A light emitting device and a lamp

Abstract

The present invention discloses a lighting device and a lamp, including a light source with a center point B and a spherical reflector with a radius R and a center O. The concave surface of the spherical reflector is a reflecting surface. The light source emits light toward the reflecting surface. After the light is reflected by the reflecting surface, a converging light beam is formed. The converging light beam converges at an exit focus A. The length between the center point B of the light source and the exit focus A is L. The line connecting the exit focus A and the center B of the light source is a line segment C. The line segment C is located between the center O and the reflecting surface. The distance from the center O to the line segment C is y. A spherical surface that is easy to process and obtain is used to replace an ellipsoidal surface. In order to use the spherical surface to also play the role of an ellipsoidal surface, the technical solution discloses the positional relationship between the light source light point, the center of the spherical surface and the exit focus of the converging light beam, so as to achieve the effect of replacing the ellipsoidal surface with a spherical surface; each beam of light emitted by the light-emitting surface is reflected by the spherical surface and returns to the light-emitting surface as much as possible.

Description

Technical Field

[0001] The present invention relates to the field of lighting technology, and in particular to a light emitting device and a lamp. Background Art

[0002] In existing light emitting devices, in order to control the light emitting angle and light emitting brightness of the emitted light, the light emitting angle and light emitting brightness of the emitted light are generally controlled by controlling the light source to emit light at a large angle or a small angle.

[0003] For example, Shenzhen Guangfeng Optoelectronics Technology Co., Ltd. applied for a projection system named "light-emitting device and its application" on December 4, 2011, application number: CN201110396392.4. Figure 1 The application discloses the following technical features: preferably, the second light reflecting element 140 may be in the shape of a hemisphere or a part of a hemisphere, the position where the coherent light enters the diffusing element 120 is located at a first point close to the center of the hemisphere, the light entrance of the light collecting device 160 is located at a second point close to the center of the hemisphere, and the first point and the second point are symmetrical about the center of the hemisphere. The coherent light emitted by the coherent light source 110 enters the diffusing element 120 through the light hole 130, and the incoherent light emitted by the second surface 122 of the diffusing element 120 is reflected by the first light reflecting element 150 and then emitted to the second light reflecting element 140 together with the incoherent light emitted by the first surface 121 of the diffusing element. The reflective surface of the second light reflecting element 140 reflects most of the incoherent light to the light entrance of the light collecting device located at the second point close to the center of the hemisphere, and most of the incoherent light is collected by the light collecting device 160 and emitted as the output light of the light emitting device 200.

[0004] This technical solution details the use of a hemisphere or a part of a hemisphere, wherein the position where the coherent light is incident is located at a first point close to the center of the hemisphere, and the light port of the collection device is located at a second point close to the center of the hemisphere, and the first point and the second point are symmetrical about the center of the hemisphere. This prior art provides a technical solution for light emission using a hemisphere or a part of a hemisphere. Summary of the invention

[0005] The object of the present invention is to overcome the shortcomings of the above-mentioned conventional technology. The present invention provides a light emitting device for controlling light recycling and light emission.

[0006] In order to solve the above problems, the technical solution adopted by the present invention is: a light-emitting device, characterized in that: it includes a light source with a center point B and a spherical reflector with a radius R and a center O, the concave surface of the spherical reflector is a reflecting surface, the light source emits light toward the reflecting surface, and the light is reflected by the reflecting surface to form a converging light beam, which converges at an exit focus A, the length between the center point B of the light source and the exit focus A is L, the line connecting the exit focus A and the center B of the light source is a line segment C, the foot of the perpendicular from the center O to the line segment C is located in the middle of the line segment C, the line segment C is located between the center O and the reflecting surface, the distance from the center O to the line segment C is y, and the

[0007] A light-emitting device comprises a light source having a light-emitting surface and a spherical reflector with a radius of R, wherein: the center of the spherical reflector is O, the concave surface of the spherical reflector is a reflective surface, the light-emitting surface emits light toward the reflective surface, the diameter of the circumscribed circle of the light-emitting surface is L, the foot of the perpendicular from the center of the sphere O to the light-emitting surface is located at the center of the light-emitting surface, the light-emitting surface is located between the center of the sphere O and the reflective surface, the distance from the geometric center C of the light-emitting surface to the center of the sphere O is y, and the

[0008] As an improvement of the above technical solution:

[0009] As an improvement of the above technical solution: the light source is an LED light-emitting chip, and the light-emitting surface of the LED light-emitting chip is covered with fluorescent material.

[0010] As an improvement of the above technical solution: the light source is a fluorescent light-emitting device, and also includes a laser light source for exciting the fluorescent light-emitting device. The laser light source emits laser light, which excites the fluorescent light-emitting device, and the fluorescent light-emitting device is excited to emit fluorescence.

[0011] As an improvement of the above technical solution: the fluorescent light-emitting device is a reflective fluorescent sheet, and the laser light source is arranged on the side of the reflective surface away from the reflective fluorescent sheet; a light hole is arranged on the reflective surface, and the laser excites the reflective fluorescent sheet after passing through the light hole.

[0012] As an improvement of the above technical solution: a second reflective surface is arranged corresponding to the area where the light-through hole is opened, and a part of the fluorescence emitted by the reflective fluorescent sheet reaches the second reflective surface and is reflected back to the reflective fluorescent sheet by the second reflective surface, and the second reflective surface is coated with a coating layer that transmits laser and reflects fluorescence.

[0013] As an improvement of the above technical solution: the light source further includes an LED light-emitting chip closely attached to the fluorescent light-emitting device.

[0014] As an improvement of the above technical solution: it also includes a light emitting portion, the reflective surface covers a part of the light emitted by the light emitting surface, and the other part of the light emitted by the light emitting surface is emitted through the light emitting portion.

[0015] Due to the adoption of the above technical solution, compared with the prior art, when the light emitting device of the present invention is used, a spherical surface that is easy to process and obtain is used to replace the ellipsoidal surface. In order to use the spherical surface to also play the role of the ellipsoidal surface, the formula for the positional relationship between the light source light point, the spherical center and the outgoing focus of the convergent light beam is disclosed in the technical solution, which plays the effect of replacing the ellipsoidal surface with a spherical surface;

[0016] By controlling the distance between the light source with the light-emitting surface and the spherical surface in practical applications, each beam of light emitted by the light-emitting surface is reflected by the spherical surface and returns to the light-emitting surface as much as possible.

[0017] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The application of ellipsoid in the prior application

[0019] Figure 2 It is the application of sphere in the prior application.

[0020] Figure 3 is a cross-sectional view of a light emitting device.

[0021] Figure 4 is a cross-sectional view of a light emitting device.

[0022] Figure 5 is a cross-sectional view of a light emitting device.

[0023] Figure 6 is a cross-sectional view of a light emitting device.

[0024] Figure 7 is a cross-sectional view of a light emitting device.

[0025] Figure 8 is a cross-sectional view of a light emitting device.

[0026] Fig. 9 is a cross-sectional view of a light emitting device.

[0027] Fig.10 is a cross-sectional view of a light emitting device. DETAILED DESCRIPTION

[0028] Embodiment 1:

[0029] In the prior art, the patent application number: CN201110396392.4 points out that when light is emitted, hemispherical or spherical reflection is used, and the position where the light scattering element 120 is incident by the coherent light is located at a first point close to the center of the hemispherical ball, and the light entrance of the light collecting device 160 is located at a second point close to the center of the hemispherical ball, and the first point and the second point are symmetrical about the center of the hemispherical ball. However, the applicant has found through experiments that the first point and the second point given by the above technical solution are not the most ideal situation.

[0030] like Figure 3 As shown, a light-emitting device includes a light source 101 with a center point B and a spherical reflector 102 with a radius R and a center O. The concave surface of the spherical reflector 102 is a reflective surface 103. The light source 101 emits light facing the reflective surface 103. The light is divided into a first angle light 121 and a second angle light according to different light-emitting angles. In this embodiment, the first angle light 121 is a small angle light, and the second angle light is a large angle light. After the first angle light 121 is reflected by the reflective surface 103, a convergent light beam 122 is formed. The convergent light beam 122 converges at an exit focus A. The length between the center point B of the light source and the exit focus A is L. The line connecting the exit focus A and the center point B of the light source is a line segment C. The foot of the perpendicular from the center O to the line segment C is located in the middle of the line segment C. The line segment C is located between the center O and the reflective surface. The distance from the center O to the line segment C is y.

[0031] The light source 101 is directed toward the reflective surface 103 of the spherical reflector 102 to emit light, and the area of ​​the reflective surface is controlled to control the luminous angle of the convergent light beam 122. According to geometric principles combined with optical knowledge, any beam of light emitted from one focus of an ellipsoid will return to another focus of the ellipsoid after being reflected by the ellipsoid surface.

[0032] Ideally, the center point B of the light source 101 coincides with one focus of the ellipsoid, and the emission focus A coincides with another focus of the ellipsoid. Any beam of light emitted from the center point B of the light source 101 will be emitted from the emission focus A after being reflected by the ellipsoid. The above characteristics of the ellipsoid can be well applied to the light emitting device. However, due to the high processing cost of the ellipsoid and the difficulty in ensuring the processing accuracy, the effect is not ideal in actual production and application due to assembly errors and other reasons.

[0033] Since the ellipsoid has problems in processing and assembly in practical applications, the applicant still used an easily available sphere, when the reflective surface 103 is a spherical surface that is easy to process. Wherein the line segment C is composed of the center point B of the light source 101 and the convergent light beam 122 at the exit focus A, and the length of the line segment C is L. After repeated experiments, the applicant concluded that when adjusting the distance between the sphere center O corresponding to the reflective surface 103 and the line segment C, it was found that the brightness of the convergent light beam 122 at the exit focus A will change after the first angle light 121 emitted by the center point B of the light source 101 is reflected by the reflective surface 103, and the sphere center O corresponding to the reflective surface 103 to the line segment C is obviously better than the sphere center O on the line segment C when it is within a certain value range.

[0034] In order to verify the above problem, the applicant's experimental data are as follows.

[0035] Table 1:

[0036]

[0037] In this experiment, the spherical radius corresponding to the reflecting surface 103 is R, the length of the line segment C is L, the ratio of the brightness of the convergent light beam 122 formed by the light emitted by the center point B of the light source 101 and reflected by the reflecting surface 103 at the exit focus A to the brightness of the light source 101 is defined as W, and the distance between the center of the sphere O and the line segment C is y.

[0038] In this experiment, the radius R of the sphere remains unchanged, and the length L of the line segment C remains unchanged. When the line segment C is slowly moved toward the direction close to the reflecting surface 103, according to the conservation of optical extension, the brightness of the convergent light beam 122 formed after the light emitted by the center point B of the light source 101 is reflected by the reflecting surface 103 is less than the brightness of the light at the center point B of the light source. Only when the reflecting surface 103 is smooth enough can the brightness at the exit focus A be the same as the brightness at the center point B of the light source 101. In actual design, we aim to make the brightness of the exit focus A close enough to the brightness of the center point B of the light source 101.

[0039] That is, starting from y=0, gradually increase the value of y and observe the change of W. During the experiment, the applicant found that when y=0, y=0 is the initial position from the center of the sphere O to the line segment C, and y is defined as V 初始值 , in this case, define W as W 初始值 As the line segment approaches the reflecting surface 103, y gradually increases, and W also gradually increases with the increase of y. When y reaches a certain value, W is close to 1. When W is close to 1, W is W. 最佳值 , the corresponding y is y 最佳值 ; When y continues to increase, W gradually begins to decrease until y reaches a certain value and the W obtained is equal to the W when y = 0. At this time, y is y 上限值 , W is W上限值 .

[0040] In summary, the distance from the center of the sphere O to the line segment C is y, y 初始值 <y<y 最佳值 When the corresponding W is greater than W 初始值 , when y=W 最佳值 When , the brightness at the exit focus A reaches its maximum.

[0041] In order to study the relationship between the spherical radius R corresponding to the reflecting surface, the length L of the line segment C and y, the applicant continued to conduct the following experiment:

[0042] Table 2:

[0043]

[0044] Combining Table 1 and Table 2, the center point B of the light source 101 is changed from y=0 (when y=0, it is when the center point B of the light source 101 and the line segment C are on the same straight line as pointed out by the personnel in the related technical field in the prior art, and is represented by the initial value of y in this embodiment)

[0045] The formula is obtained by fitting the experimental data:

[0046] When 0<y<y 上限值 , the ratio of the brightness of the exit focus A to that of the light source 101 is y 初始值 It is better when there is a W 最佳值 , y 上限值 Substitute the formula into the range of y, 0<y<y 上限值 get: The inequality is divided by R to get the range of y, Through experiments, we get y 最佳值 When Due to actual production and assembly errors, y 最佳值 In a certain range, a preferred embodiment is:

[0047]

[0048] In actual operation, it can be considered that when it is greater than y 上限值 When it is forty percent of y and less than sixty percent of the upper limit value of y, the ratio of the brightness of the convergent light beam 122 formed by the light emitted by the center point B of the light source 101 at the exit focus A to the brightness of the light source 101 is approximately equal to 1, and therefore they are all within the protection scope of this patent.

[0049] For example, in an ideal situation, the foot of the perpendicular from the center O to the line segment C is located at the midpoint of the line segment C. Since this is not an ideal situation, the foot of the perpendicular from the center O to the line segment C is located in the middle of the line segment C and still meets the condition. Therefore, in the present technical solution, it is pointed out that the foot of the perpendicular from the center O to the line segment C is located in the middle of the line segment C. From the above analysis, it can be seen that the y obtained according to the formula is an optimal value range. At this time, the position between the center point B of the light source 101 and the exit focus A does not have to be symmetrical about the center O. When the center point B of the light source 101 and the exit focus A are not symmetrical about the center O, the light emitted from the center point B of the light source 101 can also be reflected by the reflection surface 103 and then achieve an ideal convergence effect at the exit focus A.

[0050] According to the above disclosed technical solution, the light required by the light emitting device is the light of a partial angle from the light source 101. Only when the light source 101 emits light at a full angle can the light of the required angle be obtained from it. Figure 4 As shown, a preferred embodiment is that the light source 101 is an LED light emitting chip 101a, and the light emitting surface of the LED light emitting chip 101a is covered with a fluorescent material 101b. Since the LED light emitting chip 101a is a daily lighting device, it is easy to obtain and has a low price, so the LED light emitting chip 101a is selected, and the fluorescent material 101b is covered on the surface of the LED light emitting chip 101a, and the light emitted by the LED light emitting chip 101a is more uniform.

[0051] In summary, the technical solution provides a distance formula from the center O of the sphere to the line segment C between the center point B of the light source 101 and the emission focus A, and obtains the optimal distance range. This technical solution overcomes the technical bias in the prior art that the center O, the center point B of the light source 101 and the emission focus A are on the same straight line as the best position.

[0052] Example 2

[0053] LED chips are low-cost, easy to obtain, and convenient to use and install as light sources. However, LED chips are affected by their own power. In high-power lighting, the power of lighting is increased by increasing the number of LED chips. Since LED chips need to occupy a certain area, the more LED chips there are, the larger the area of ​​the light point will be, which affects the light angle and light spot of our light beam. Therefore, there are many problems with LED chips in high-power lighting. Figure 5As shown, a light emitting device, in order to solve the problem of high-power lighting, a preferred embodiment is that the light source is a fluorescent light emitting device 201, and also includes a laser light source 207 for exciting the fluorescent light emitting device 201, the laser light source 207 emits a laser 223, and the laser 223 excites the fluorescent light emitting device 201 and the fluorescent light emitting device 201 is excited to emit fluorescence. The fluorescent light emitting device 201 is a reflective fluorescent sheet, and the laser light source 207 is arranged on the side of the reflective surface 203 away from the reflective fluorescent sheet; a light hole 204 is arranged beside the reflective surface 203, and the laser 223 passes through the light hole 204 and excites the reflective fluorescent sheet.

[0054] The reflective fluorescent sheet emits light at all angles, so the present technical solution uses a reflective fluorescent sheet 201 to replace an LED light-emitting chip and is applied to high-power, long-distance lighting. The fluorescence emitted by the reflective fluorescent sheet includes a first angle light 221 that meets the requirements. Since the fluorescent light-emitting device 201 is a reflective fluorescent sheet, and the reflective fluorescent sheet emits light toward the reflective surface 203, the laser 223 is required to excite the reflective fluorescent sheet and not block the first angle light 221 emitted by the reflective fluorescent sheet. Therefore, the laser light source 207 is located on the side of the reflective surface 203 away from the reflective fluorescent sheet. Therefore, a light hole 204 is provided next to the reflective surface 203, and the laser 223 excites the reflective fluorescent sheet after passing through the light hole 204.

[0055] Example 3

[0056] like Figure 6 As shown, a light emitting device is provided. The difference between this embodiment and embodiment 1 is that the first angle light in embodiment 1 is small angle light, while the first angle light 321 in this embodiment is large angle light.

[0057] Example 4

[0058] like Figure 7 As shown, a light-emitting device, the difference between this embodiment and embodiment 3 is that the light source is a fluorescent light-emitting device 401, and also includes a laser light source 407 for exciting the fluorescent light-emitting device 401, the laser light source 407 emits a laser 423, and after the laser 423 excites the fluorescent light-emitting device 401, the fluorescent light-emitting device 401 is excited to emit fluorescence.

[0059] The fluorescent light emitting device 401 is a reflective fluorescent sheet, and the laser light source 407 is arranged on the side of the reflective surface 403 away from the reflective fluorescent sheet. A light hole 404 is arranged on the reflective surface 403, and the laser 423 excites the reflective fluorescent sheet after passing through the light hole 404.

[0060] In this embodiment, the light hole 404 is opened on the reflective surface 403. Although the laser 423 can pass through the light hole 404 to excite the reflective fluorescent sheet, part of the first angle light 421 will also be emitted from the light hole 404 to the outside of the light-emitting device, resulting in a waste of light and a low utilization rate of the reflective fluorescent sheet. A preferred embodiment is that a second reflective surface 406 is provided in the area corresponding to the opening of the light hole 404, and a part of the first angle light 426 emitted by the reflective fluorescent sheet reaches the second reflective surface 406 and is reflected back to the reflective fluorescent sheet by the second reflective surface 406, and the second reflective surface 406 is coated with a coating layer that transmits the laser 423 and reflects the fluorescence.

[0061] The second reflective surface 406 is fixedly disposed on the second lens 405, and the second reflective surface 406 prevents the first angle light 426 from being emitted from the light-through hole 404, thereby improving the utilization rate of the laser light emitted by the reflective fluorescent sheet. Since the second lens 405 is a concave lens and the lens 409 is a focusing convex lens, in order to make the laser light 423 emitted by the laser light source 407 still a focused light beam after passing through the lens 409 and the second lens 405, the curvature of the lens 409 is preferably greater than that of the second lens 405.

[0062] The light source is not only a laser light source 407 that excites the reflective fluorescent sheet, but a preferred embodiment is that the light source also includes an LED light-emitting chip that is close to the fluorescent light-emitting device 101. The fluorescent light-emitting device 101 is a transmissive fluorescent sheet. The transmissive fluorescent sheet is combined with the LED light-emitting chip, and the color rendering index of the light emitted is higher and the color reproduction is better.

[0063] Example 5

[0064] In an existing lighting device, if the light emitted by the light source is to be emitted within a certain angle range, the other part of the light that does not meet the angle range will be wasted. How to scatter and reflect the part of the light emitted by the light source that does not meet the use requirements and then re-emit the light within the required angle range. According to the knowledge of optics and geometry, when the reflecting surface is a spherical surface and the light source is located at the center of the spherical surface, it is possible to reflect the light that does not meet the use requirements back to the light source.

[0065] For example, in the patent application filed by Super Vision Laser Technology (Suzhou) Co., Ltd. on August 7, 2017, the light-emitting device and laser lighting lamp, application number: CN201710664717.X, Figure 2As shown, the application discloses that by setting a spherical reflective bowl as a reflective unit 30 and placing a wavelength conversion unit 20 at the center of the sphere, a part of the fluorescence excited by the laser beam projected onto the transmission type fluorescent layer 210 is directly emitted from the second light hole 320, and the other part is still projected onto the wavelength conversion unit 20 for re-excitation after being reflected by the reflective unit 30, and a part of the re-excited light will be directly emitted from the second light hole 320, and the other part of the light will be reflected by the reflective unit 30 for multiple times and excited by the wavelength conversion unit 20 for multiple times, and finally all the excited light will be emitted from the second light hole 320. In this way, not only can the fluorescence be effectively prevented from being emitted from the edge of the reflective unit 30 in a non-specified direction, but the light can also enhance the central brightness after multiple excitations, thereby improving the safety performance and the utilization rate of the light source.

[0066] This prior art utilizes the property that light emitted from the center of a sphere is reflected by the spherical surface and then returns to the center of the sphere. However, the light source in actual operation is not an ideal point light source, so when the reflecting surface is a spherical surface and the light source is located at the center of the spherical surface, the effect of recycling this part of light is not ideal.

[0067] like Figure 8 As shown, a light emitting device includes a light source 501 having a light emitting surface and a spherical reflector 502 with a radius of R, the center of the spherical reflector 502 is O, the concave surface of the spherical reflector 502 is a reflective surface 503, the light emitting surface emits light toward the reflective surface 503, the diameter of the circumscribed circle of the light emitting surface is L, the foot of the perpendicular from the center O to the light emitting surface is located at the center of the light emitting surface, the light emitting surface is located between the center O and the reflective surface 503, the distance from the geometric center C of the light emitting surface to the center O is y, and the

[0068] In the prior art, the light-emitting device and laser lighting lamp, application number: CN201710664717.X, discloses that by setting a spherical reflective bowl as a reflection unit and placing a wavelength conversion unit at the center of the sphere, a portion of the fluorescence excited by the laser beam projected onto the transmission-type fluorescent layer is directly emitted from the second light hole, and the other portion is still projected onto the wavelength conversion unit for re-excitation after being reflected by the reflection unit. This technology requires a theoretical point light source to emit light to the spherical surface at the center of the spherical surface to realize that the light emitted by the light source is reflected by the spherical surface and returns to the light-emitting point of the light source. However, in actual applications, the light source is not an ideal point light source, so the light emitted from the center of the sphere will not completely return to the center of the sphere after being reflected by the spherical surface. At this time, the utilization rate of the light that can be emitted by the light source is significantly lower than that in theory. After discovering the above problem, the applicant conducted multiple experiments and found that changing the distance between the light source's luminous surface and the spherical surface can improve the utilization rate of the light emitted by the light source.

[0069] The applicant obtained the above formula after conducting the following experiment. The applicant's experimental data are as follows.

[0070]

[0071] In order to solve this technical problem, the technical solution adjusts the distance between the light-emitting surface and the reflective surface 503 to ensure that as much light as possible emitted by the light-emitting surface is reflected by the reflective surface 503 and then returns to the light-emitting surface.

[0072] During the experiment, the light-emitting surface was slowly moved from y=0 (when y=0, it means that the light source is located at the center of the sphere O as pointed out by the personnel in the related technical field in the prior art) as the starting point toward the direction close to the reflecting surface 503. During the experiment, the applicant found that when the light source approaches the reflecting surface 503 from y=0, the brightness of the light spot of the light emitted by the light-emitting surface after being reflected by the reflecting surface 503 and returning to the light-emitting surface gradually increases. When y reaches a certain value range, the brightness of the light spot of the light emitted by the light-emitting surface after being reflected by the reflecting surface 503 and returning to the light-emitting surface reaches a peak. When y continues to increase, the brightness of the light spot of the light emitted by the light-emitting surface after being reflected by the reflecting surface 503 and returning to the light-emitting surface gradually begins to decrease until y reaches the upper limit value. At this time, the brightness of the light spot of the light emitted by the light-emitting surface after being reflected by the reflecting surface 103 and returning to the light-emitting surface is the same as when y=0.

[0073] When the applicant analyzed the upper limit value of y in the table, he found that Figure 8 In the dimension shown, the brightness of the light spot of the first angle light 521 emitted by the light emitting surface after being reflected by the reflective surface 503 and returning to the light emitting surface reaches the maximum. Since the reflective surface 503 is a spherical surface, at this time, Figure 3 In the vertical dimension, the brightness of the light spot of the first angle light 521 reflected by the reflective surface 503 on the light-emitting surface becomes very small, so when y is at its upper limit, the position of the light-emitting surface is not at the optimal position. During the experiment, the brightness of the light spot formed by the first angle light 521 reflected by the reflective surface 503 on the light-emitting surface is analyzed to obtain an optimal y value, as shown in the fifth column of the table. According to the comparison between the optimal y value and the upper limit of y, it can be seen that the optimal y value is approximately half of the upper limit of y.

[0074] The formula is obtained by fitting the experimental data

[0075] Since the formula is obtained by fitting the data, the y obtained by the formula is not a specific value, but an approximate range. It can only be said that when the above formula is satisfied, the light emitted by any point on the light-emitting surface of the light source 501 is reflected by the reflecting surface 503 and then returns to the light-emitting surface. A preferred embodiment is that This technical solution enables the light emitted by the light source 501 to be reflected by the reflective surface 503 and then reflected back to the light-emitting surface as much as possible.

[0076] For example, in an ideal situation, the foot of the perpendicular from the center O to the light-emitting surface is located at the midpoint of the light-emitting surface. Since this is not an ideal situation, the foot of the perpendicular from the center O to the light-emitting surface is located at the center of the light-emitting surface and still meets the condition. Therefore, it is pointed out in the present technical solution that the foot of the perpendicular from the center O to the light-emitting surface is located at the center of the light-emitting surface. From the above analysis, it can be seen that the y obtained according to the formula is an optimal range of values. The light-emitting surface has a certain area and will not be like a point light source. Once it deviates, it will not be able to receive the light reflected by the reflective surface 503. Therefore, the center of the light-emitting surface and the foot of the perpendicular from the center O to the light-emitting surface do not have to coincide. When the foot of the perpendicular from the center O to the light-emitting surface is at the center of the light-emitting surface, it can still ensure that a large part of the light reflected by the reflective surface 503 returns to the light-emitting surface.

[0077] The light emitted by the light source 501 is not completely reflected by the reflective surface 503 and then returned to the light-emitting surface. A preferred embodiment is that it also includes a light emitting portion 510, and the light emitting portion 510 includes a third reflective surface 511. The first angle light 521 emitted by the light-emitting surface is emitted after being reflected by the third reflective surface 511, and the reflective surface 503 covers the second angle light 522 emitted by the light-emitting surface. The first angle light 521 that cannot be reflected by the reflective surface is emitted after being reflected by the third reflective surface 511.

[0078] According to the above disclosed technical solution, the light required by the light emitting device is the light of a partial angle in the light source 501. Only when the light source 501 emits light at a full angle can the light of the required angle be obtained therefrom. A preferred embodiment is that the light source 501 is an LED light emitting chip, and the light emitting surface of the LED light emitting chip is covered with a fluorescent material. Since the LED light emitting chip is a daily lighting device, it is easy to obtain and the price is low, so the LED light emitting chip is selected, and the fluorescent material is covered on the surface of the LED light emitting chip, and the light emitted by the LED light emitting chip is more uniform.

[0079] Example 6

[0080] like Fig. 9 As shown, the difference between this embodiment and embodiment 5 is that the second angle light in embodiment 5 is a large angle light emitted by the light source, while the second angle light 622 in this embodiment is a small angle light. Fig.10 As shown, when the second angle light 622 is at a small angle, the reflective surface 603 and the third reflective surface 611 may not be spliced ​​into one piece. In this embodiment, the reflective surface 603 is arranged opposite to the light source 601, and the third reflective surface 611 is arranged around the light source 601.

[0081] Several embodiments of the present invention are described in detail above, but the contents are only preferred embodiments of the present invention and cannot be considered to limit the scope of implementation of the present invention. The various features in the above embodiments can also be freely combined, for example, the light source of embodiment 5 and embodiment 6 can also adopt the laser excitation fluorescence light emitting device introduced in embodiment 2 and embodiment 4.

[0082] All equivalent changes and improvements made within the scope of the present invention should fall within the patent scope of the present invention.

Claims

1. A light emitting device, characterized in that: The invention comprises a light source with a center point B and a spherical reflector with a radius R and a center O, wherein the concave surface of the spherical reflector is a reflecting surface, the light source emits light toward the reflecting surface, and the light is reflected by the reflecting surface to form a converging light beam, which converges at an exit focus A, the length between the center point B of the light source and the exit focus A is L, the line connecting the exit focus A and the center B of the light source is a line segment C, the foot of the perpendicular from the center O to the line segment C is located in the middle of the line segment C, the line segment C is located between the center O and the reflecting surface, the distance from the center O to the line segment C is y, and the 2. A light emitting device according to claim 1, characterized in that: Said 3. A light emitting device according to claim 1, characterized in that: The light source is an LED light-emitting chip, and the light-emitting surface of the LED light-emitting chip is covered with fluorescent material.

4. A light emitting device according to claim 1, characterized in that: The light source is a fluorescent light-emitting device, and also includes a laser light source for exciting the fluorescent light-emitting device. The laser light source emits laser light, and after the laser excites the fluorescent light-emitting device, the fluorescent light-emitting device is excited to emit fluorescence.

5. A light emitting device according to claim 4, characterized in that: The fluorescent light-emitting device is a reflective fluorescent sheet, and the laser light source is arranged on the side of the reflective surface away from the reflective fluorescent sheet; a light hole is arranged on or beside the reflective surface, and the laser excites the reflective fluorescent sheet after passing through the light hole.

6. A light emitting device according to claim 5, characterized in that: A second reflective surface is provided corresponding to the area where the light-through hole is opened. A portion of the first angle light emitted by the reflective fluorescent sheet reaches the second reflective surface and is reflected back to the reflective fluorescent sheet by the second reflective surface. The second reflective surface is coated with a coating layer that transmits laser and reflects fluorescence.

7. A light emitting device according to claim 4, characterized in that: The light source also includes an LED light emitting chip which is closely attached to the fluorescent light emitting device.

8. A light emitting device, comprising a light source having a light emitting surface and a spherical reflector with a radius R, characterized in that: The center of the spherical reflector is O, the concave surface of the spherical reflector is the reflective surface, the luminous surface emits light toward the reflective surface, the diameter of the circumscribed circle of the luminous surface is L, the foot of the perpendicular from the center O to the luminous surface is located at the center of the luminous surface, the luminous surface is located between the center O and the reflective surface, the distance from the geometric center C of the luminous surface to the center O is y, 9. A light emitting device according to claim 8, characterized in that: It also includes a light emitting portion, which includes a third reflecting surface. The first angle light emitted by the light emitting surface is reflected by the third reflecting surface and then emitted. The reflecting surface covers the second angle light emitted by the light emitting surface.

10. A light emitting device according to claim 8, characterized in that: Said 11. A light emitting device according to claim 8, characterized in that: The light source is an LED light emitting chip, and the light emitting surface of the LED light emitting chip is covered with fluorescent material.

12. A light emitting device according to claim 8, characterized in that: The light source is a fluorescent light-emitting device, and also includes a laser light source for exciting the fluorescent light-emitting device. The laser light source emits laser light, and after the laser excites the fluorescent light-emitting device, the fluorescent light-emitting device is excited to emit fluorescence.

13. A light emitting device according to claim 12, characterized in that: The fluorescent light-emitting device is a reflective fluorescent sheet, and the laser light source is arranged on the side of the reflective surface away from the reflective fluorescent sheet; a light hole is arranged on or beside the reflective surface, and the laser excites the reflective fluorescent sheet after passing through the light hole.

14. A light emitting device according to claim 13, characterized in that: A second reflective surface is provided corresponding to the area where the light-through hole is opened. A portion of the first angle light emitted by the reflective fluorescent sheet reaches the second reflective surface and is reflected back to the reflective fluorescent sheet by the second reflective surface. The second reflective surface is coated with a coating layer that transmits laser and reflects fluorescence.

15. A light emitting device according to claim 12, characterized in that: The light source also includes an LED light emitting chip which is closely attached to the fluorescent light emitting device.

16. A lamp, characterized in that: A light-emitting device comprising any one of claims 1-15.

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