CN116549867A

CN116549867A - Light feeding equipment

Info

Publication number: CN116549867A
Application number: CN202211665719.8A
Authority: CN
Inventors: 吴丹磊; 陈荡荡; 和超
Original assignee: Beijing Yingtong Mingmu Information Technology Co ltd; Beijing Airdoc Technology Co Ltd
Current assignee: Beijing Yingtong Medical Technology Co ltd; Beijing Yingtong Mingmu Information Technology Co ltd; Beijing Airdoc Technology Co Ltd
Priority date: 2022-12-09
Filing date: 2022-12-23
Publication date: 2023-08-08
Also published as: CN219185642U; CN116212251A; CN219185643U; CN219398737U; CN116195965A; CN116139414A

Abstract

The present disclosure discloses a nursing device. The light feeding device comprises: a red light source operative to generate red light for illuminating a fundus of a user; and a projection light path comprising a front set of elements and a rear set of elements and operative to receive red light and project the red light to the fundus of the user, wherein the front set of elements comprises a diffractive optical element device and a projection mirror disposed at an entrance end of the diffractive optical element device, and the rear set of elements comprises a conjugate mirror disposed at an exit end of the diffractive optical element device, wherein the diffractive optical element device is operative to deflect the red light in a direction such that the projection light path projects a spot at a predetermined region of the fundus of the user. Through the scheme of the disclosure, personalized and accurate red light irradiation can be provided, and meanwhile, the optical conjugation technology is utilized to ensure the light power of the eye-feeding light so as to realize efficient red light irradiation, thereby effectively improving the light feeding effect on human eyes.

Description

Light feeding equipment

Technical Field

The present disclosure relates generally to the field of optical projection and imaging technology. More particularly, the present disclosure relates to a light feeding device.

Background

Eye axis growth is one of the major factors responsible for myopia in the human eye, especially for young people in rapid onset of age. Researches show that the long-wave red light of 650 nanometers (nm) is directly irradiated on the retina, so that the increase of the length of the eye axis can be effectively inhibited. Therefore, the irradiation of retina with red light has a positive effect on the prevention and control of myopia in teenagers.

There are some nursing devices currently on the market for myopia prevention and control. Such devices typically employ a dual barrel construction, one for each eye. Through the setting of mechanical structure, can adjust the interval between the binocular in order to adapt to the position of people's eye to the red light image coincidence that makes both eyes see. For illustrative purposes only, fig. 1 shows the basic light path structure of such a nursing device in the case of a single barrel. As shown in fig. 1, after exiting from the red light source, the red light enters the human eye through the light transmitting element and irradiates on the retina. In terms of selection and setting of the red light source, the red light source is generally selected as an LED light source or a laser light source having a wavelength around 650 nm. In addition, the light-transmitting element may be a transparent protective window plate or may be a light-transmitting lens to further converge or diverge the light beam emitted by the light source.

The working principle of the red light irradiation in the light feeding device is that the red light in the 650nm wave band has strong penetrability, and the red light simultaneously acts on the choroid after penetrating the retina. Since 650nm red light has a warming effect, bottleneck-like stenosis at the arteriole opening of the choroidal leaflet is opened, and blood flow into the leaflet is increased, thereby increasing microcirculation blood volume. Because the choroid thickness is increased without hypoxia of the sclera, the thinned choroid can be restored to normal thickness, sufficient oxygen is provided for the sclera and blood circulation of the fundus is improved, and myopia degree is not increased. In addition, 650nm red light can enable retinal epithelial pigment cells to secrete dopamine, so that excessive increase of an eye axis is effectively inhibited.

Although having remarkable effect on myopia prevention and control, the current light-feeding technology has some obvious defects. In particular, the currently commonly used red light source is a similar point light source, whether it is a light emitting LED or a laser diode, so that the light emitting area is small. When looking directly at the light source or observing the light source image after lens transformation, the human eye adjusts the central concave to face the light source itself, and sees a circular spot with higher central brightness, as shown in fig. 2. When the eye adjusts the photopic position to make the light source image clear, the size of the central bright spot is reduced, and the brightness of the bright spot is further increased, so that the visual stimulus to the eye is increased and the eye is further uncomfortable.

In addition to the fact that the smaller size of the light source causes stronger visual stimuli from the direct-view light source, this approach has a negative impact. That is, when more red light energy is concentrated in the center of the macular region, the red light energy of the peripheral macular region is very weak. Thus, the illumination of the choroid in the macular area is unevenly stimulated, which in turn results in warming and uneven stimulation of the choroid, which ultimately affects the practical effect of red light irradiation to inhibit eye axis growth.

In view of this, how to provide a light feeding scheme for precisely irradiating a predetermined area of the fundus becomes a technical problem to be solved currently.

Disclosure of Invention

In order to address at least one or more of the technical problems mentioned above, the present disclosure, in various embodiments, proposes a light-feeding device that may effectively enhance the light-feeding effect to the human eye.

In particular, the present disclosure provides a light feeding apparatus including a red light source operative to generate red light for illuminating a user's fundus; and a projection light path comprising a front set of elements and a rear set of elements and operative to receive the red light and to project the red light towards the user's fundus, wherein the front set of elements comprises a diffractive optical element device and a projection mirror arranged at an entrance end of the diffractive optical element device, the rear set of elements comprises a conjugate mirror arranged at an exit end of the diffractive optical element device, wherein the diffractive optical element device is operative to deflect the red light in a direction such that the projection light path projects a spot at a predetermined region of the user's fundus.

In one embodiment, the predetermined region of the user's fundus comprises a predetermined region of the macular region, wherein the predetermined region is divided according to the angle of the macular region.

In yet another embodiment, the light spot projected at the predetermined region of the user's fundus comprises a circular light spot or an annular light spot.

In an embodiment, wherein the positions of the projection mirror and conjugate mirror in the projection light path are arranged such that the position of the diffractive optical element device that deflects the red light in the direction forms an optical conjugate with the user pupil position.

In another embodiment, the conjugate mirror is arranged between the exit end of the diffractive optical element device and the fundus of the user so that the position of the diffractive optical element device that deflects the red light in the direction forms an optical conjugate with the pupil position of the user.

In yet another embodiment, wherein the back focal point of the conjugate mirror is located at the pupil of the user and the projection mirror is operative to focus the red light from the red light source onto the projection mirror to focus at the front focal plane of the conjugate mirror.

In one embodiment, the projection light path further comprises the fixation light source operative to illuminate the projection light path for directing the user to fixate on the spot center.

In another embodiment, an intermediate image plane is formed at a front focal point of the conjugate mirror, and the projection optical path includes: a beam splitter disposed between the diffractive optical element device and the intermediate image plane, or between the intermediate image plane and the conjugate mirror, for receiving a light beam from a fixation light source to achieve optical conjugation of the fixation light source with a pupil position of a user.

In a further embodiment, a fixation point is formed in the projected light path for guiding the user to look at the centre of the spot.

In an embodiment, wherein the microstructure of the diffractive optical element device is arranged to retain a predetermined proportion of the 0 th order diffracted light at the primary angle of incidence to produce the fixation point.

In another embodiment, the spots have different preset patterns according to different projection requirements, and each preset pattern corresponds to a micro-nano structured diffraction optical element device.

In yet another embodiment, further comprising: and the switching mechanism is operated to switch one of the diffraction optical element devices with the corresponding micro-nano structure into the projection light path according to different projection requirements.

In one embodiment, the apparatus further comprises a drive mechanism operative to perform at least one of the following drive to effect refractive compensation of the user's human eye by focusing: driving the conjugate mirror to move relative to an intermediate image plane formed at a front focal point of the conjugate mirror; and driving the red light source, the projection mirror and/or the diffractive optical element device to move relative to an intermediate image plane formed at a front focal point of the conjugate mirror.

In one embodiment, the optical system further comprises a fixation projection mirror operative to project a light beam from the fixation light source at the intermediate image plane position in a lens projection manner, the driving mechanism operative to drive the projection mirror and the diffractive optical element device to move relative to the intermediate image plane formed at the front focal point of the conjugate mirror.

With the light feeding apparatus provided above, embodiments of the present disclosure utilize a diffractive optical element device ("DOE") to angularly deflect incident red light while maintaining the directionality of its laser light, thereby enabling an annular spot to be projected at the fundus of a user while utilizing a projection mirror and a conjugate mirror to form a conjugate mirror group. Therefore, the scheme of the disclosure can enable the annular light spot projected on the fundus of the user to form red light annular energy distribution of a specific peripheral macular area avoiding the central concave of the macular area, and meanwhile, the optical conjugation technology is utilized to ensure the light power of the light for feeding eyes, so that efficient red light irradiation is realized, and the light feeding effect on the eyes of the user is effectively improved.

Further, in some embodiments, by utilizing the DOE itself or the fixation point provided by the fixation light source, the user may be guided to look at the red light, thereby achieving a better illumination effect. In addition, by utilizing the fixation point provided by the DOE itself, the use of fixation light sources can be avoided, thereby reducing the cost and complexity of the device. In addition, by utilizing a drive mechanism, movement of the associated components in the disclosed light feeding apparatus may be driven to effect refractive compensation and determination of the base diopter of the human eye to facilitate detection of diopter.

Drawings

The above, as well as additional purposes, features, and advantages of exemplary embodiments of the present disclosure will become readily apparent from the following detailed description when read in conjunction with the accompanying drawings. Several embodiments of the present disclosure are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar or corresponding parts and in which:

FIG. 1 shows a schematic optical path diagram of a prior art light feeding device;

FIG. 2 shows a red light visual effect and energy distribution diagram of a prior art light feeding device;

FIG. 3 shows a schematic optical path diagram of a light feeding device of the present disclosure;

FIG. 4 shows a red light visual effect and energy distribution diagram of a light feeding device of an embodiment of the present disclosure;

FIG. 5 shows a schematic optical structure of a nursing device of one embodiment of the present disclosure;

FIG. 6 shows a schematic optical structure of a nursing device of another embodiment of the present disclosure;

FIG. 7 shows a schematic optical structure of a nursing device of yet another embodiment of the present disclosure;

FIG. 8 illustrates a schematic diagram of adjusting focus to achieve human eye diopter compensation according to one embodiment of the present disclosure;

FIG. 9 illustrates a schematic diagram of adjusting focus to achieve eye diopter compensation according to another embodiment of the present disclosure;

FIG. 10 shows a schematic optical structure of a switchable DOE nursing device of an embodiment of the present disclosure; and

fig. 11 illustrates various exemplary diagrams of annular spots of embodiments of the present disclosure.

Detailed Description

The following description of the embodiments of the present disclosure will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are some, but not all embodiments of the disclosure. Based on the embodiments in this disclosure, all other embodiments that may be made by those skilled in the art without the inventive effort are within the scope of the present disclosure.

It should be understood that the terms "comprises" and "comprising," when used in this specification and the claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

It is also to be understood that the terminology used in the description of the present disclosure is for the purpose of describing particular embodiments only, and is not intended to be limiting of the disclosure. As used in the specification and claims of this disclosure, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should be further understood that the term "and/or" as used in the present disclosure and claims refers to any and all possible combinations of one or more of the associated listed items, and includes such combinations.

As used in this specification and the claims, the term "if" may be interpreted as "when..once" or "in response to a determination" or "in response to detection" depending on the context. Similarly, the phrase "if a determination" or "if a [ described condition or event ] is detected" may be interpreted in the context of meaning "upon determination" or "in response to determination" or "upon detection of a [ described condition or event ]" or "in response to detection of a [ described condition or event ]".

Specific embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

Exemplary application scenarios

The prior art light-feeding treatment apparatus generally employs a basic light path structure as shown in fig. 1, which is not ideal for the light-feeding effect of the human eye. The inventor finds through analysis and research that a key factor affecting the light feeding effect of the existing light feeding treatment equipment is that light source energy sources in human eyes are too concentrated and unevenly distributed. As described in the foregoing background, the light source in the light-feeding therapeutic apparatus has a small light-emitting area, and when looking directly at the light source or observing the light source image after lens conversion, the human eye adjusts the fovea to face the light source itself, and sees a circular spot with a high central brightness as shown in fig. 2. When the eye adjusts the photopic position to make the light source image clear, the size of the central bright spot can be reduced, and the brightness of the bright spot can be further increased, and the visual stimulus is increased to cause discomfort to the eye. In addition, the light source energy is distributed more intensively in the center of the macular region of the human eye, and is distributed weaker in the peripheral macular region. Thus, when the illumination stimulus to the choroid in the macular area is uneven, this in turn results in a warming effect and uneven stimulus to the choroid, and finally affects the actual effect of the red light irradiation to suppress the increase of the ocular axis.

To this end, the inventors have studied to find that it is possible to construct a scheme capable of red irradiation of a predetermined region of a user's fundus, thereby providing a flexible, efficient and personalized (or customized) nursing operation, thereby overcoming various technical drawbacks such as uneven irradiation, which exist in the prior art. Through the innovative nursing scheme of the present disclosure, the targeted irradiation of the predetermined region corresponding to the predetermined region of the fundus can be realized by utilizing the red light pattern corresponding to the predetermined region, thereby achieving the effective and efficient nursing of the human eye. For example, in some scenarios, depending on the nursing needs of the user, the nursing scheme of the present disclosure may project red light spots with a circular pattern to the fundus of the user, thereby obtaining a uniform nursing effect with evenly distributed red light energy. In other scenarios, the fostering scheme of the present disclosure may be capable of projecting a new fostering device of annular light spots at the fundus of a user to achieve a red annular energy distribution of a specific peripheral macular region that avoids the fovea of the macular region, thereby obtaining a customized fostering effect for a specific area.

Exemplary light feeding device scheme

In view of the above, embodiments of the present disclosure provide a light-feeding apparatus that can project a spot at a predetermined area of a user's fundus by angularly deflecting incident red light while maintaining the directionality of its laser light using a DOE device, and simultaneously introduce a projection mirror and a conjugate mirror to form a conjugate mirror group. In a scenario where the spot is annular, aspects of the present disclosure may cause the spot projected on the user's fundus to form a red annular energy distribution of a particular peripheral macular region that avoids the fovea of the macular region. In addition, the optical conjugation technology is utilized to ensure the light power of the light fed into eyes (particularly the preset area of the eyeground), so that the efficient red light irradiation is realized, and the light feeding effect on human eyes is effectively improved.

FIG. 3 shows a schematic optical path diagram of a nursing device of an embodiment of the present disclosure. As shown in fig. 3, a nursing device 301 may include a red light source 302 and a transmission light path 303. In one exemplary embodiment, the transmission light path 303 may include a front set of elements and a rear set of elements. As an example, the front set of elements illustratively includes a projection mirror 304 and a DOE device 305, and the rear set of elements illustratively includes a conjugate mirror 306. From a reading of the context, it will be appreciated that the projected optical path of the present disclosure may add additional optics depending on the application requirements, build an optical path suitable for the innovative principles of the present disclosure or make changes to the exemplary optical path structure of the present disclosure, while still falling within the scope of the present disclosure. In addition, for clarity of illustration of the optical path principle of the nursing device, the user's human eye (or fundus) 307 is also schematically shown in fig. 3.

For ease of understanding, fig. 3 further illustrates a human eye fundus structure. In particular, the figure shows the angular distribution of the macular region of the fundus. For example, it has an angular distribution of 15 degrees for all macular regions; for the peripheral macular area, it has an angular distribution of 8 degrees; for the fovea, it has an angular distribution close to 5 degrees. For such angular distribution, the micro-nano structure of the DOE device may be tailored accordingly to produce, when introduced into the projection optical path of the present disclosure, a spot corresponding to the aforementioned region of the specific angular distribution of the macular region. With respect to custom fabrication of DOE device micro-nano structures, it is within the scope of the prior art. This application does not describe this too much in order to avoid unnecessarily obscuring aspects of the present disclosure.

Specifically, the aforementioned red light source 302 operates to generate red light for illuminating the fundus of the user. In some implementations, the red light source 302 may employ a laser diode or other electronic device capable of producing a coherent light source. It should be noted that the specific type of the red light source is not limited in this disclosure, and may be selected according to actual requirements.

In use, the projection light path 303 described above may be operable to receive red light and project the red light toward the fundus of a user. To this end, the projection optical path of the present disclosure may specifically include a front set of elements such as projection mirror 304 and DOE device 305, and a rear set of elements such as conjugate mirror 306. In one embodiment, based on the physical characteristics and functionality of the DOE device 305, it may be precisely operable to directionally deflect the aforementioned red light so that the projected optical path may project a spot having a predetermined pattern on the user's fundus 307 that corresponds to a predetermined region of the fundus (e.g., the macular region). For this purpose, a specific directional deflection of the red light can be obtained, for example, by processing the micro-nano structure of the DOE device for specific requirements.

Further, the illustrated projection lens 304 may be disposed at an incident end of the diffractive optical element device, and the conjugate lens 306 (which may include a single-piece or multi-piece lens structure, in particular) may be disposed at an exit end of the diffractive optical element device. In projection light path 303, projection lens 304 and conjugate lens 306 may form a conjugate lens group to ensure the optical power of the feed light entering the eye using optical conjugation techniques. In some embodiments, the positions of the projection mirror 304 and conjugate mirror 305 in the projection light path 303 are arranged such that the position where the diffractive optical element device deflects the red light in the direction forms an optical conjugate with the user's pupil position. For example, the projection mirror 304 may be operable to project and focus the red light emitted by the red light source 302 to converge to a focal point at the front focal plane of the conjugate mirror 306, and at this point the back focal point of the conjugate mirror 306 may be located at the pupil of the user. Thus, the conjugate lens group formed by the projection lens 304 and the conjugate lens 306 can make the position of the diffraction optical element device for deflecting the red light in the direction and the pupil position of the user form optical conjugation, thereby ensuring the feeding light rate of the human eye 307.

It can be seen that the aforementioned light feeding device 301 can provide a desired spot pattern of light spots projected onto a predetermined area of the fundus of a user. For example, for an annular spot, it may create a red annular energy distribution of light during the nursing process that avoids a specific peripheral macular region of the fovea of the macular region. For another example, for a circular spot, it may create a uniform red light energy distribution throughout the macular area during the nursing process. Through such individuation nursing operation, the scheme of the disclosure utilizes the optical conjugation technology to ensure the nursing light power of the eye to realize efficient red light irradiation, thereby effectively improving the accurate control and the nursing effect of the nursing light to the eyes of the human.

Further, a fixation point may be formed in the projection light path, which is used for guiding the user to look at the center of the light spot, and the fixation point may be formed in various ways. In some embodiments, the present disclosure proposes to provide a separate fixation light source in the projection light path. The fixation point is formed by irradiating the projection optical path with the fixation light source. In practical applications, the fixation light source may be the same light source as the red light source 302, or may be a light source of a color different from red light, such as green, blue, etc., so that the human eye is more likely to focus on the spot center. It should be noted that, the fixation light source of the present disclosure may be set according to different application scenarios and/or user preferences, for example, may be set at different positions of the projected light path or set to emit light of different colors, so that flexible light path arrangement and different user experiences may be achieved.

For illustrative purposes only, the energy distribution of an annular spot with a fixation point is shown in fig. 4, wherein a fixation light source acts in the projected light path to form one spot in the middle of the annular region (in the middle of the fovea of the macular area in the figure) for fixation function, and wherein curve 1 indicates the energy distribution of the fovea and curve 2 indicates the energy distribution of the peripheral region of the macular area. It can be seen that when the user gazes at the annular spot, the user may gaze at the center of the annular spot under the guidance of the fixation light source, and the annular spot projected on the fundus 307 of the user may avoid the central recess of the macular region and be uniformly distributed in the peripheral macular region. Therefore, high-efficiency red light irradiation can be realized, and meanwhile, the stimulation of vision caused by the concentration of energy in a central concave part can be avoided, and the annular light spots distributed on the periphery based on the energy can generate uniform illumination stimulation on the veins of a macular region, so that the warm effect and the uniform stimulation on the choroid are ensured, and the effective light-feeding treatment on human eyes is realized.

Similar to the annular light spot, the DOE device micro-nano structure can be adjusted to generate a circular light spot through a projection light path, so that the circular light spot can be projected on the whole peripheral macular area with the angle distribution of 8 degrees, and the peripheral macular area can be provided with feeding light with red light energy uniformly distributed. It will be appreciated that a specific region (e.g., within 7 degrees) within the peripheral macular region may also be uniformly illuminated, and thus the aspects of the present disclosure are not limited by the scope of fundus illumination, but rather may be directed as desired.

In other embodiments, the DOE device itself may also be utilized to form the aforementioned fixation point. In some embodiments, the fixation point may be generated by modification of the microstructure of the diffractive optical element device. In particular, the microstructure of the diffractive optical element device may be arranged to retain a predetermined proportion of the 0 th order diffracted light at the original angle of incidence to produce the aforementioned fixation point.

FIG. 5 shows a schematic optical structure of a nursing device of one embodiment of the present disclosure. It will be appreciated that FIG. 5 is a specific implementation of the light device of FIG. 3. Accordingly, the foregoing detailed description in connection with fig. 3 applies equally as well to the following.

In this embodiment, the nursing device may include a red light source, a projection lens, a DOE device, a second conjugate mirror. The aforementioned red light source may generate red light for illuminating the fundus of the user. The projection light path formed by the projection mirror, the DOE device and the second conjugate mirror may receive the red light and project the red light to the fundus of the user. As described above, the DOE device can be precisely operated to deflect the aforementioned red light in a direction such that the projected light path can project a corresponding spot in a predetermined region of the fundus of the user. For this purpose, as previously described, a specific directional deflection of the red light can be obtained by processing the micro-nano structure of the DOE device for specific requirements.

In the projection light path, the projection mirror is operable to project and converge red light emitted by the red light source and converge to a focal point at a front focal plane of the conjugate mirror, and a back focal point of the conjugate mirror is located at the pupil of the user. Therefore, the conjugate lens group formed by the projection lens and the second conjugate lens can enable the position of the DOE device for deflecting the red light in the generation direction to form optical conjugation with the pupil position of a user, so that the feeding power entering human eyes is ensured.

FIG. 6 shows a schematic optical structure of a nursing device of another embodiment of the present disclosure. It will be appreciated that FIG. 6 is another specific implementation of the light device of FIG. 3. Accordingly, the foregoing detailed description in connection with fig. 3 applies equally as well to the following. Further, it is different from fig. 5 in that fig. 5 can form a fixation point for guiding the user to look at the center of the annular spot by the DOE device itself, whereas in fig. 6 of the present embodiment, a fixation point for guiding the user to look at the center of the spot can be formed by the fixation light source.

As shown in fig. 6, the nursing device may include a red light source, a projection lens, a DOE device, a second conjugate lens, and a fixation light source. The aforementioned red light source may generate red light for illuminating the fundus of the user. The projection light path formed by the projection mirror, the DOE device and the second conjugate mirror may receive the red light and project the red light toward the fundus of the user. The DOE device can precisely operate to deflect the red light in the direction, so that the projection light path can project a light spot with a preset pattern on the fundus of a user. In the projection light path, the projection lens is operable to converge red light from the red light source to a focal point at a front focal plane of the second conjugate lens, and a back focal point of the second conjugate lens is located at the pupil of the user. Therefore, the conjugate lens group formed by the projection lens and the second conjugate lens can enable the position of the DOE device for deflecting the red light in the generation direction to form optical conjugation with the pupil position of a user, so that the feeding power entering human eyes is ensured.

Further, in fig. 6, an intermediate image plane is formed at the front focal point of the second conjugate mirror. The projection light path further includes a beam splitter disposed between the DOE device and the intermediate image plane to receive the light beam from the fixation light source to achieve optical conjugation of the fixation light source with the pupil location of the user. In other embodiments, the position of the beam splitter can be adjusted according to design requirements. For example, as shown in fig. 7, the beam splitter may be disposed between the aforementioned intermediate image plane and the second conjugate mirror to achieve optical conjugation of the fixation light source to the pupil location of the user.

It should be noted that fig. 7 is understood to be a further specific implementation of the light feeding device in fig. 3, and the working principle of the light feeding device is the same as that of fig. 6, and the difference is only that the positions of the beam splitter and the fixation light source are different. For example, it is preferable to use a point light source of a color other than red light as the fixation light source, and introduce the fixation light source into the main optical path by using a spectroscope, and penetrate the second conjugate penetration into the human eye. In the application scene, the spectroscope is used for transmitting red light of a main light path and reflecting one path of a fixation light source so as to realize the beam combination of two beams of light. In terms of the setting of the position, the fixation light source may be arranged at the front focal point of the second conjugate mirror so as to be optically conjugate with the fundus. In some implementations, the beam splitter may include a dichroic mirror that splits light at a wavelength or a beam splitter that splits light at an energy ratio, as the disclosure is not limited in this respect.

In practical use, when the human eye is in a normal refractive state (e.g., the human eye is a normal human eye or a normal human eye compensated by wearing glasses, contact lenses, etc.), the optical element in the light feeding device (e.g., fig. 5, 6, or 7) does not need to perform focusing operation, and its position is relatively fixed. When the human eye is a near/far vision human eye, the light feeding device of the present disclosure may allow the human eye to see a solid point of view by adjusting one of the sets of elements to achieve clear focus. In principle, the main red light and the fixation light source in the light feeding device can generate a real image surface at the middle image surface position when passing through the projection light path. When the distance between the intermediate image plane and the front focus of the second conjugate mirror is relatively changed, the converging or diverging state of the red light output from the second conjugate mirror is changed. If the human eye is in a near vision state (i.e. a certain diopter exists), the parallel light output by the second conjugate mirror will fall in front of the retina of the human eye. In view of this, the solution of the present disclosure proposes to reduce the distance between the intermediate image plane and the front focal point of the second conjugate mirror so that the red light taken into the human eye from the second conjugate mirror is in a divergent state, so that the red light can be made to fall on the retina of the human eye. Therefore, the refraction compensation of human eyes can be realized by enabling the intermediate image surface where the red light and the fixation point are located to be offset from the front focal point of the second conjugate mirror in the optical axis direction.

Additionally or alternatively, the basic diopter information of the tested human eye can also be converted by the axial difference value (axial distance delta shown in fig. 8) between the front focus of the second conjugate mirror and the intermediate image plane. Here, the adjustment of the axial spacing may include an active feedback adjustment, such as a user actively adjusting the amount of refractive compensation based on the sharpness of the fixation point. In this case, the user can adjust the refractive compensation amount adjustment manually or electrically.

In one embodiment, the foregoing correspondence between the axial distance Δ (mm) between the intermediate image plane and the front focal point of the conjugate mirror 2 and the human eye diopter D is: d=1000Δ/(f2×f2+Δ)), wherein the focal length of the conjugate mirror 2 is f2 (mm). It can be appreciated that Δ is positive when the intermediate image plane is referenced to the front focal point of the conjugate mirror 2 and is far from the conjugate mirror 2.

Further, the aforementioned means for making the accommodation of the refractive power compensation of the human eye may be achieved by a variety of means. To this end, in some embodiments, the light feeding device of the present disclosure may also be provided with one or more drive mechanisms (e.g., stepper motors) that drive the conjugate mirror to move relative to an intermediate image plane formed at the front focal point of the second conjugate mirror, and/or drive the red light source, the projection mirror, and/or the DOE device to move relative to an intermediate image plane formed at the front focal point of the conjugate mirror.

For example, for a nursing device having the configuration shown in fig. 8, the refractive compensation adjustment may be performed with front set focusing. As shown in fig. 8, the driving mechanism can drive the relevant optical devices of the fixation light source and the red light to link, so that the positions of the fixation light source and the intermediate image surface are kept consistent, and the intermediate image surface is offset from the front focus of the conjugate mirror 2, thereby realizing refractive compensation adjustment. Specifically, the red light source, the projection lens, the DOE, the fixation light source and the spectroscope can be linked to realize refraction compensation adjustment.

Further, as shown in FIG. 8, the nursing device may also include a fixation projection lens. The fixation projection lens is operable to project a light beam from a fixation light source at an intermediate image plane location in a lens projection manner. In the refractive compensation adjustment by means of front group focusing, the projection lens and DOE device can also be driven to move with respect to the intermediate image plane formed at the front focal point of the conjugate mirror (conjugate mirror 2) by using the driving mechanism.

For another example, the refractive compensation adjustment may also be performed by means of a back-group focusing. Specifically, the second conjugate mirror may be driven to move by a driving mechanism with respect to an intermediate image plane formed at a front focal point of the second conjugate mirror. As shown in fig. 9, the axial position of the second conjugate mirror may be adjusted by a drive mechanism (moved left and right as shown) to achieve convergence and divergence of the nursing light entering the human eye, thereby compensating for the diopter of the human eye.

Further, in some embodiments, the spots in the present disclosure may have different preset patterns according to different projection requirements, and each preset pattern corresponds to a micro-nano structured diffractive optical element device. As shown in fig. 10, in the use process, a switching mechanism (such as a slot mechanism for supporting the detachable mounting of the DOE devices) may be provided in the light feeding device, and one of the DOE devices having a corresponding micro-nano structure may be switched into the projection light path according to the transmission requirement based on the switching mechanism. By such a switching mechanism, the present disclosure may provide a selectable spot pattern to the user, thereby making the red light nursing effect more personalized.

In some implementations, the annular spot of the present disclosure may have a preset pattern as shown in fig. 11. For example, the annular light spot may include an annular light spot having a gradual visual effect of gradually becoming lighter from the periphery to the center, an annular light spot whose peripheral ring is filled with red light, an annular light spot whose peripheral ring is surrounded by a plurality of circles, an annular light spot whose peripheral ring is arranged in a ring shape of a plurality of lines, an annular light spot whose peripheral ring is composed of a mesh, an annular light spot whose peripheral ring is composed of a lattice, and the like. It should be noted that fig. 11 is only an exemplary illustration of a portion of the preset image, and the preset image that may be provided by the annular light spot in the present disclosure is not limited thereto. For example, in some application scenarios, the annular spot of the present disclosure may also have a deformed, rotated, or combined pattern form of the pattern shown in fig. 11.

In summary, aspects of the present disclosure may enable red illumination of a predetermined region of the fundus. When the light spot is an annular light spot, the nursing scheme of the present disclosure may reduce or equalize the red illuminance of the fovea, thereby avoiding causing intense visual stimulus. At the same time, the red light energy distribution in the peripheral macular region can also be increased. In addition, a fixation point is generated by introducing a fixation light source to assist a user to align with the center of the annular region and provide a visual target for reading refractive information of human eyes. In addition, the basic refractive information of human eyes can be obtained in an active feedback mode of a user. It is emphasized that the description of the projected light path of the present disclosure is merely exemplary and not limiting, and that modifications of the light path to accommodate different application scenarios may also be made by those skilled in the art in light of the teachings of the present disclosure, while still falling within the scope of the present disclosure.

While various embodiments of the present disclosure have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous modifications, changes, and substitutions will occur to those skilled in the art without departing from the spirit and scope of the present disclosure. It should be understood that various alternatives to the embodiments of the disclosure described herein may be employed in practicing the disclosure. The appended claims are intended to define the scope of the disclosure and are therefore to cover all equivalents or alternatives falling within the scope of these claims.

Claims

1. A nursing device, comprising:

a red light source operative to generate red light for illuminating a fundus of a user; and

a projection light path comprising a front set of elements and a rear set of elements and operative to receive the red light and project the red light toward the fundus of the user,

wherein the front group of elements comprises a diffractive optical element device and a projection mirror arranged at an entrance end of the diffractive optical element device, the rear group of elements comprises a conjugate mirror arranged at an exit end of the diffractive optical element device,

wherein the diffractive optical element device is operative to deflect the red light in a direction such that the projection optical path projects a spot at a predetermined region of the user's fundus.

2. The light feeding device of claim 1, wherein the predetermined area of the user's fundus comprises a predetermined area of the macular area, wherein the predetermined area is divided according to the angle of the macular area.

3. The light feeding device of claim 1, wherein the light spot projected at the predetermined area of the user's fundus comprises a circular light spot or an annular light spot.

4. The light feeding device of claim 1, wherein the positions of said projection mirror and conjugate mirror in said projection light path are arranged such that the position of said diffractive optical element device that deflects red light in said direction forms an optical conjugate with the user's pupil position.

5. The light feeding apparatus of claim 2, wherein said conjugate mirror is disposed between said exit end of said diffractive optical element device and the fundus of the user so that the location at which said diffractive optical element device deflects the red light in said direction forms an optical conjugate with the pupil location of the user.

6. The light feeding device of claim 3, wherein the back focal point of said conjugate mirror is located at the pupil of the user and said projection mirror is operative to focus the red light from said red light source onto the projection mirror to focus at the front focal plane of said conjugate mirror.

7. The light feeding device of any one of claims 1-4, wherein said projection light path further comprises said fixation light source operative to illuminate said projection light path for directing said user to look at a spot center.

8. The light feeding device of claim 5, wherein an intermediate image plane is formed at a front focal point of said conjugate mirror, and said projected light path comprises:

a beam splitter disposed between the diffractive optical element device and the intermediate image plane, or between the intermediate image plane and the conjugate mirror, for receiving a light beam from a fixation light source to achieve optical conjugation of the fixation light source with a pupil position of a user.

9. The light feeding device of any one of claims 1-4, wherein a fixation point is formed in said projected light path for directing the user's gaze at the center of said spot.

10. The light feeding device of claim 7, wherein the microstructure of said diffractive optical element device is configured to retain a predetermined proportion of the 0 th order diffracted light at the original angle of incidence to produce said fixation point.

11. The light feeding device of claim 1, wherein said light spots have different preset patterns according to different projection requirements, and each of said preset patterns corresponds to a micro-nano structured diffractive optical element device.

12. The light feeding device of claim 9, further comprising:

and the switching mechanism is operated to switch one of the diffraction optical element devices with the corresponding micro-nano structure into the projection light path according to different projection requirements.

13. The light feeding device of claim 7, further comprising a drive mechanism operative to perform at least one of the following drive to effect refractive compensation of a user's human eye by focusing:

driving the conjugate mirror to move relative to an intermediate image plane formed at a front focal point of the conjugate mirror; and

the red light source, the projection mirror and/or the diffractive optical element device are driven to move relative to an intermediate image plane formed at the front focal point of the conjugate mirror.

14. The light feeding device of claim 11, further comprising a fixation projection mirror operative to project a light beam from said fixation light source in a lens projected manner at said intermediate image plane location, said drive mechanism operative to drive movement of said projection mirror and said diffractive optical element device relative to an intermediate image plane formed at a front focal point of said conjugate mirror.