WO2020091097A1

WO2020091097A1 - Lighting device for dental treatment

Info

Publication number: WO2020091097A1
Application number: PCT/KR2018/013033
Authority: WO
Inventors: 전시욱; 김기현; 김완호; 김재필; 송상빈; 노정현
Original assignee: 덴탈에이스 주식회사
Priority date: 2018-10-30
Filing date: 2018-10-30
Publication date: 2020-05-07

Abstract

A lighting device for dental treatment comprises: multiple LED chips; a light guide having multiple branches corresponding to the LED chips, respectively; an optical coating layer formed on the light guide; a fluorescent film layer formed on the optical coating layer; and a lens part formed above the fluorescent film layer, wherein light exiting each of the multiple LED chips is incident to each of the multiple branches of the optical guide, is propagated by total internal reflection through the optical guide, is emitted through the fluorescent film layer, and then is emitted to the outside through the lens part. Each of the multiple branches of the optical guide has a lens shape at the bottom thereof, and the lens shape at the bottom of the branch may be recessed inside the optical guide.

Description

Dental medical lighting

The present invention relates to a lighting device for dental treatment.

BACKGROUND ART A dental lighting device for illuminating a patient's mouth during dental treatment is known. It is preferable to accurately illuminate the interior of the oral cavity of a patient in need of treatment, and the light emitted from such a lighting device is not preferably projected to other areas (eg, a patient's eye area).

In order to prevent the irradiation light from shining into an area other than the oral cavity, it is common that the shape of the irradiation light from the dental medical lighting device is not circular, but rather oval or square. By doing this, light to the patient's eyes can be minimized.

The conversion of the irradiation form into an ellipse or square shape to suit the patient's oral structure is referred to as 'forming a cut-off line'. In order to form the cut-off line, the light path from the LED light source is controlled. Therefore, a secondary optical system is required to send it to a desired point.

To implement this, the most commonly used method is a method of using an LED light source and a reflector, which has the advantage of high light efficiency and no chromatic aberration because it uses a reflective optical system.

However, the structure is large and it is difficult to form a clear cut-off line, so there is a disadvantage in that light spreads around the line. When multiple light sources are arranged to realize various color temperatures, the distance and the position between the light source and the reflector are all different, so that it is a single reflector. It is difficult to keep the shape for each light source constant.

It is also conceivable to arrange multiple light sources to realize various color temperatures, but when placing multiple light sources, the distance and position between the light source and the reflector are all different, so that the shape of each light source is uniform with one reflector. It is difficult to maintain.

In order to overcome these disadvantages, a method of implementing an accurate cutoff line by inserting a light guide between the light source and the lens has been proposed (Patent Document 1). In this case, it is possible to form a cutoff line neatly by installing a rectangular light guide at the output of the light source, and focusing the light output in the form of a rectangle at the output using a lens. The color deviation can be reduced through color mixing through a guide.

6, the rectangular light guide 300 is installed at the output of the light source 100, and the light output in the rectangular shape from the output is focused using the lens 200. It is possible to form a cut-off line neatly, and it is possible to reduce color deviation occurring in the light source 100 to color mixing through the light guide 300.

On the other hand, in order to increase the output of the LED light source, the size of the light source must be increased. In this case, since the size of the light source is increased, the ability to control the path of light with a lens is reduced. Therefore, as the optical system (lens or reflector) increases, the size of the entire module and product increases.

In addition, although the number of LED light sources is also increased to increase the output of the LED light source, in this case, since there are several light sources, the “light source is further away from the central axis of the lens” and the “light path control is not controlled,” thereby increasing the “light incident”. Since most optical systems have a structure in which a light source is placed at the center of the optical system and the light source and the optical system are matched one-to-one, there is a difficulty in securing illumination illuminance, so the number of modules increases and eventually the size of the lighting product increases. There is also.

In addition, in general, when the LED, the light guide, the barrel, and the optical lens are configured as a single module, when a plurality of modules are used in combination, the number of parts increases and it is also difficult to collect light in one place.

[Patent Document 1] Republic of Korea Patent Publication No. 10-2012-0119482

The present invention is designed to solve the problems of the prior art, the object of the present invention, a dental treatment having a structure for collecting light from a plurality of light sources into one in order to obtain a high light amount in one module (light source + optical system) It is to provide a lighting device.

Another object of the present invention is to provide a compact dental lighting device for easy optical design.

In order to achieve this object, the present invention, as a dental lighting device, a plurality of LED chips, and a light guide having a plurality of branches respectively corresponding to the plurality of LED chips, and an optical coating layer formed on the light guide And a phosphor film layer formed on the optical coating layer, and a lens portion formed on the phosphor film layer, and after light emitted from each of the plurality of LED chips enters each of the plurality of branches, the It provides a lighting device for dental treatment, characterized in that it is taken out through the phosphor film layer, and then taken out through the lens unit by totally reflecting the inside of the light guide.

In this case, lower portions of the plurality of branches may be formed in a lens shape.

Further, each of the plurality of LED chips is composed of a plurality of branched LED chips for each branch of the corresponding light guide, and each of the plurality of branched LED chips is for each branch of the corresponding light guide, Each branch LED chip may be disposed to be substantially parallel to a line segment connecting a start point of curvature and an end point of curvature at the bottom of the branch.

In addition, the lens shape has a depression recessed toward the inside of the light guide, and each of the plurality of LED chips may be arranged to be surrounded by respective corresponding depressions of the plurality of branches.

In addition, the lens unit may be formed of an aspherical lens in which both an emission surface and an incident surface of light.

In addition, it is preferable that the surface roughness of the light guide is 0.4 μm or less.

According to the present invention, it is possible to provide a dental treatment lighting device having a structure for collecting light from a plurality of light sources into one in order to obtain a high light amount from one module (light source + optical system).

In addition, according to the present invention, it is possible to provide a compact lighting device for dental treatment, which is compact and easy in optical design.

1 is a perspective view of a dental treatment lighting device 1 according to a first embodiment of the present invention.

2 is a front view of the dental treatment lighting apparatus 1 according to the first embodiment of the present invention.

3 is a plan view of a lighting device 1 for dental treatment according to a first embodiment of the present invention.

4 is a front view showing an arrangement relationship between the LED chips 10-1, 10-2, and 10-3 and the light guide 20 different from FIG. 1.

5 is a front view of a lighting device for dental treatment according to a second embodiment of the present invention.

6 is a schematic view of a lighting device for dental treatment according to the prior art.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

1 shows a dental treatment lighting device 1 according to a first embodiment of the present invention. 2 is a front view of the dental treatment lighting device 1 according to the first embodiment of the present invention. 3 is a plan view of the dental treatment lighting device 1 according to the first embodiment of the present invention.

The dental treatment lighting device 1 includes a plurality of LED chips 10-1, 10-2, and 10-3, a light guide 20, an optical coating layer 30, a phosphor film layer 40, and a lens unit ( 50).

The plurality of LED chips are light sources, and in the embodiment of the present invention, three LED chips 10-1, 10-2, and 10-3 are provided. However, the number of LED chips is not limited. The LED chips 10-1, 10-2, and 10-3 are mounted to be electrically connected to a substrate (not shown) to emit light, and the method mounted on the substrate is not particularly limited, but flip chip (Flip chip) is preferably mounted in a manner.

Recently, in order to improve the lighting quality and density of LED products, the unit area luminous efficiency (lm / W / cm ² ) has become an important indicator for measuring LED chips. Compared to traditional GaN-based LED structures, flip chips are It is known to have excellent heat dissipation ability and current spreading ability. Therefore, a high-pressure flip product formed in series by using a flip LED chip as an LED chip is more advantageous in securing a high unit area luminous efficiency and significantly reducing driver cost.

In addition, since the flip chip method is a self-evident technique in the related field, a more detailed description is omitted, and this is a structure without an electrode pad on the upper surface, and thus it is possible to secure color uniformity of illuminance.

The shape of the LED chip (10-1, 10-2, 10-3) is preferably rectangular, but a square may be applied, and the wavelength range may be any of blue to ultraviolet light (UV: Ultraviolet Ray) wavelength range. It is desirable to have one wavelength region.

On the other hand, each of the LED chips 10-1, 10-2, and 10-3 may be composed of a single LED chip, or may be composed of a plurality of branched LED chips. This will be described with reference to FIG. 4.

4, each of the three LED chips 10-1, 10-2, and 10-3 is a single LED with respect to the branches 20-1, 20-2, and 20-3 of the corresponding light guide 20. In the case of having a plurality of branched LED chips rather than chips, a specific arrangement relationship between the light guide and the LED chips is shown.

The three branches 20-1, 20-2, 20-3 of the light guide 20 have the same arrangement relationship as the respective three LED chips 10-1, 10-2, 10-3. Therefore, only one branch 20-2 will be described.

Since the lower end of the branch 20-2 is processed into a lens shape, the corresponding lens shape has a starting point (R1) and an ending point (R1 ') of curvature, and the center of curvature (R0) is located at the center of the lens. At this time, the plurality of branch LED chips 10-2A and 10-2B are disposed symmetrically to each other about the central axis CX of the branch 20-2, wherein the branch LED chips 10-2A are curvatures. A line connecting the start point R1 and the end point R1 'of curvature is arranged such that the light emitting surfaces are approximately parallel, and the branch LED chips 10-2B are similarly arranged.

Here, the term 'approximately parallel' means that the light emitted from the light emitting surface of the branch LED chip does not mean the parallel which is completely coincident with each other, but the branches 20-1, 20-2, and 20-3 of the light guide 20. It should be understood as meaning that the branch LED chips are disposed along the curvature of the lens shape formed at the bottom of the branch so as to be able to substantially advance through total reflection.

In this arrangement, when light emitted from each of the branch LED chips 10-2A and 10-2B passes through the lower end of the lens shape of the branch 20-2, condensing is performed more efficiently than other arrangements. The same effect is obtained for the other two LED chips 10-1, 10-3 and the other two branches 20-1, 20-3.

The light guide 20 has three branches 20-1, 20-2, 20-3 in this embodiment, and each branch is a corresponding LED chip 10-1, 10-2, 10-3 ) To receive light. The light guide 20 is preferably made of a glass material as a whole. In particular, soda lime glass having a high light transmittance may be used as a material for the light guide 20. However, the material of the light guide 20 is not limited to a glass material, and may be a transparent plastic (lens injection mold) such as PMMA (Polymethyl Methacrylate) or polycarbonate (PC).

The lower end of each branch of the light guide 20 is preferably processed into a lens form (lance injection mold) to efficiently receive light from the LED chips 10-1, 10-2, 10-3.

The light guide 20 is configured to receive light from the LED chips 10-1, 10-2, and 10-3 to totally reflect the inside. As described above, the light guide 20 must guide the light by using the total reflection principle to collect the light, so the surface roughness must be very low. This is because the higher the surface roughness, the greater the degree of roughness, and the light escapes without total reflection.

In this embodiment, it is preferable that the surface roughness of the light guide 20 is 0.4 μm or less. When the surface roughness exceeds 0.4 µm, the total reflection condition is not established and light is leaked to the outside, which is not preferable.

The optical coating layer 30 is laminated on the top surface of the light guide 20 using an adhesive or the like, and a phosphor film layer 40 is deposited thereon. In this embodiment, a transparent silicone adhesive 60 was used.

The optical coating layer 30 may be made of a general optical coating material. However, the optical characteristic of the optical coating layer 30 is a dichroic filter that transmits the blue-UV region (300-480 nm) and reflects the green-red region (480-750 nm) to increase light efficiency. Can order

The phosphor film layer 40 is a film that converts the wavelength of light emitted from the LED chip, and allows light having the converted wavelength to form an arbitrary cut-off line according to a pre-designed form and exit, preferably silicon , Epoxy, plastic, glass (glass) is any one of the transparent resin material and a certain amount of phosphor mixed film.

In addition, the type and number of phosphors included in the phosphor film layer 40 may vary according to a desired color temperature and color rendering index.

For example, the phosphors included in the phosphor film layer 40 according to the present embodiment include ceramic-based phosphors, quantum dot phosphors, garnet-based phosphors, silicate-based phosphors, and nitride-based phosphors, It may be selected from oxynitride-based phosphor.

On the other hand, when the LED chips (10-1, 10-2, 10-3) are constructed of high power, glass phosphors mixed with phosphors using glass frit to increase heat resistance, ceramics Phosphor ceramic, single crystal phosphor, and polycrystalline phosphor may be used as the phosphor.

The phosphor film layer 40 may be configured to have various color temperatures from 2000k to 7000k depending on the treatment purpose.

The lens unit 50 is the light emitted from the LED chip (10-1, 10-2, 10-3) passes through the phosphor film layer 40 to the patient's desired lesions (eg, oral, etc.) To be investigated. Therefore, light emitted from the lens unit 50 is projected to the patient's mouth.

It is preferable that the lens unit 50 is a lens in which both the incident surface and the exit surface are formed aspherical surfaces. The curvature of the curved surfaces on both sides of the lens may be formed in various ways according to the irradiation form desired by the user.

The lens unit 50 is composed of a single lens having both aspherical surfaces, but may be formed of a predetermined optical system in which a plurality of lenses are arranged to obtain a desired irradiation form. Further, the lens unit 50 may have a predetermined magnification by a plurality of lenses. Therefore, the lens unit 50 can adjust the irradiation width of the light beam according to the size of the affected area where light irradiation is required.

Hereinafter, the operation of the dental treatment lighting apparatus 1 according to the embodiment of the present invention configured as described above will be described.

Light emitted from the three LED chips (10-1, 10-2, 10-3) enters through the branches (20-1, 20-2, 20-3) of the light guide 20, the light guide ( 20) Total internal reflection. The light thus advanced is taken out through the lens unit 50 through the optical coating layer 30 and the phosphor film layer 40.

According to such a dental lighting device (1), it is possible to collect light from several LEDs to a single point, the brighter the light from a small area, the more compact the light can be, and the easier the optical design is. Has an advantage. In particular, the present invention may have strengths when constructing small but bright lighting.

In addition, in general, the LED + light guide + lens tube + optical lens is composed of a single module and then used in combination of multiple modules. The present invention reduces the number of components and makes it easier to collect light in one place.

5 discloses a front view of a lighting device for dental treatment according to a second embodiment of the present invention.

In the second embodiment, the lens shape formed at the bottom of the branches 20-1 ', 20-2', and 20-3 'of the light guide 20' is a shape recessed toward the inside of the light guide 20 '. It differs from the first embodiment in that the LED chips 10-1 ', 10-2', and 10-3 'are arranged around the recessed portion. The rest of the components and features are the same as in the first embodiment.

According to the dental treatment lighting apparatus according to the second embodiment, the lower end of the branch 20-1 ', 20-2', 20-3 'of the light guide 20' is formed in a lens shape, but the first implementation Unlike the example, it has recesses 22-1, 22-2, 22-3 recessed inside the light guide 20 '. In addition, the LED chips 10-1 ', 10-2', and 10-3 'are arranged to be surrounded by corresponding recesses 22-1, 22-2, and 22-3, respectively. This arrangement is such that the LED chip is glued using an adhesive or the like to inscribe the recess, or the LED chip (10-1 ', 10-2', 10-3 ') and light guide (20') are attached to the base or frame (not shown). In mounting), it can be achieved by placing the LED chip so as to be surrounded by the depression of each corresponding branch of the light guide.

According to such a dental lighting device, like the device of the first embodiment, light from several LEDs can be collected to one point, and the brighter the light from a small area, the more compact the lighting can be, It has the advantage of facilitating optical design. In particular, the present invention may have strengths when constructing small but bright lighting.

Particularly, according to the second embodiment, the light efficiency is better because the light guide 20 'can pass more light inside (so-called' funnel effect ') compared to the first embodiment. have.

As described above, although described with reference to preferred embodiments of the present invention, those skilled in the art will variously modify and change the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. You can understand that you can.

In addition, in the process of explaining an embodiment of the present invention, the thickness of the lines or the size of components shown in the drawings may be exaggerated for clarity and convenience of description, and the above-mentioned terms consider functions in the present invention. As the terms are defined as it may vary according to the user's or operator's intention or practice, the definition of these terms should be made based on the contents throughout the specification.

Claims

As a dental lighting device,

A plurality of LED chips,

An optical guide having a plurality of branches corresponding to the plurality of LED chips,

An optical coating layer formed on the light guide,

A phosphor film layer formed on the optical coating layer,

It includes a lens portion formed on the phosphor film layer,

After the light emitted from each of the plurality of LED chips is incident on each of the plurality of branches, the light guide is totally reflected inside and then taken out through the phosphor film layer and then taken out through the lens unit. Characterized in that, a dental lighting device.
The method according to claim 1,

The lower portion of the plurality of branches is characterized in that formed in the form of a lens, dental lighting device.
The method according to claim 2,

Each of the plurality of LED chips is composed of a plurality of branch LED chips for each branch of the corresponding light guide, and each of the plurality of branch LED chips is branched with respect to each branch of the corresponding light guide. Characterized in that, each of the branch LED chips are arranged substantially parallel to the line segment connecting the start point of the curvature and the end point of the curvature at the bottom.
The method according to claim 2,

The lens form has a depression that is recessed toward the inside of the light guide, wherein each of the plurality of LED chips is arranged to be surrounded by each corresponding depression of the plurality of branches, dental treatment lighting Device.
The method according to claim 1,

The lens unit is characterized in that the light emitting surface and the incident surface are both formed of an aspherical lens, dental illumination device.
The method according to any one of claims 1 to 5,

The surface roughness of the light guide is characterized in that less than 0.4㎛, dental lighting device.