Endoscope and lighting device thereof

Abstract

The invention relates to the technical field of lighting, in particular to an endoscope and a lighting device thereof. According to the lighting device, an LED light source is controlled by a light source controller to emit combined white light composed of purple light waves, blue light waves, green light waves and red light waves, the spectrum of the combined white light comprises a first wave crest and a second wave crest, the peak wavelength of the first wave crest is located in the wave band range of 400 nm to 430 nm, and the peak wavelength of the second wave crest is located in the wave band range of 400 nm to 430 nm. The wavelength range is overlapped with the wavelength range of the strongest light wave absorption peak of the blood oxygen protein in the blood vessel of the human tissue; the peak wavelength of the second peak in the combined white light spectrum is within the wave band range of 520-560 nm, and the wavelength range is overlapped with the wavelength range of the light wave secondary strong absorption peak of the blood oxygen protein in the blood vessel of the human tissue. Therefore, when endoscope imaging is carried out by adopting the scheme of the invention, the LED light source can enable the blood oxygen protein to realize higher response in each response channel of the RGB image sensor, so that the distinguishing degree of tissues containing blood oxygen protein and tissues not containing blood oxygen protein in an image is effectively improved.

Description

Technical Field

[0001] The present invention relates to the field of lighting technology, and in particular to an endoscope and a lighting device thereof. Background Art

[0002] As we all know, in order to perceive colors, conventional color imaging sensors use a filter system based on the principle of tristimulus values ​​in front of the sensor's photosensitive area to distinguish different colors to achieve color imaging. Therefore, the B color area of ​​a conventional image sensor using an RGB filter system (abbreviated as image sensor or RGB image sensor) represents the blue response channel, which has a higher response in the 380nm-520nm band; the G color area represents the green response channel, which has a higher response in the 460nm-610nm band; and the R color area represents the red response channel, which has a higher response in the 580nm-800nm ​​band.

[0003] At present, in order to pursue higher luminous efficiency, conventional white light LEDs for lighting usually use a combination of blue semiconductor light-emitting chips and a variety of phosphors. The emission spectrum of this combination of white light is in the 380nm-780nm band. Although the energy proportion of each wavelength in the emission spectrum is more in line with the spectral response characteristics of the human eye, it is impossible to achieve a high response contrast for each response channel of the image sensor of the RGB filter system. In endoscopic applications, the observation, resolution and identification of specific tissues are particularly critical for inspection and diagnosis, especially the identification of different types of blood vessels in the group; hemoglobin in blood vessels has a specific absorption spectrum, and the emission spectrum of conventional white light LEDs does not match the absorption spectrum, resulting in low specificity of blood vessels under conventional white light LED illumination. Therefore, the conventional white light LEDs currently used will reduce the image's ability to distinguish different tissues in endoscopic applications, which is not conducive to doctors' diagnosis. Summary of the invention

[0004] An endoscope and a lighting device thereof provided by the present invention effectively solve the problem that the existing lighting device cannot improve the recognition accuracy of the image during the endoscope imaging lighting process.

[0005] According to a first aspect, an embodiment provides a lighting device for an endoscope, comprising an LED light source and a light source controller;

[0006] The light source controller is used to control the LED light source to emit a combination of white light consisting of purple light waves, blue light waves, green light waves and red light waves;

[0007] The first peak and the second peak of the combined white light spectrum; the peak wavelength of the first peak is in the wavelength range of 400nm-430nm; the peak wavelength of the second peak is in the wavelength range of 520nm-560nm;

[0008] The energy proportion of the peak value of the first wave is the highest in the combined white light spectrum.

[0009] In an achievable implementation, the spectrum of the combined white light further includes a third wave peak, and the peak wavelength of the third wave peak is within a waveband range of 615 nm-660 nm.

[0010] In an achievable implementation, the combined white light spectrum also includes a fourth peak, the peak wavelength of the fourth peak is in the 440nm-470nm band; the ratio of the energy proportion of the first peak to the energy proportion of the fourth peak is greater than 1:0.8.

[0011] In an achievable implementation, the spectrum of the combined white light further includes a first wave valley and a second wave valley;

[0012] The wavelength of the lowest valley value of the first valley is in the wavelength range of 470nm-515nm, and the wavelength of the lowest valley value of the second valley is in the wavelength range of 570nm-610nm;

[0013] The difference between the energy ratio of the lowest valley value of any of the first valley and the second valley and the energy ratio of the highest peak-to-peak value of the adjacent peak is greater than 0.1.

[0014] In an achievable implementation, a ratio of the energy proportion of the first peak-to-peak value to the energy proportion of the second peak-to-peak value is greater than 1:0.85.

[0015] In an achievable implementation, the LED light source includes a purple semiconductor light-emitting chip; a phosphor layer is provided on the surface of the purple semiconductor light-emitting chip, and the phosphor layer includes blue phosphor, green phosphor and red phosphor;

[0016] The purple semiconductor light emitting chip is used to emit purple light waves, the blue phosphor is used to emit blue light waves, the green phosphor is used to emit green light waves, and the red phosphor is used to emit red light waves;

[0017] The purple light emitted by the purple semiconductor light emitting chip has an emission peak wavelength in the wavelength range of 400nm-430nm, and a half-wave width of less than 30nm;

[0018] The emission peak wavelength of the green light wave emitted by the green phosphor is in the range of 520nm-560nm, and the half-wave width is 50nm-120nm.

[0019] In an achievable implementation, the red light wave emitted by the red phosphor has an emission peak wavelength in the 615nm-660nm band, and a half-wave width of 70nm-110nm.

[0020] In an achievable implementation, the blue light wave emitted by the blue phosphor has an emission peak wavelength in the 440nm-470nm band, and a half-wave width of 40nm-90nm.

[0021] According to the second aspect, an embodiment provides an endoscope, comprising the lighting device as described above, wherein the LED light source is disposed at a distal end of a body of the endoscope.

[0022] In a feasible embodiment, the distal end of the endoscope body is further provided with an RGB image sensor, and the RGB image sensor is used to receive the illumination light reflected after the LED light source irradiates the target tissue, and to perform imaging based on the reflected illumination light.

[0023] According to the above embodiment, a lighting device for endoscope is used, and the light source controller controls the LED light source to emit a combination of white light composed of purple light waves, blue light waves, green light waves and red light waves, wherein the spectrum of the combined white light includes a first wave peak and a second wave peak, and the peak wavelength of the first wave peak is located in the band range of 400nm-430nm, and this wavelength range overlaps with the wavelength range of the strongest absorption peak of the light wave of the hemoglobin in the blood vessels of human tissue; the peak wavelength of the second wave peak in the spectrum of the combined white light is located in the band range of 520nm-560nm, and this wavelength range overlaps with the wavelength range of the second strongest absorption peak of the light wave of the hemoglobin in the blood vessels of human tissue. Therefore, by using the lighting device of the present application to perform endoscopic imaging, the LED light source of the present application can make the hemoglobin achieve a higher response in each response channel of the RGB image sensor, thereby effectively improving the distinction between tissue containing hemoglobin and tissue not containing hemoglobin in the image. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of the structure of an endoscope and a lighting device thereof provided in this embodiment;

[0025] Figure 2 is a graph showing the relationship between the first LED spectrum emitted by the lighting device of this embodiment, the hemoglobin absorption coefficient, and the image sensor response curve;

[0026] Figure 3 is a graph showing the relationship between the second LED spectrum emitted by the lighting device of this embodiment, the hemoglobin absorption coefficient, and the image sensor response curve;

[0027] Figure 4This is a diagram showing the relationship between the third LED spectrum emitted by the lighting device of this embodiment, the hemoglobin absorption coefficient, and the image sensor response curve.

[0028] Reference numerals: 100, LED light source; 200, light source controller; 300, RGB image sensor; 400, front end portion. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below by specific embodiments in conjunction with the accompanying drawings. Wherein similar elements in different embodiments adopt associated similar element numbers. In the following embodiments, many detailed descriptions are for making the present application better understood. However, those skilled in the art can easily recognize that some features can be omitted in different situations, or can be replaced by other elements, materials, methods. In some cases, some operations related to the present application are not shown or described in the specification, this is to avoid the core part of the present application being overwhelmed by too much description, and for those skilled in the art, it is not necessary to describe these related operations in detail, and they can fully understand the related operations according to the description in the specification and the general technical knowledge in the art.

[0030] In addition, the features, operations or characteristics described in the specification can be combined in any appropriate manner to form various implementations. At the same time, the steps or actions in the method description can also be interchanged or adjusted in a manner that is obvious to those skilled in the art. Therefore, the various sequences in the specification and the drawings are only for the purpose of clearly describing a certain embodiment and are not meant to be a required sequence, unless otherwise specified that a certain sequence must be followed.

[0031] The serial numbers of the components in this document, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" and "coupling" mentioned in this application, unless otherwise specified, include direct and indirect connections (couplings).

[0032] Human tissues, especially vascular tissues and blood, contain a large amount of hemoglobin, which has a special absorption spectrum for light of different wavelengths. Oxygenated hemoglobin has strong absorption peaks near 415nm, 540nm and 575nm, and its absorption coefficient is very small in the band greater than 600nm. In other words, when light in the 380nm-450nm band is irradiated on hemoglobin, it will be strongly absorbed, and when light in the 520nm-600nm band is irradiated on hemoglobin, it will be partially absorbed, and when light in the band greater than 600nm is irradiated on hemoglobin, it will be strongly reflected due to low absorption. At the same time, human tissue is a scattering material for light. According to the laws of physics, light with shorter wavelengths is more strongly scattered in human tissues, and short waves are transmitted over short distances in human tissues; while light with longer wavelengths is less scattered in human tissues, and long waves are transmitted over long distances in human tissues. Therefore, in the field of tissue imaging, the spectral absorption characteristics of hemoglobin and the scattering characteristics of human tissues can be used to perform special imaging of vascular tissues at different depths in the human body. Therefore, combining the response characteristics of image sensors and the bio-optical characteristics of human tissue, the present application proposes an illumination device that can be used for endoscopic imaging to improve the representation of blood vessels in endoscopic images.

[0033] like Figure 1 As shown, the present embodiment provides an illumination device for an endoscope, comprising an LED light source 100 and a light source controller 200; the light source controller 200 is used to control the LED light source 100 to emit a combined white light composed of purple light waves, blue light waves, green light waves and red light waves; the spectrum of the combined white light comprises a first wave peak and a second wave peak; the peak wavelength of the first wave peak is in the wave band range of 400nm-430nm; the peak wavelength of the second wave peak is in the wave band range of 520nm-560nm; wherein, the energy proportion of the peak value of the first wave peak is the highest in the combined white light spectrum.

[0034] The lighting device of this embodiment controls the switch of the LED light source 100 through the light source controller 200 to achieve lighting. Specifically, after the LED light source 100 is turned on, it can emit a combination of white light composed of purple light waves, blue light waves, green light waves and red light waves. The combined white light spectrum contains at least a first peak and a second peak, wherein the first peak is the peak wavelength corresponding to the purple light wave and is located in the band range of 400nm-430nm. Among them, the peak energy of the first peak has the highest proportion, that is, the highest peak wavelength of the entire combined white light spectrum is located in the purple light band (i.e., the purple light band) within the range of 400nm-430nm, and this wavelength range overlaps with the wavelength range of the strongest absorption peak of the light wave of the hemoglobin in the blood vessels of human tissue. When performing endoscopic imaging, the LED light source 100 is used for imaging illumination. The purple light with the highest content in the combined white light emitted by the light source will be strongly absorbed by the blood vessels of human tissue. Since the penetration depth of the purple light in the tissue is small, the blood vessels in the surface tissue of the human body will strongly absorb the purple light, and the surface non-vascular tissue will reflect the purple light. During endoscopic imaging, the image output by the blue response channel in the RGB image sensor 300 has a relatively low grayscale of the blood vessel image in the output image because the purple light is absorbed by the blood vessels. On the contrary, the grayscale of the surface non-vascular tissue in the image is relatively high.

[0035] In addition, the peak wavelength corresponding to the green light wave of the second peak in the combined white light spectrum is located in the wavelength range of 520nm-560nm, and this wavelength range overlaps with the wavelength range of the second strongest absorption peak of the light wave of the hemoglobin in the blood vessels of human tissue. During endoscopic imaging, the green light with a higher content in the white light emitted by the light source will be absorbed by the blood vessels of human tissue. Since the green light penetrates deeply in the tissue, the blood vessels in the middle layer of the human body will strongly absorb the green light, and the non-vascular tissue will reflect the green light. During endoscopic imaging, the grayscale of the blood vessel image in the middle layer of the human body in the output image of the green response channel of the RGB image sensor 300 is relatively low because the green light is absorbed by the blood vessels. On the contrary, the grayscale of the non-vascular tissue in the image is relatively high, that is, the contrast between the middle layer of blood vessels and non-vascular tissue is high, and the middle layer of blood vessels is easier to observe in the image.

[0036] Furthermore, in some embodiments, the spectrum of the combined white light also includes a third wave peak, wherein the peak wavelength of the third wave peak is located in the red light band (i.e., the red light band) of 615nm-660nm, and this wavelength range is located in the wavelength range where the light wave absorption of the hemoglobin in the blood vessels of human tissue is the smallest. During endoscopic imaging, the red light with a high content in the combined white light emitted by the light source will be strongly reflected by the blood vessels of human tissue. Since the red light penetrates deeply into the tissue, the blood vessels in the middle and deep tissues of the human body will be strongly reflected, and the non-vascular tissue will transmit or scatter the red light. During endoscopic imaging, the image output by the red response channel of the RGB image sensor 300 is relatively high in grayscale of the blood vessel image in the output image because the red light is reflected by the blood vessels. On the contrary, the grayscale of the non-vascular tissue in the image is relatively low, that is, the contrast between the blood vessels and the non-vascular tissue is high, and the blood vessels are easier to observe in the image.

[0037] Furthermore, in some embodiments, the spectrum of the combined white light also includes a fourth wave peak, wherein the peak wavelength of the fourth wave peak is in the blue light band (i.e., the blue light band) of 440nm-470nm nm, and the ratio of the energy proportion of the first wave peak to the energy proportion of the fourth wave peak is greater than 1:0.8. Adding appropriate blue light waves to the combined white light can make the LED light source 100 in the present application more consistent with the spectral response characteristics of the human eye and increase the color rendering of blue; blue light waves penetrate deeper into human tissues than purple light waves, and adding blue light waves can increase the recognition of tissues below the superficial layer. On the other hand, in the LED light source 100 of the present embodiment, the higher the proportion of the purple light wave (400nm-430nm), the lower the proportion of the blue light wave (440nm-470nm) also responded to by the blue response channel in the RGB image sensor 300, the greater the grayscale difference between the surface blood vessels and non-vascular tissues in the grayscale image output by the blue channel, that is, the higher the contrast between the surface blood vessels and the non-vascular tissues, the easier it is to observe the surface blood vessels in the image. Therefore, the proportion of blue light wave energy should not be too high. Furthermore, in the present embodiment, the ratio of the energy proportion of the peak value of the purple light wave to the energy proportion of the peak value of the blue light wave is greater than 1:0.8.

[0038] As an implementation of this embodiment, the LED light source 100 includes a purple semiconductor light emitting chip; a phosphor layer is provided on the surface of the purple semiconductor light emitting chip, and the phosphor layer can be formed by mixing blue phosphor, green phosphor and red phosphor, etc. Specifically, the purple semiconductor light emitting chip is used to emit purple light waves, the blue phosphor is used to emit blue light waves, the green phosphor is used to emit green light waves, and the red phosphor is used to emit red light waves.

[0039] Specifically, the LED light source 100 that emits a combination of white light composed of purple light waves, blue light waves, green light waves, and red light waves is composed of a purple semiconductor light-emitting chip and a mixed phosphor layer formed by blue phosphor, green phosphor, red phosphor, etc. Specifically, the mixed phosphor layer is arranged on the surface of the purple semiconductor light-emitting chip. The light-emitting principle is that the narrow-band purple light waves emitted by the purple semiconductor light-emitting chip and the blue light waves, green light waves, and red light waves emitted by the mixed phosphor layer after being excited by the purple light waves together form a combination of white light.

[0040] Among them, the peak wavelength of the narrow-band purple light wave emitted by the purple semiconductor light-emitting chip is in the wavelength range of 400nm-430nm, and its half-wave width is less than 30nm. The blue phosphor can be a silicate blue phosphor, a chlorophosphate blue phosphor, or an oxide blue phosphor, or other types of blue phosphors, with a peak wavelength of 440nm-470nm and a half-wave width of about 40nm-90nm. The green phosphor can be an aluminate green phosphor, a phosphate green phosphor, a halogenated green phosphor, a silicate green phosphor, or a nitride green phosphor, or other types of green phosphors, with a peak wavelength of 520nm-560nm and a half-wave width of about 50nm-120nm. The red phosphor can be a nitride red phosphor, a sulfide red phosphor, or a fluoride red phosphor, or other types of red phosphors, with a peak wavelength of 615nm-660nm and a half-wave width of about 70nm to 110nm.

[0041] Furthermore, the spectrum of the combined white light formed by the purple light wave, the blue light wave, the green light wave and the red light wave also includes a first wave valley and a second wave valley; wherein the wavelength of the lowest wave valley value of the first wave valley is in the wave band range of 470nm-515nm, and the wavelength of the lowest wave valley value of the second wave valley is in the wave band range of 570nm-610nm. wherein the difference between the energy proportion of the lowest wave valley value of any wave valley of the first wave valley and the second wave valley and the energy proportion of the highest peak value of the adjacent wave peak is greater than 0.1.

[0042] In this embodiment, there are at least two obvious valley regions in the spectrum of the combined white light formed by the purple light wave, the blue light wave, the green light wave and the red light wave. Figure 2-Figure 4It can be seen that since the wavelength of the lowest valley value of the first valley is in the band range of 470nm-515nm, this range is exactly at the intersection of the spectrum's response to the blue response channel and the green response channel of the RGB image sensor 300. If the output intensity of the combined white light is not reduced at this time, the white light spectrum will respond to the blue response channel and the green response channel at the same time, which will cause crosstalk in the output images of the blue response channel and the green response channel of the RGB image sensor 300, affecting the imaging effect. In this embodiment, the output intensity of the combined white light is reduced at the intersection, specifically by setting the first trough, so that the output intensity of the combined white light is reduced within the wavelength range of 470nm-515nm of the white light spectrum. At this time, the blue response channel of the RGB image sensor 300 has a low response to the light energy within this wavelength range, and because the peak wavelength of green light in the spectrum is within the range of 520nm-560nm of the green light band, the green light energy of the combined white light has little effect on the blue response channel, thereby reducing the crosstalk between the output images of the blue response channel and the green response channel of the RGB image sensor 300, so that the blue response channel and the green response channel in the image can be more distinguished.

[0043] The wavelength of the lowest valley value of the second valley is located in the band range of 570nm-610nm, which is just at the intersection of the spectrum response to the green response channel and the red response channel of the RGB image sensor 300. Similarly, if the output intensity of the combined white light is not reduced at this time, the white light spectrum will respond to the green response channel and the red response channel at the same time, which will cause crosstalk between the green response channel and the red response channel of the image sensor, affecting the imaging effect. In this embodiment, the output intensity of the combined white light is reduced at the intersection, specifically by setting the second valley to reduce the output intensity of the combined white light in the band range of 570nm-610nm. At this time, the green response channel of the image sensor has a low response to the light energy in this band range, and since the peak wavelength of red light in the spectrum is located in the red light band range of 615nm-660nm, the red light energy of the combined white light has little effect on the green response channel, thereby reducing the crosstalk between the output images of the red response channel and the green response channel of the image sensor, so that the red response channel and the green response channel in the image are more distinguishable.

[0044] Moreover, the difference between the energy proportion of the highest peak of the peak adjacent to the first trough and the energy proportion of the lowest trough of the first trough is greater than 0.1; the difference between the energy proportion of the highest peak of the peak adjacent to the second trough and the energy proportion of the lowest trough of the second trough is greater than 0.1.

[0045] Specifically, for example, in the combined white light spectrum, the first wave valley is located between the fourth wave peak and the second wave peak, then the fourth wave peak and the second wave peak are both peaks adjacent to the first wave valley. Then the energy proportion of the highest peak value of the fourth wave peak is subtracted from the energy proportion of the lowest valley value of the first wave valley, and the difference obtained is greater than 0.1. For example, Figure 4 , the energy proportion of the highest peak value of the fourth wave peak is 0.61, the energy proportion of the lowest valley value of the first wave valley is 0.48, the difference between the energy proportion of the highest peak value of the fourth wave peak and the energy proportion of the lowest valley value of the first wave valley is 0.13, so 0.13 is greater than 0.1. Similarly, the difference between the energy proportion of the highest peak value of the second wave peak and the energy proportion of the lowest valley value of the first wave valley is greater than 0.1.

[0046] For the second trough, the principle is the same as that for the first trough. For example, in the combined white light spectrum, the second trough is located between the second peak and the third peak. Then, the second peak and the third peak are both peaks adjacent to the second trough. Then, the difference between the energy proportion of the highest peak of the second peak and the energy proportion of the lowest valley of the second trough is greater than 0.1. Similarly, the difference between the energy proportion of the highest peak of the third peak and the energy proportion of the lowest valley of the second trough is greater than 0.1.

[0047] Such a design can better highlight the difference between the peaks and troughs, thereby ensuring that the crosstalk between the response channels of the image sensor is smaller. In addition, since the above-mentioned characteristic troughs (i.e., the first trough and the second trough) are located at the overlapping position of the spectral response curves of the blue response channel, the green response channel, and the red response channel of the image sensor, the energy proportion of the characteristic trough is low, the illumination intensity at the characteristic trough position is low, and the grayscale image with the same wavelength in the output image of the blue response channel, the green response channel, and the red response channel of the image sensor is low, so that the contrast of the red, green, and blue color corresponding images after the color image is synthesized is high.

[0048] In some embodiments, further, the ratio of the energy proportion of the peak value of the first wave peak of the combined white light spectrum to the energy proportion of the peak value of the second wave peak is greater than 1:0.85. Generally, the green response channel in the RGB image sensor 300 has the highest responsiveness, and the responsiveness of the blue response channel is relatively low. The first wave peak is the purple light band responded by the blue response channel, and the second wave peak is the green light band responded by the green response channel. A higher energy proportion of the first wave peak can make the response of the blue response channel higher, which is beneficial to highlight superficial blood vessels in endoscopic applications.

[0049] In some embodiments, specifically, the light-emitting chip of the LED light source 100 uses a purple semiconductor light-emitting chip with a peak wavelength of 415nm and a half-wave width of 15nm; the blue powder uses a blue phosphor with a peak wavelength of 450nm and a half-wave width of 50nm; the green powder uses a green phosphor with a peak wavelength of 540nm and a half-wave width of 56nm; the red powder uses a red phosphor with a peak wavelength of 630nm and a half-wave width of 85nm, and the use ratio and concentration of the three phosphors are adjusted so that the output intensity ratio of the purple light wave, the blue light wave, the green light wave and the red light wave is output according to the ratio of 1:0.65:0.7:0.6, and the following can be obtained: Figure 2 The white light LED spectrum curve is shown.

[0050] Figure 2 In the white light LED spectrum curve shown, the color temperature of white light is 5060K, the color coordinates are CIE1931-x: 0.3421, CIE1931-y: 0.3375, the color rendering index CRI is 89, and the color rendering index R9 is 93. Among them, the peak wavelength of the highest peak (first wave peak) of white light is located at 415nm, the peak wavelength of the peak of the green band (second wave peak) is located at 542nm, the relative intensity is 0.79, the peak wavelength of the peak of the red band (third wave peak) is located at 645nm, the relative intensity is 0.68, the peak wavelength of the peak of the blue band (fourth wave peak) is located at 450nm, the relative intensity is 0.67, the lowest valley value of the first valley is located at 502nm, the relative intensity is 0.3, and the lowest valley value of the second valley is located at 580nm, the relative intensity is 0.53.

[0051] It should be noted that since the phosphor emission wavelength range is wider, the relative intensity corresponding to the peak value of each color band is the energy of other color bands added. Therefore, the relative intensity corresponding to the peak value of each color band is greater than the output intensity of a single phosphor emission band.

[0052] In some embodiments, specifically, the light-emitting chip of the LED light source 100 uses a purple semiconductor light-emitting chip with a peak wavelength of 415nm and a half-wave width of 15nm; the blue powder uses a blue phosphor with a peak wavelength of 460nm and a half-wave width of 82nm; the green powder uses a green phosphor with a peak wavelength of 540nm and a half-wave width of 56nm; the red powder uses a red phosphor with a peak wavelength of 630nm and a half-wave width of 85nm, and the use ratio and concentration of the three phosphors are adjusted so that the output intensity ratio of the purple light wave, the blue light wave, the green light wave and the red light wave is output according to the ratio of 1:0.6:0.6:0.6, and the following can be obtained: Figure 3 The white light LED spectrum curve is shown.

[0053] Figure 3In the white light LED spectrum curve shown, the color temperature of white light is 5543K, the color coordinates are CIE1931-x: 0.3314, CIE1931-y: 0.3408, the color rendering index CRI is 94, and the color rendering index R9 is 81. Among them, the peak wavelength of the highest peak (first wave peak) of white light is located at 415nm, the peak wavelength of the peak of the green band (second wave peak) is located at 542nm, the relative intensity is 0.75, the peak wavelength of the peak of the red band (third wave peak) is located at 625nm, the relative intensity is 0.66, the peak wavelength of the peak of the blue band (fourth wave peak) is located at 470nm, the relative intensity is 0.59, the lowest valley value of the first valley is located at 508nm, the relative intensity is 0.45, and the lowest valley value of the second valley is located at 580nm, the relative intensity is 0.48.

[0054] In some embodiments, specifically, the light-emitting chip of the LED light source 100 uses a purple semiconductor light-emitting chip with a peak wavelength of 415nm and a half-wave width of 15nm; the blue powder uses a blue phosphor with a peak wavelength of 450nm and a half-wave width of 52nm; the green powder uses a green phosphor with a peak wavelength of 525nm and a half-wave width of 107nm; the red powder uses a red phosphor with a peak wavelength of 650nm and a half-wave width of 86nm, and the use ratio and concentration of the three phosphors are adjusted so that the output intensity ratio of the purple light wave, the blue light wave, the green light wave and the red light wave is output according to the ratio of 1:0.56:0.65:0.6, and the following can be obtained: Figure 4 The white light LED spectrum curve is shown.

[0055] Figure 4 In the white light LED spectrum curve shown, the color temperature of white light is 5507K, the color coordinates are CIE1931-x: 0.3326, CIE1931-y: 0.3625, the color rendering index CRI is 92, and the color rendering index R9 is 81. Among them, the peak wavelength of the highest peak (first wave peak) of white light is located at 415nm, the peak wavelength of the peak of the green band (second wave peak) is located at 525nm, the relative intensity is 0.75, the peak wavelength of the peak of the red band (third wave peak) is located at 650nm, the relative intensity is 0.71, the peak wavelength of the peak of the blue band (fourth wave peak) is located at 450nm, the relative intensity is 0.61, the lowest valley value of the first valley is located at 472nm, the relative intensity is 0.47, and the lowest valley value of the second valley is located at 592nm, the relative intensity is 0.51.

[0056] Compared with the conventional white light LED, the lighting device of the present application has the following characteristics: first, the highest peak wavelength in the spectrum of the white light LED of the present application is located in the violet light band, and the wavelength position overlaps with the highest absorption peak of hemoglobin, which can increase the recognition of superficial blood vessels when used for endoscopic imaging lighting. Secondly, there are characteristic peaks and characteristic troughs in the green and red light bands. The characteristic peak of the green light band overlaps with the second highest absorption peak of hemoglobin, which can increase the recognition of middle-layer blood vessels when used for endoscopic imaging lighting; the characteristic peak of the red light band is located in the area with low absorption rate of hemoglobin, which can increase the recognition of deep blood vessels when used for endoscopic imaging lighting. Thirdly, the two characteristic troughs in the spectrum of the white light LED of the present application are respectively located at the intersection of the blue response channel and the green response channel of the RGB image sensor 300 and the intersection of the green response channel and the red response channel. The low energy of the trough reduces the crosstalk between the three response channels of the image sensor and increases the contrast of different response channels. At the same time, the characteristic peaks of the purple light band, the green light band and the red light band in the present application are respectively located in the blue response channel, the green response channel and the red response channel of the image sensor, so that when imaging using the LED light source 100 and the RGB image sensor 300 of the present application, the superficial blood vessels, the middle blood vessels and the deep blood vessels have higher recognition and contrast.

[0057] An endoscope provided in this embodiment includes the lighting device as described above, specifically, an LED light source 100 is arranged at the front end 400 of the endoscope body. Because the structure of the LED light source 100 of this solution is designed to only use a semiconductor light-emitting chip combined with a phosphor layer on the surface to achieve combined white light, the white light LED has uniform light mixing, simple structure, compact size, reliable performance, and low cost. When the LED light source 100 is placed at the front end 400 of the endoscope body, the light source can be used directly for endoscopic imaging illumination, which is beneficial to improving energy utilization, and can ensure lighting consistency, and further improve the endoscopic imaging quality. In this way, the imaging performance of the lighting device of the present application is effectively improved when used for endoscopic imaging illumination, and the manufacturing cost is low, it is easy to use, and is conducive to popularization and application.

[0058] In addition, the front end 40 of the endoscope body of this embodiment is also provided with an RGB image sensor 300. After the LED light source 100 irradiates the target tissue, it will reflect the illumination light. At this time, the reflected illumination light is received by the RGB image sensor 300, and then the RGB image sensor 300 will form an image based on the received illumination light.

[0059] In addition, since the LED lighting device has been described in detail in the above embodiments, this embodiment will not be described in detail here.

[0060] The above specific examples are used to illustrate the present invention, which is only used to help understand the present invention and is not intended to limit the present invention. For those skilled in the art, according to the concept of the present invention, some simple deductions, modifications or substitutions can be made.

Claims

1. A lighting device for an endoscope, characterized in that: It includes an LED light source and a light source controller; The light source controller is used to control the LED light source to emit a combination of white light consisting of purple light waves, blue light waves, green light waves and red light waves; The spectrum of the combined white light includes a first wave peak and a second wave peak; the peak wavelength of the first wave peak is in the wave band range of 400nm-430nm; the peak wavelength of the second wave peak is in the wave band range of 520nm-560nm; The energy proportion of the peak value of the first wave is the highest in the combined white light spectrum.

2. The lighting device according to claim 1, characterized in that: The spectrum of the combined white light also includes a third wave peak, and the peak wavelength of the third wave peak is in the wave band range of 615nm-660nm.

3. The lighting device according to claim 1, characterized in that: The combined white light spectrum also includes a fourth wave peak, and the peak wavelength of the fourth wave peak is in the waveband range of 440nm-470nm; The ratio of the energy proportion of the first peak-to-peak value to the energy proportion of the fourth peak-to-peak value is greater than 1:0.

8.

4. The lighting device according to claim 1, characterized in that: The spectrum of the combined white light also includes a first wave valley and a second wave valley; The wavelength of the lowest valley value of the first valley is in the wavelength range of 470nm-515nm, and the wavelength of the lowest valley value of the second valley is in the wavelength range of 570nm-610nm; The difference between the energy ratio of the lowest valley value of any of the first valley and the second valley and the energy ratio of the highest peak-to-peak value of the adjacent peak is greater than 0.

1.

5. The lighting device according to claim 1, characterized in that: The ratio of the energy proportion of the first peak-to-peak value to the energy proportion of the second peak-to-peak value is greater than 1:0.

85.

6. The lighting device according to claim 1, characterized in that: The LED light source comprises a purple semiconductor light emitting chip; a phosphor layer is arranged on the surface of the purple semiconductor light emitting chip, and the phosphor layer comprises blue phosphor, green phosphor and red phosphor; The purple semiconductor light emitting chip is used to emit purple light waves, the blue phosphor is used to emit blue light waves, the green phosphor is used to emit green light waves, and the red phosphor is used to emit red light waves; The purple light emitted by the purple semiconductor light emitting chip has an emission peak wavelength in the wavelength range of 400nm-430nm, and a half-wave width of less than 30nm; The emission peak wavelength of the green light wave emitted by the green phosphor is in the range of 520nm-560nm, and the half-wave width is 50nm-120nm.

7. The lighting device according to claim 6, characterized in that: The red light wave emitted by the red phosphor has an emission peak wavelength in the 615nm-660nm band, and a half-wave width of 70nm-110nm.

8. The lighting device according to claim 6, characterized in that: The blue light wave emitted by the blue phosphor has an emission peak wavelength in the 440nm-470nm band, and a half-wave width of 40nm-90nm.

9. An endoscope, characterized in that: It comprises the lighting device as described in any one of claims 1 to 8, wherein the LED light source is arranged at the front end of the endoscope body.

10. The endoscope according to claim 9, characterized in that The front end of the endoscope is also provided with an RGB image sensor, which is used to receive the illumination light reflected after the LED light source irradiates the target tissue and to perform imaging based on the reflected illumination light.

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