrier filter panel  21 /guide  23  combination may transmit light of the fluorescence wavelength which passes through the dichroic mirror  60  while blocking all other light leaking from the excitation lamp light source  32 —reflected from the specimen or optical elements. This is necessary because the strength of the fluorescent light from a fluorophore is weaker than the excitation light by a factor that can exceed 100,000:1. As shown in  FIG. 2 , the software program  27  includes fluorescent filter optimizing look-up tables  70  which may incorporate all variables currently known, and those that may be later discovered, that apply to excitation and barrier filter combinations. 
         [0027]    Software programs  26  and  27  incorporate “color picker” software to output all wavelengths of light or color combinations available within the limits of said module  24  and said panels  20  and  21 . User interface  34  is provided to scroll through any or all of said available wavelength of light or colors and use button  36  to “lock in” the wavelength of light or colors of choice. 
         [0028]    A video monitor  30 , which may be a typical compact LCD or equivalent, black and white or color display of the type commonly used in computer monitors, laptop computers, or cellular phones, is electrically interfaced to a video driver circuit  19 , which is in turn electrically interfaced to, and controlled by module  24 . User interface  34  can be a mouse, joystick, or any other device which is interfaced to module  24  through buss  28  to enable selection of a wavelength of light or color in module  24 , the code for which is integrated into program  26 , and said wavelength of light or color being presented to a user on said display  30 . 
         [0029]    User interface  34  incorporates at least one simple switch or button  36  to “lock in” said wavelength of light or color selection in said program  27  for purposes of display on said panel  20  and said monitor  30 . Module  24  may provide video signals to circuit  19  so that the image and colors shown to a user are different, or substantially identical on display  30  and panel  20 . 
         [0030]    Light path guide  38  can be an air space, mirrors, a simple hollow coupler, a fiber optic cable, or any other means capable of conducting the light output of panel  20  toward an objective lens  64  in a viewing device  40 . Light guide  38  may or may not incorporate a collimating lens  39 . Device  40  in most cases will be a microscope, but can also be any other device which can benefit from the use of filtered light. 
         [0031]    Many of the components incorporated into the present invention such as microprocessors, video monitors, input devices and color generation software packages are in such widespread use that it is not necessary to detail them herein. It is hereby noted that the disclosed embodiments of the present invention herein do not necessarily exhibit all of the advantages of the present invention.