Systems and methods for irradiating tissue - Patents.com

Abstract

The present invention discloses a tissue illumination system 700. The tissue illumination system 700 comprises at least one radiation source 702 configured to generate a first radiation in a first wavelength band with a peak wavelength λ1 and at a first intensity, and a second radiation in a second wavelength band with a peak wavelength λ2 and at a second intensity, the intensity ratio of the first intensity to the second intensity being between 0.2 and 1, and the peak wavelength λ1 of the first wavelength band and the peak wavelength λ2 of the second wavelength band being [0025] The optical filter system 700 is selected to satisfy the relationship shown in TIFF2024521948000028.tif4386. The tissue illumination system 700 also includes a radiation light delivery unit 404 configured to deliver the first radiation light and the second radiation light toward the tissue of the target. Optical filter systems, devices, methods of illuminating tissue, and computer program products are also disclosed.

Description

[Technical field]

[0001] The present invention relates to systems and methods for illuminating tissue, and more particularly to systems and methods for illuminating tissue with radiation in two distinct wavelength bands or filtering radiation into two distinct wavelength bands. [Background technology]

[0002] Many personal care activities and skin measurement and monitoring activities involve a person observing or inspecting their own skin or the skin of another person. For example, a person may observe their own reflection in a mirror or an image of their face or body on the screen of a computing device (e.g., a tablet computer) or an imaging device (e.g., a camera) while performing a personal care activity, such as applying makeup. Similarly, a medical professional may inspect another person's skin when assessing that person for injury or illness, such as a bruise or inflammation of a body part.

[0003] The human eye may have difficulty clearly distinguishing between inflamed and non-inflamed tissue under broadband light (e.g., white light). The reason that the human eye cannot clearly identify the boundary between inflamed and non-inflamed areas of tissue is due to the fact that the spectral signatures of these distinct tissue areas are averaged and smoothed by broadband light. This, combined with the broad spectral properties of the L, M, and S cones of the human retina, reduces the contrast between inflamed and non-inflamed areas of tissue when broadband light is used. Summary of the Invention [Problem to be solved by the invention]

[0004] Therefore, there is a need for a system that enables the human eye to more clearly distinguish between inflamed and non-inflamed areas of tissue. [Means for solving the problem]

[0005] It would be beneficial to be able to better distinguish between inflamed and non-inflamed areas of tissue. This would allow bruises, rashes, and other lesions and inflammation of the skin or tissue to be better visualized. The inventors have recognized that such areas can be more easily distinguished from one another using a combination of light having certain characteristics. For example, they have recognized that blood-rich areas of tissue (e.g., lips, inflamed rashes or pimples, and irritated areas of the skin) appear redder when illuminated with a combination of green and red light. Inflamed and non-inflamed areas can be further distinguished by using a combination of radiation in specific wavelength bands, or broadband radiation that has been filtered to retain a combination of radiation in specific wavelength bands.

[0006] According to a first aspect, the present invention provides a tissue irradiation system comprising at least one radiation source configured to generate a first radiation light in a first wavelength band with a peak wavelength λ1 and at a first intensity and a second radiation light in a second wavelength band with a peak wavelength λ2 and at a second intensity; and a radiation delivery unit configured to deliver the first radiation light and the second radiation light towards tissue of a target, wherein an intensity ratio of the first intensity to the second intensity is between 0.2 and 1, and the peak wavelength λ1 of the first wavelength band and the peak wavelength λ2 of the second wavelength band are selected to satisfy the following relationship:

number

[0007] When the generated radiation (e.g., the first radiation and the second radiation) are used to illuminate inflamed and non-inflamed areas of tissue of a subject, the contrast between these tissue areas is enhanced, thereby allowing a subject observer to more clearly see the differences between the different areas. It is more difficult for a human observer to distinguish between inflamed and non-inflamed tissue areas under white light / broadband radiation.

[0008] In some embodiments, the first radiation and the second radiation each have a spectral full width at half maximum between 40 nm and 150 nm.

[0009] In some embodiments, the tissue illumination system further comprises a polarizer that linearly polarizes the radiation after it is emitted from the at least one radiation source or after it is reflected from the tissue of the target. In some embodiments, the tissue illumination system comprises a first polarizer that linearly polarizes the radiation after it is emitted from the at least one radiation source and a second polarizer that linearly polarizes the radiation reflected from the tissue of the target in a direction perpendicular to the polarization direction of the first polarizer.

[0010] In some embodiments, the tissue illumination system further comprises one or more sensors configured to measure a light intensity and / or a color temperature of ambient light at or near the tissue of interest. The tissue illumination system further comprises a processor operably coupled to the at least one radiation light source. The processor is configured to adjust, based on an output of the one or more sensors, one or both of an intensity of the radiation light generated by the at least one radiation light source and an intensity ratio of the first intensity to the second intensity.

[0011] The tissue illumination system further comprises an image capture device configured to receive emitted light reflected from the tissue of the target.

[0012] According to a second aspect, the present invention provides an optical filter system comprising at least one bandpass filter configured to transmit a first radiation in a first wavelength band, having a peak wavelength λ1, and at a first intensity, and a second radiation in a second wavelength band, having a peak wavelength λ2, and at a second intensity, wherein the at least one bandpass filter is configured to transmit the first radiation and the second radiation such that an intensity ratio of the first intensity to the second intensity is between 0.2 and 1, and the peak wavelength λ1 of the first wavelength band and the peak wavelength λ2 of the second wavelength band are selected to satisfy the following relationship:

number

[0013] In some embodiments, the at least one bandpass filter is configured to transmit the first radiation and the second radiation, such that the first radiation and the second radiation each have a spectral full width at half maximum between 40 nm and 150 nm.

[0014] According to a third aspect, the present invention provides a device comprising a tissue illumination system comprising at least one broadband radiation source configured to generate broadband radiation comprising a first radiation having a wavelength λ1 and a second radiation having a peak wavelength λ2. The device further comprises a radiation delivery unit configured to deliver the broadband radiation to tissue of a subject and an optical filter system as discussed above.

[0015] The optical filter system is positioned to filter the broadband radiation after it is emitted from the at least one radiation source and before it is reflected from tissue of the subject, or to filter the broadband radiation after it is reflected from tissue of the subject.

[0016] The device may include a medical instrument, a mirror, a headset, or a mask.

[0017] According to a fourth aspect, the present invention provides a method of irradiating tissue, comprising the steps of generating a first radiation in a first wavelength band having a peak wavelength λ1 and at a first intensity, generating a second radiation in a second wavelength band having a peak wavelength λ2 and at a second intensity, and transmitting the first radiation and the second radiation towards tissue of a target, wherein an intensity ratio of the second intensity to the first intensity is between 0.2 and 1, and the peak wavelength λ1 of the first wavelength band and the peak wavelength λ2 of the second wavelength band are selected to satisfy the following relationship:

number

[0018] In some embodiments, the method for irradiating tissue further comprises measuring one or both of a light intensity and a color temperature of ambient light at or near the tissue of interest, and adjusting one or both of an intensity of the first emitted light and / or a second emitted light and an intensity ratio of the first intensity to the second intensity based on the measured light intensity and / or the measured color temperature.

[0019] According to a fifth aspect, the present invention provides a computer program product comprising a non-transitory computer readable medium having computer readable code embodied therein which, when executed by a suitable computer or processor, configures the computer or processor to operate at least one light source to generate a first radiation in a first wavelength band having a peak wavelength λ1 and to be delivered to tissue of a subject at a first intensity, and to operate the at least one light source to generate a second radiation in a second wavelength band having a peak wavelength λ2 and to be delivered to tissue of the subject at a second intensity, wherein an intensity ratio of the first intensity to the second intensity is between 0.2 and 1, and wherein the peak wavelength λ1 of the first wavelength band and the peak wavelength λ2 of the second wavelength band are selected to satisfy the following relationship:

number

[0020] The first radiation and the second radiation each have a spectral full width at half maximum between 40 nm and 150 nm.

[0021] The computer readable code, when executed by a suitable computer or processor, is further configured to cause the computer or processor to receive sensor data indicative of the light intensity and / or color temperature of ambient light at or near the tissue of the subject, and to adjust one or both of the intensity of the emitted light generated by the at least one emitting light source and the intensity ratio of the first intensity to the second intensity based on the received sensor data.

[0022] These and other aspects of the invention will be apparent from and elucidated with reference to the embodiment(s) described hereinafter.

[0023] For a better understanding of the present invention, and to show more clearly how the same may be carried into effect, reference will now be made, by way of example only, to the accompanying drawings in which: [Brief description of the drawings]

[0024] [Figure 1] 1 is a series of graphs showing the visual contrast between inflamed and non-inflamed tissue areas when illuminated using white light and bi-color illumination. [Diagram 2] 1 is a series of graphs showing perceived color difference and perceived contrast for two different wavelengths of emitted light. [Diagram 3] 1 is a series of graphs illustrating various properties of emitted light at various intensity ratios. [Figure 4] 4 is a chart showing the data from FIG. 3 replotted for various ratio values. [Diagram 5] 1 is a graph of the A value as a function of the intensity ratio r. [Figure 6]5 is a chart showing the chart of FIG. 4 with areas indicating points that fall within a given parameter range. [Figure 7] FIG. 1 is a schematic diagram of an example of a tissue irradiation system. [Figure 8] FIG. 2 is a schematic diagram of another example of a tissue irradiation system. [Figure 9] FIG. 1 is a schematic diagram of an example tissue illumination system irradiating an area of ​​inflamed tissue. [Figure 10] FIG. 1 is a schematic diagram of an example tissue illumination system irradiating an area of ​​inflamed tissue. [Figure 11] FIG. 1 is a schematic diagram of an example optical filter system. [Figure 12] 1 is a flow diagram of an example method for irradiating tissue. [Figure 13] 1 is a schematic diagram of a processor in communication with a computer-readable medium. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] The embodiments disclosed herein provide a mechanism by which inflamed tissue may be more easily distinguished from non-inflamed or mildly inflamed tissue by a human observer. Under white or broadband light, such distinction is made more difficult due to the manner in which such light is reflected from tissue and received by the photoreceptors of the human eye. However, using the systems and methods disclosed herein, it is possible to clearly distinguish between these types of tissue. As used herein, the term "tissue" is intended to refer to any portion of human or animal body tissue, such as skin.

[0026] The inventors of the present disclosure have recognized that a combination of specific wavelength bands of emitted light may be particularly useful for those wishing to be able to distinguish between areas of inflamed tissue (e.g., blood-rich tissue) and areas of non-inflamed tissue. Through several simulations, the inventors have been able to determine specific wavelength bands of emitted light that, when combined, enhance the contrast between inflamed and non-inflamed areas of tissue. Graphs illustrating the results of various simulations are shown in Figures 1-3.

[0027] FIG. 1 is a series of graphs showing the visual contrast between inflamed and non-inflamed tissue regions when illuminated using white light (e.g., broadband light) and two-color radiation. FIG. 1a is a graph 100 showing the relative intensities of the white light 102 and two-color radiation 104 used during the simulation. The white light 102 has a constant relative intensity for all visible wavelengths, while the intensity of the two-color radiation peaks at red and green wavelengths. The two-color radiation specifically included radiation having a first peak wavelength of 680 nanometers (nm) and a full width at half maximum (FWHM) of 80 nm, and radiation having a second peak wavelength of 490 nm and a FWHM of 80 nm. The intensity ratio of the two-color radiation used in the simulation was 0.5:1 (i.e., the radiation having a peak wavelength of 490 nm was prepared at twice the intensity of the radiation having a peak wavelength of 680 nm). In the simulation, two types of synchrotron radiation were used to illuminate two regions of tissue: an area of ​​normal, non-inflamed tissue, and an area of ​​inflamed tissue.

[0028] FIG. 1b is a graph 110 showing the observed results of two different tissue regions, expressed numerically using color-matching functions defined by the International Commission on Illumination (CIE).

number

number

number

[0029] 1c and 1d show graphs 120 and 130 of reflectance spectra for inflamed and non-inflamed tissue regions, respectively, under white light (FIG. 1c) and bi-color radiation (FIG. 1d). In graph 120, line 122 represents the reflectance from the non-inflamed tissue region, and line 124 represents the reflectance from the inflamed tissue region. In graph 130, line 132 represents the reflectance from the non-inflamed tissue region, and line 134 represents the reflectance from the inflamed tissue region. FIGs. 1e and 1f show graphs 140 and 150 of the corresponding tristimulus values, respectively, under white light (FIG. 1e) and bi-color radiation (FIG. 1f). In graph 140, data bar 142 represents the tristimulus values ​​for the non-inflamed tissue region, and data bar 144 represents the tristimulus values ​​for the inflamed tissue region. In graph 150, data bar 152 represents the tristimulus values ​​for the non-inflamed tissue area, and data bar 154 represents the tristimulus values ​​for the inflamed tissue area. From the tristimulus values ​​shown in graphs 140 and 150, it can be observed that the difference in the relative ratios of X, Y, and Z values ​​of the reflection from the inflamed tissue area and the reflection from the non-inflamed tissue area is greater when using dichromatic radiation than when using white light. This difference in the relative ratios can be quantified by calculating the resulting color difference or distance metric between the inflamed and non-inflamed tissue areas.

[0030] Figure 2 is a series of contour plots showing the perceived color difference and the perceived contrast between inflamed and non-inflamed tissue areas for combinations of different peak wavelengths of two light sources with equal intensity and equal spectral width (FWHM) of 80 nm. Figure 2a shows a contour plot 200 of the perceived contrast calculated with respect to lightness L, Figure 2b shows a contour plot 210 of the perceived contrast calculated with respect to hue H, Figure 2c shows a contour plot 220 of the perceived contrast calculated with respect to chroma C, and Figure 2d shows a contour plot 230 of the calculated perceived total contrast (denoted delta E or dE94 by the standard CIE 1994). In Figure 2, "Emission Band A" corresponds to the wavelengths of the first emission band (wavelengths in the red part of the visible spectrum) and "Emission Band B" corresponds to the wavelengths of the second emission band (wavelengths in the green part of the visible spectrum). The dotted lines shown in the plot of Figure 2 represent contour lines corresponding to the contrast between inflamed and non-inflamed tissue regions when illuminated with white radiation. It is clear from the plot 230 of Figure 2d that the perceived total contrast between inflamed and non-inflamed tissue regions is greater when using bichromatic radiation with peak wavelengths at 490 nm and 680 nm compared to white radiation.

[0031] FIG. 3 is a series of plots showing how the relative contrast varies as a function of the spectral width (i.e., FWHM). FIG. 3a shows a plot 300 of the relative contrast improvement as a function of FWHM for various intensity ratios. FIG. 3b shows a plot 310 of the wavelength of the first emission band (i.e., "emission band A", wavelengths in the red portion of the visible spectrum) as a function of FWHM for various intensity ratios, and FIG. 3c shows a plot 320 of the wavelength of the second emission band (i.e., "emission band B", wavelengths in the green portion of the visible spectrum) as a function of FWHM for various intensity ratios. From the plot 300 of FIG. 3a, it is clear that the relative contrast improvement peaks when the spectral bandwidth is about 80 nm. The plot 300 also shows that the optimal intensity ratio is 0.5, and that significant contrast improvement can also be seen when intensity ratios of 0.2 and 1 are used. As the intensity ratio decreases below 0.1 or increases above 2, the relative contrast improvement becomes smaller. Thus, an intensity ratio between 0.2 and 1 provides optimal contrast improvement.

[0032] Based on the results of various simulations, it is possible to determine the range of peak wavelengths, the range of spectral widths, and the optimal intensity ratio that results in an improvement in contrast between inflamed and non-inflamed tissue regions. Table 1 below summarizes the optimal parameter ranges for the two emission bands that result in an improvement in contrast of more than 30%.

[0033] [Table 1]

[0034] 4 is a chart 400 showing the data from Figures 3b and 3c replotted for various ratio values ​​r. The data is fitted to the following rational function:

number

[0035] [Table 2]

[0036] Replacing the variable y with λ2 and the variable x with λ1, we get the following. A=(λ1-594nm)(λ2-425nm) (Formula 1)

[0037] 5 is a chart 500 showing values ​​of A from Table 2 above plotted as a function of the ratio value r for each value of A. In chart 500, a curve fitted to the data fits the following function: A = c(1-e -r / t ) (Formula 2) Here the fitted values ​​are c=8009±176 and t=0.2738±0.0161. Combining equations 1 and 2 gives: c(1-e -r / t )=(λ1-594nm)(λ2-425nm) (Equation 3)

number

[0038] Equation 5 relates a peak wavelength λ1 in a first wavelength band (e.g., 640 nm to 720 nm), a peak wavelength λ2 in a second wavelength band (e.g., 470 nm to 530 nm), and a relative intensity ratio r between λ1 and λ2. Thus, equation 5 can be used to determine the intensity ratio r given the peak wavelengths λ1 and λ2 of the first and second wavelength bands, respectively. It is believed that a combination of λ1, λ2, and r provides good contrast between inflamed and non-inflamed tissue regions when the relative intensity ratio r is in the range of 0.2 to 1.

[0039] Figure 6 shows the chart 400 of Figure 4 including an additional region 600 indicated by a dashed line. Data points falling within region 600 have parameters λ1 that is in the wavelength band of interest from 640 nm to 740 nm, λ2 that is in the wavelength band of interest from 470 nm to 530 nm, and r that is in the intensity ratio range of interest from 0.2 to 1. Points falling within region 600 thus correspond to radiation that illuminates a tissue region such that the human eye sees good contrast between inflamed and non-inflamed regions of the tissue.

[0040] The coverage of the first and second wavelength bands can be expressed independently of the intensity ratio. From Table 2 above, when r=0.2, A=3816, and when r=1, A=7694. This can be expressed as follows: 0.2≦r≦1, and 3816≦A≦7694 Substituting this into equation 1 gives the following: 3816≦(λ1-594nm)(λ2-425nm)≦7694

[0041] Combining all the inequalities, the operating ranges of the first and second wavelength bands can be expressed as follows:

number

[0042] The last two relations define the wavelength range of the first peak wavelength λ1 as a function of the second peak wavelength λ2.

[0043] Thus, various embodiments disclosed herein use emitted light having parameters including a first peak wavelength in the range of 640 nm to 740 nm, a second peak wavelength in the range of 470 nm to 530 nm, and an intensity ratio of the emitted light at the second peak wavelength to the emitted light at the first peak wavelength in the range of 0.2 to 1. Within these ranges, the first peak wavelength falls within the ranges given below.

number

number

[0044] The emitted light has a spectral width (e.g., FWHM) in the range of 40 nm to 150 nm. In other embodiments, the emitted light has a spectral width (e.g., FWHM) outside of this range and still provides good contrast between inflamed and non-inflamed tissue.

[0045] The radiation having the above-specified parameters is delivered to the skin or tissue of the subject using the tissue illumination system disclosed herein. Alternatively, white or broadband radiation is delivered to the skin or tissue of the subject, and the radiation incident on or reflected from the skin or tissue is filtered using one or more filters, such that the radiation observed by the observer has one or more of the above-specified parameters. Examples of various systems used to observe the tissue of a subject being illuminated using radiation having the above-specified parameters are discussed below.

[0046] Figure 7 is a schematic diagram of one example of a tissue illumination system 700, and Figure 8 is a schematic diagram of another example of a tissue illumination system 800. The tissue illumination systems 700, 800 comprise at least one radiation light source 702 and a radiation light delivery unit 704. In the embodiment shown in Figure 7, the tissue illumination system 700 comprises a single radiation light source 702, whereas in the embodiment shown in Figure 8, the tissue illumination system 800 comprises two radiation light sources 702a and 702b. In other examples, more radiation light sources are provided.

[0047] In the tissue illumination system 700, the radiation source 702 is configured to generate a first radiation in a first wavelength band at a first intensity, the first radiation having a peak wavelength λ1. The peak wavelength of the first radiation is between 640 nm and 740 nm, and the first radiation has a full width at half maximum of the spectrum between 40 nm and 150 nm. The at least one radiation source 702 is also configured to generate a second radiation in a second wavelength band at a second intensity, the second radiation having a peak wavelength λ2. The peak wavelength of the second radiation is between 470 nm and 530 nm, and the second radiation has a full width at half maximum of the spectrum between 40 nm and 150 nm. The peak wavelength λ1 of the first wavelength band and the peak wavelength λ2 of the second wavelength band are selected to satisfy the following relationship:

number

[0048] In some examples, the radiation source 702 generates multi-band broadband radiation including a first radiation and a second radiation, while in other examples, the radiation source 702 generates radiation in two distinct wavelength bands having the parameters mentioned above.

[0049] In the tissue illumination system 800, the multiple radiation sources 702a, 702b are each configured to generate radiation in a different wavelength band, for example, radiation source 702a is configured to generate a first radiation in a first wavelength band at a first intensity (e.g., having corresponding parameters as mentioned above) and radiation source 702b is configured to generate a second radiation in a second wavelength band at a second intensity (e.g., having corresponding parameters as mentioned above).

[0050] The radiation light delivery unit 704 is configured to deliver the first radiation light and the second radiation light toward tissue of a subject. The subject includes a person (i.e., a human) undergoing an examination, for example, as part of a medical checkup or as part of a personal care or hygiene routine, or viewing an image or reflection of their own head or body when performing a self-examination for medical reasons or as part of a personal care routine. In other examples, the subject includes an animal. As discussed above, when the tissue of the subject is viewed under radiation light having the parameters specified above (i.e., under a combination of the first radiation light and the second radiation light), it is possible to more clearly distinguish between inflamed and non-inflamed tissue regions.

[0051] The radiation light delivery unit 704 is in optical communication with the at least one radiation light source 702 such that the radiation light generated by the radiation light source can be delivered towards the tissue of interest. To achieve this, the radiation light delivery unit 704 comprises one or more optical elements.

[0052] 9 is a schematic diagram of an example of a tissue illumination system 700 in use. Radiated light (i.e., a first radiation light and a second radiation light) is generated by at least a radiation source 702 and directed via a radiation light delivery unit 704 towards a user's tissue 900. The tissue 900 includes, in this example, a non-inflamed area 902 and an inflamed area 904. The inflamed area 904 includes tissue having a relatively large amount of blood therein, such as a lip, a bruise, or a rash. The radiation light reflects from the tissue 900 towards the eye of an observer 906. For example, if an observer is looking at their own head or body in a mirror, or looking at an image of their own head or body on a computing device such as a tablet computer or smartphone, it will be understood that the observer 906 is the subject at which the tissue 900 is being observed. Alternatively, the observer 906 is a person at whom the tissue 900 is not being observed.

[0053] In some embodiments, the first and second emitted light are generated and / or emitted / transmitted to the tissue of the target with equal intensities. Thus, the intensity ratio of the second intensity to the first intensity is 1. However, in other embodiments, the second intensity is less than the first intensity, so that the second emitted light is generated, emitted or transmitted with an intensity less than that of the first emitted light. Thus, the intensity ratio of the first intensity to the second intensity is between 0.2 and 1. In other examples, the intensity ratio of the first intensity to the second intensity is between 0.4 and 0.6. More specifically, in some examples, a specific intensity ratio of 0.2, 0.5 or 1 is used. The intensity ratio is modified based on ambient light parameters, such as the ambient light intensity, as will become apparent below.

[0054] According to some embodiments, the tissue illumination system 700, 800 includes one or more other components, such as optical components, to enhance the contrast between inflamed and non-inflamed tissue regions. The tissue illumination system 700, 800 includes, for example, a diffuser configured to diffuse the radiation (e.g., light) emitted from the radiation source 702. The tissue illumination system 700, 800, in other examples, includes one or more polarizers configured to polarize the radiation (e.g., light) emitted from the radiation source 702. FIG. 10 is a schematic diagram of an example of the tissue illumination system 700 in use, including various optional components. As mentioned above, the tissue illumination system 700 includes, in some embodiments, a polarizer 1000 that linearly polarizes the radiation after it is emitted from the at least one radiation source 702 or after it is reflected from the tissue of interest, and thus the polarizer 1000 is positioned at one of several locations relative to the radiation source 702 and the observer 906. The polarizer 1000 is provided in a first position, as shown in FIG. 10, where the radiation emitted from the radiation delivery unit 704 passes through the polarizer before reaching the tissue of the target, or in a second position, where the radiation passes through the polarizer after reflecting from the tissue of the target. In some examples, multiple polarizers (e.g., two polarizers) are provided, configured to polarize light in mutually orthogonal directions to reduce specular reflection from the tissue. The tissue illumination system 700, 800 comprises, for example, a first polarizer that linearly polarizes the radiation after it is emitted from the at least one radiation source, and a second polarizer that linearly polarizes the radiation reflected from the tissue of the target in a direction perpendicular to the polarization direction of the first polarizer. In other words, the first polarizer linearly polarizes the radiation after it is emitted from the at least one radiation source in a first direction, and the second polarizer polarizes the radiation in a second direction orthogonal to the first direction.

[0055] The tissue illumination system 700 further comprises, in some embodiments, a processor 1002 and / or one or more sensors 1004. The one or more sensors 1004 are configured to measure the light intensity and / or color temperature of the ambient light at or near the tissue of interest. The one or more sensors 1004 comprise, for example, a photometer. The processor 1002 is operatively coupled to the at least one radiation source 702. The processor 1002 is configured to adjust a parameter of the radiation source or the radiation light emitted from the radiation source based on the output of the one or more sensors 1004. The processor 1002 is configured to adjust, for example, one or both of the intensity of the radiation light generated by the at least one radiation source and the intensity ratio of the first intensity to the second intensity based on the output of the one or more sensors 1004. In other embodiments, the processor 1002 is configured to adjust one or more other parameters in addition to the parameters mentioned above. By adjusting the parameters based on measurements recorded using the one or more sensors 1004, the emitted light delivered towards the tissue of interest can be adjusted according to ambient conditions to further enhance the contrast between inflamed and non-inflamed tissue regions. The one or more sensors 1004 may detect high ambient luminance, for example, in bright sunlight, and thus the intensity of the emitted light generated by the emitted light source 702 may be increased accordingly. The one or more sensors may, in some examples, be configured to measure the intensity of the emitted light in each wavelength band (e.g., a red wavelength band and a green wavelength band) separately, and the processor 1002 may be configured to adjust the intensity of the emitted light generated in one or both wavelength bands separately.

[0056] The tissue illumination system 700 further comprises, in some embodiments, an image capture device 1006 configured to receive the radiation reflected from the tissue of interest. The image capture device 1006 comprises, for example, a charge-coupled device (CCD) or a camera capable of capturing a single image or a series of images (e.g., video footage). In this manner, one or more images of the tissue of interest are recorded and subsequently reviewed. Because the tissue is illuminated using radiation of two distinct wavelength bands, the contrast between inflamed and non-inflamed areas of the tissue is distinguishable in the captured images.

[0057] The tissue illumination system 700, 800 includes a single apparatus or device in which the various components discussed herein form part of a single integrated unit. However, in other embodiments, the various components form part of a distributed system, as shown in FIG. 10. One or more of the components of the tissue illumination system 700 discussed herein may form part of a mirror or smart mirror that a user uses to observe their face or body. Such a mirror may include, for example, a radiation source 702, a radiation light delivery unit 704, a polarizer 1000, a processor 1002, one or more sensors 1004, and / or an image capture device 1006.

[0058] As discussed above, the contrast between inflamed and non-inflamed tissue regions is enhanced by illuminating the tissue with emitted light having the specific range of characteristics discussed herein. In particular, it has been found that a combination of emitted light within the red and green wavelength bands provides a particularly high contrast between inflamed and non-inflamed tissue regions. Also, as mentioned above, visual contrast is enhanced by filtering the broadband emitted light (e.g., white light) using a filter system to substantially filter out emitted light outside the red and green wavelength bands or to filter out emitted light that does not have the specific characteristics discussed herein. Thus, in some embodiments, the at least one emitted light source includes a broadband emitted light source configured to generate broadband emitted light including a first emitted light and a second emitted light. In other words, the broadband emitted light source generates white light including light within the specific wavelength bands discussed herein. In such an embodiment, the emitted light delivery unit 704 is configured to deliver broadband emitted light to the tissue of the target. The tissue illumination system 700 further comprises at least one filter configured to filter the broadband radiation to filter out radiation having a wavelength outside the first wavelength band and radiation having a wavelength outside the second wavelength band. Specifically, the at least one filter is configured to filter the broadband radiation to transmit a first radiation in a first wavelength band with a first intensity, the first radiation having a peak wavelength between 640 nm and 740 nm, and transmit a second radiation in a second wavelength band with a second intensity, the second radiation having a peak wavelength between 470 nm and 530 nm. The first and second radiation have a full width at half maximum spectrum between 40 nm and 150 nm. In some examples, a single filter is used, while in other examples, two or more filters are used to enable appropriate filtering of the broadband radiation. Thus, the at least one filter includes at least one bandpass filter.

[0059] Such optical filters are characterized, for example, by the filter's spectral transmission band (i.e., the range of wavelengths transmitted) and the filter's spectral transmittance (i.e., the amount (e.g., percentage) of radiation light that is transmitted). Thus, a broadband radiation source is filtered by an optical filter configured to transmit radiation in two spectral bands (e.g., using a dual bandpass filter). Each spectral band is transmitted with a distinct transmittance value such that radiation transmitted from a first spectral band of the optical filter with the first optical transmittance has a first intensity, and radiation transmitted from a second spectral band of the optical filter with the second optical transmittance has a second intensity.

[0060] According to a further aspect, the present invention provides an optical filter system. FIG. 11 is a schematic diagram of an example of an optical filter system 1100 used to improve contrast between non-inflamed and inflamed tissue areas of a subject. The optical filter system 1100 comprises at least one band-pass filter 1102. The at least one band-pass filter 1102 is configured to allow transmission of a first radiation light of a first wavelength band having a peak wavelength λ1 and at a first intensity, and to allow transmission of a second radiation light of a second wavelength band having a peak wavelength λ2 and at a second intensity. The at least one band-pass filter (1102) is configured to allow transmission of the first radiation light and the second radiation light such that an intensity ratio of the first intensity to the second intensity is between 0.2 and 1. The peak wavelength λ1 of the first wavelength band and the peak wavelength λ2 of the second wavelength band are selected to satisfy the following relationship:

number

[0061] At least one bandpass filter (1102) is configured to transmit the first and second emitted light, in some examples, such that the first and second emitted light have a full width at half maximum spectrum between 40 nm and 150 nm, respectively. In some examples, multiple bandpass filters are provided, for example, a first bandpass filter that allows transmission of the first emitted light and a second bandpass filter that allows transmission of the second emitted light. In use, the tissue of interest is illuminated using broadband emitted light (e.g., white light), and the optical filter system 1100 limits the emitted light that is transmitted through the filter system such that an observer of the tissue can observe inflamed and non-inflamed areas of the tissue with high contrast when using the optical filter system.

[0062] In some embodiments, the optical filter system 1100 comprises a radiation source, such as a broadband radiation source or a white light source, and directs radiation towards the tissue. The radiation reflected from the tissue passes through the optical filter system 1100, resulting in filtered radiation reaching the observer's eye. The optical filter system 1100 is constructed and / or arranged to spectrally filter the radiation after it is emitted from the radiation source or to spectrally filter radiation reflected from the tissue of the subject.

[0063] In some embodiments, the at least one bandpass filter 1102 is configured to allow transmission of the first emitted light and the second emitted light such that an intensity ratio of the second intensity to the first intensity is between 0.2 and 1.

[0064] The optical filter system 1100 comprises or forms part of a device or apparatus used by the subject or an observer of the subject. The present invention thus provides, according to a further aspect, a device comprising the tissue illumination system 700, 800 disclosed herein or the optical filter system 1100 disclosed herein. In some embodiments, the device comprises a medical instrument, a mirror (e.g., a smart mirror), a headset (e.g., smart glasses), or a mask. Such a device is worn by an observer of the subject or by the subject himself. The device comprises, in one example, a magnifying device or an optical relay device incorporated as a scope for observing tissue in an opening of the subject, such as the nostril, the mouth, or the ear canal. Such a device incorporates the tissue illumination system 700, 800 or the optical filter system 1100 disclosed herein to enable the user of the device to identify inflamed tissue.

[0065] According to a further aspect, the present invention provides a method for irradiating tissue. FIG. 12 is a flow diagram of an example of a method 1200, such as a method for irradiating tissue. The method 1200 may be performed, for example, using the tissue irradiating system 700, 800 disclosed herein. The method 1200 includes, at step 1202, generating a first radiation in a first wavelength band having a peak wavelength λ1 and at a first intensity. The method 1200 includes, at step 1204, generating a second radiation in a second wavelength band having a peak wavelength λ2 and at a second intensity. The intensity ratio of the first intensity to the second intensity is between 0.2 and 1, and the peak wavelength λ1 of the first wavelength band and the peak wavelength λ2 of the second wavelength band are selected to satisfy the following relationship:

number

[0066] The method 1200 includes transmitting a first emitted light and a second emitted light toward tissue of a target at step 1206. The transmitted emitted light is then observed by an observer, where the combination of the first emitted light and the second emitted light enhances the contrast between inflamed and non-inflamed areas of the tissue, allowing the observer to better distinguish between such areas.

[0067] Method 1200, in some embodiments, further comprises measuring one or both of the light intensity and color temperature of ambient light at or near the tissue of interest. Method 1200 further comprises adjusting one or both of the intensity of the first emitted light and / or the second emitted light and the intensity ratio of the first intensity to the second intensity based on the measured light intensity and / or the measured color temperature. In this way, regions of the tissue of interest, and in particular the contrast between such regions, become even more clearly distinguishable to the observer.

[0068] In some embodiments, the method 1200 further comprises capturing an image of the tissue of interest after the emitted light has reflected from the tissue, such that an image of the user's tissue can be subsequently viewed by an observer to capture improved contrast between inflamed and non-inflamed areas of the tissue.

[0069] In some embodiments, the at least one radiation source includes a broadband radiation source configured to generate broadband radiation, the broadband radiation including radiation in a first wavelength band and radiation in a second wavelength band. In such embodiments, transmitting the radiation comprises transmitting the broadband radiation toward tissue of the target. The method further comprises filtering the broadband radiation to filter out radiation having wavelengths outside the first wavelength band and radiation having wavelengths outside the second wavelength band. More specifically, the method further comprises filtering the broadband radiation to allow transmission of a first radiation in a first wavelength band with a peak wavelength between 640 nm and 740 nm and at a first intensity, and a second radiation in a second wavelength band with a peak wavelength between 470 nm and 530 nm and at a second intensity. In some embodiments, the method comprises filtering the broadband radiation to allow transmission of the first radiation and the second radiation having a spectral full width at half maximum between 40 nm and 150 nm.

[0070] According to a further aspect, the present invention provides a computer program product. Figure 13 is a schematic diagram of an example of a processor 1302 in communication with a computer readable medium 1304. In various embodiments, the computer program product comprises a non-transitory computer readable medium 1304 having computer readable code embodied therein, which, when executed by a suitable computer or processor 1302, configures the computer or processor to operate at least one light source to generate a first emitted light in a first wavelength band having a peak wavelength λ1 and at a first intensity to be delivered to the tissue of the target, and to operate at least one light source to generate a second emitted light in a second wavelength band having a peak wavelength λ2 and at a second intensity to be delivered to the tissue of the target. The intensity ratio of the first intensity to the second intensity is between 0.2 and 1. The peak wavelength λ1 of the first wavelength band and the peak wavelength λ2 of the second wavelength band are selected to satisfy the following relationship:

number

[0071] The first emitted light and the second emitted light each have a spectral full width at half maximum between 40 nm and 150 nm. More generally, the computer readable code, when executed by a processor 1302, configures the processor to perform one or more steps of the method 1200 disclosed herein. The processor 1302 includes the processor 1002 discussed above.

[0072] In some embodiments, the computer readable code, when executed by a suitable computer or processor 1302, is further configured to cause the computer or processor to receive sensor data indicative of the light intensity and / or color temperature of ambient light at or near the tissue of interest, and adjust one or both of the intensity of the emitted light generated by the at least one emitting light source and the intensity ratio of the second intensity to the first intensity based on the received sensor data. The sensor data may include, for example, data obtained and / or received from one or more sensors 1004 discussed above.

[0073] The processor 1002, 1302 may include one or more processors, processing units, multi-core processors or modules configured or programmed to control components of the systems 700, 800 in the manner described herein. In certain implementations, the processor 1002, 1302 may comprise multiple software and / or hardware modules, each configured to perform or for performing individual or multiple steps of the methods described herein.

[0074] The term "module" as used herein is intended to include a hardware component, such as a processor or a component of a processor configured to perform a particular function, or a software component, such as a set of instruction data that has a particular function when executed by a processor.

[0075] It will be understood that the embodiments of the present invention also apply to a computer program adapted to implement the present invention, in particular a computer program on or in a carrier. The program may be in the form of object code, such as source code, object code, code intermediate source and partially compiled form, or in any other form suitable for use in implementing the method according to the embodiments of the present invention. It will also be understood that such a program may have many different architectural designs. For example, the program code implementing the functions of the method or system according to the present invention is subdivided into one or more subroutines. Many different ways of distributing functionality among these subroutines will be apparent to those skilled in the art. The subroutines are stored together in one executable file to form a self-contained program. Such an executable file comprises computer executable instructions, such as processor instructions and / or interpreter instructions (e.g. Java interpreter instructions). Alternatively, one or more or all of the subroutines are stored in at least one external library file and linked statically or dynamically, for example at run-time, with the main program. The main program includes at least one call to at least one of the subroutines. The subroutines also have function calls between each other. An embodiment relating to a computer program product has computer-executable instructions corresponding to each processing step of at least one of the methods described herein, the instructions being subdivided into subroutines and / or stored in one or more statically or dynamically linked files. Another embodiment relating to a computer program product has computer-executable instructions corresponding to each means of at least one of the systems and / or products described herein, the instructions being subdivided into subroutines and / or stored in one or more statically or dynamically linked files.

[0076] The carrier of a computer program is any entity or device capable of carrying the program. The carrier includes, for example, a data storage device, such as a ROM, for example a CD-ROM or a semiconductor ROM, or a magnetic recording medium, for example a hard disk. The carrier is also a transmissible carrier, such as an electric or optical signal conveyed via an electric or optical cable or by radio or other means. When the program is embodied in such a signal, the carrier is constituted by such a cable or other device or means. Alternatively, the carrier is an integrated circuit in which the program is embedded, the integrated circuit being adapted for or used in the performance of the method in question.

[0077] The present invention can also be described in terms of the following clauses. Clause 1 The tissue irradiation system (700, 800) includes: a first radiation having a peak wavelength λ1 and a first intensity and a first wavelength band; a second radiation having a peak wavelength λ2 and a second intensity and a second wavelength band; At least one radiation source (702) configured to generate a radiation delivery unit (404) configured to deliver a first radiation beam and a second radiation beam toward tissue of a target; an intensity ratio of the first intensity to the second intensity is between 0.2 and 1; and The peak wavelength λ1 of the first wavelength band and the peak wavelength λ2 of the second wavelength band are selected so as to satisfy the following relational expression.

number

number

number

number

[0078] Those skilled in the art can understand and produce variations to the disclosed embodiments from a study of the drawings, the disclosure, and the appended claims when practicing the claimed invention. In the claims, the word "comprises" does not exclude other elements or steps, nor does the singular element exclude a plurality. A single processor or other unit fulfills the functions of several items recited in the claims. The mere fact that certain means are recited in mutually different dependent claims does not indicate that a combination of these means cannot be used to advantage. The computer program may be stored / distributed on a suitable medium, such as an optical storage medium or a solid-state medium, provided integrally with or as part of other hardware, or distributed in other forms, such as via the Internet or other wired or wireless telecommunication systems. Any reference signs in the claims should not be interpreted as limiting the scope.

Claims

1. Peak wavelength λ １ a first radiation having a first intensity and a first wavelength band; Peak wavelength λ ２ a second radiation having a second intensity and a second wavelength band; At least one radiation source generating two-color radiation having a radiation delivery unit for delivering the first radiation and the second radiation toward tissue of a target; 1. A tissue irradiation system comprising: an intensity ratio of the first intensity to the second intensity is between 0.2 and 1; and The peak wavelength λ of the first wavelength band １ and the peak wavelength λ of the second wavelength band ２ And the relation is ##EQU00021## is selected to satisfy 11. A system for illuminating tissue, wherein the first radiation and the second radiation each have a spectral full width at half maximum between 40 nm and 150 nm.

2. 2. The tissue illumination system of claim 1, further comprising a polarizer that linearly polarizes the dichroic radiation after it is emitted from the at least one radiation source or after it is reflected from the tissue of the subject.

3. one or more sensors that measure light intensity and / or color temperature of ambient light at or near the tissue of the subject; a processor operably coupled to the at least one radiation source, the processor determining, based on an output of the one or more sensors, an intensity of radiation generated by the at least one radiation source; and the intensity ratio of the first intensity to the second intensity; and a processor and / or The tissue irradiation system according to claim 1 or 2, further comprising:

4. 4. The tissue irradiation system of claim 1, further comprising an image capture device for receiving emitted light reflected from the tissue of the subject.

5. Peak wavelength λ １ a first radiation having a first intensity and a first wavelength band; and a peak wavelength λ ２ and a second radiation in a second wavelength band at a second intensity, the at least one bandpass filter is capable of transmitting the first radiation and the second radiation such that an intensity ratio of the first intensity to the second intensity is between 0.2 and 1; and The peak wavelength λ of the first wavelength band １ and the peak wavelength λ of the second wavelength band ２ And the relation is [0022] is selected to satisfy the at least one bandpass filter can transmit the first radiation and the second radiation such that the first radiation and the second radiation each have a spectral full width at half maximum between 40 nm and 150 nm.

6. wavelength λ １ and a first synchrotron radiation having a peak wavelength λ ２ and a second radiation having a first wavelength of about 100 nm to about 150 nm; a radiation delivery unit for delivering the broadband radiation to tissue of a target; A tissue irradiation system comprising:

6. The optical filter system of claim 5, wherein the optical filter system is arranged to filter the broadband radiation after it is emitted from the at least one radiation source and before it is reflected from the tissue of the subject. A device comprising:

7. wavelength λ １ and a first synchrotron radiation having a peak wavelength λ ２ and a second radiation having a first wavelength of about 100 nm to about 150 nm; a radiation delivery unit for delivering the broadband radiation to tissue of a target; A tissue irradiation system comprising:

6. The optical filter system of claim 5, wherein the optical filter system is arranged to filter the broadband radiation after it is reflected from the tissue of the subject. A device comprising:

8. 10. A device, including a medical instrument, a mirror, a headset or a mask, comprising a tissue illumination system according to claims 1 to 4 or an optical filter system according to claim 5.

9. Peak wavelength λ １ generating a first radiation in a first wavelength band at a first intensity; Peak wavelength λ ２ generating a second radiation in a second wavelength band at a second intensity; transmitting the first radiation and the second radiation toward tissue of a target; 1. A method of irradiating tissue, comprising: an intensity ratio of the first intensity to the second intensity is between 0.2 and 1; and The peak wavelength λ of the first wavelength band １ and the peak wavelength λ of the second wavelength band ２ But the relation [0023] is selected to satisfy 20. The method of irradiating tissue, wherein the at least one bandpass filter is operable to transmit the first radiation and the second radiation such that the first radiation and the second radiation each have a spectral full width at half maximum between 40 nm and 150 nm.

10. measuring one or both of the light intensity and color temperature of ambient light at or near the tissue of the subject; adjusting one or both of an intensity of the first emitted light and / or the second emitted light and the intensity ratio of the first intensity to the second intensity based on the measured light intensity and / or the measured color temperature.

10. The method of claim 9, further comprising:

11. The method includes the steps of: providing a method for detecting a light source comprising: providing a light source configured to receive light from a light source and receiving the light from the light source; A peak wavelength, λ, to be delivered to the tissue of the target at a first intensity. １ a first radiation in a first wavelength band having a peak wavelength λ to be delivered to the tissue of the subject at a second intensity; ２ and a second radiation having a second wavelength band having generating two-color radiation, an intensity ratio of the first intensity to the second intensity is between 0.2 and 1; and The peak wavelength λ of the first wavelength band １ and the peak wavelength λ of the second wavelength band ２ And the relation is [0024] is selected to satisfy 11. The non-transitory computer readable medium, wherein the first radiation and the second radiation each have a spectral full width at half maximum between 40 nm and 150 nm.

12. The computer readable code may further be adapted, when executed by the preferred computer or processor, to cause the computer or processor to: receiving sensor data indicative of light intensity and / or color temperature of ambient light at or near the tissue of the subject; and Based on the received sensor data, the intensity of radiation generated by at least one of said radiation sources; and the intensity ratio of the first intensity to the second intensity; and Adjust one or both of the following: The non-transitory computer-readable medium of claim 11.

Images