Optical structure for oral scanning mirror and oral scanning mirror

Abstract

The present invention discloses an optical structure for an oral scanning mirror and an oral scanning mirror, comprising an optical structure, characterized in that the optical structure comprises a biconvex lens A, an aperture, a negative meniscus lens, a plano-concave lens and a biconvex lens B arranged in sequence from left to right along the incident direction of light. The present invention simplifies the optical structure and the light transmission path by arranging the biconvex lens A, the aperture, the negative meniscus lens, the plano-concave lens and the biconvex lens B in sequence from left to right, which not only effectively reduces the interference of external factors, but also effectively reduces distortion, so that the image transmitted by the lens equipped with the optical structure is more realistic, which is convenient for the prevention and later treatment of oral diseases.

Description

Technical Field

[0001] The invention belongs to the technical field of oral scanning, and in particular relates to an optical structure used for an oral scanning mirror and an oral scanning mirror. Background Art

[0002] Oral health is an important part of overall health. In 2007, the World Health Organization proposed that oral diseases are a serious public health problem that requires active prevention and treatment. Oral diseases such as caries and periodontal disease can damage the hard tissues of teeth and the supporting tissues around them. In addition to affecting functions such as chewing, speech, and aesthetics, they can also cause social interaction difficulties and psychological disorders. Some microorganisms exist in the oral cavity for a long time, which can cause or aggravate certain systemic diseases such as coronary heart disease and diabetes, endangering overall health and affecting the quality of life. Oral examinations are particularly important for the prevention and treatment of oral diseases. Traditional oral examinations are conducted through human eyes. Naked eye observation is easily affected by the surrounding light intensity and the detection angle, which is extremely inconvenient, and the detection efficiency and effect are poor, so oral diseases cannot be prevented and treated in time, thus affecting the health of the body.

[0003] At present, oral examinations generally use oral mirrors for scanning. Although it can improve the detection efficiency and is conducive to the timely prevention and treatment of oral diseases, the lenses of oral mirrors mostly use one or more classified combinations of lenses, reflectors, etc. to transmit light. Since the distribution relationship and arrangement order of these combinations change, the light transmission will change accordingly, so the image transmitted by the light will also be different, and the imaging effect will also be different. For example, Chinese patent document announcement number CN113080877A, publication date: July 9, 2021, discloses a device and method for oral scanning using a light field camera. The article proposes "including a collection end and a holding body, the collection end is detachably connected to the holding body, one end of the holding body is provided with a light receiving window, and a reflector is provided in the collection end The mirror transfers the collected image of the inside of the oral cavity to the light receiving window; the inside of the holding body is provided with a light compensation component and a light field camera in sequence along the incident direction of the light, the light compensation component includes an illumination light source and a light transmission mechanism, the light transmission mechanism transmits the compensation light of the illumination light source to the reflector, and the light field camera receives the image information acquired by the collection end head. This prior art restores the three-dimensional model of the inside of the oral cavity through digital modeling, and the digital modeling is established according to the image transmitted by the light of the optical structure. Since the light transmission path of the optical structure of this prior art is complex and is easily disturbed by external conditions, the distortion is large and it is impossible to present a more realistic oral image. In addition, the depth of field of the lens is small, so there is a huge error in the digital modeling, which poses a great hidden danger to the later treatment of oral diseases. Therefore, a new technical solution is needed to solve the above technical problems. Summary of the invention

[0004] The purpose of the present invention is to provide an optical structure and an oral scanning mirror for an oral scanning mirror, so as to solve the problems raised in the above background technology that the light transmission path of the oral scanning mirror at the current stage is complex, easily disturbed by external conditions, has large distortion, and has large oral image errors, which affects the prevention and treatment of oral diseases.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solution: an optical structure for an oral scanning mirror, characterized in that the optical structure includes a biconvex lens A, an aperture, a meniscus negative lens, a plano-concave lens and a biconvex lens B arranged in sequence from left to right along the incident direction of light.

[0006] Furthermore, the biconvex lens A is arranged closely to the aperture, and a glass sheet is arranged on the rear side of the biconvex lens B, and the rear side of the glass sheet is the image plane, so that the image plane obtains an actual image of the image plane during the light transmission of the optical structure.

[0007] Furthermore, the air gap between the biconvex lens A and the meniscus negative lens is 1.10-1.14 mm, the air gap between the meniscus negative lens and the plano-concave lens is 4.75-4.79 mm, and the air gap between the plano-concave lens and the biconvex lens B is 4.56-4.60 mm, which increases the depth of field of the lens and reduces distortion.

[0008] Furthermore, the mirror apertures of the biconvex lens A, the negative meniscus lens and the plano-concave lens are equal, and the mirror aperture of the biconvex lens B is larger than the biconvex lens A, the negative meniscus lens and the plano-concave lens with the same mirror apertures, so that the image surface can present a more realistic image on the biconvex lens B with a large mirror aperture.

[0009] In addition to the above technical solutions, there is also an oral scanning mirror including the optical structure.

[0010] Compared with the prior art, the present invention has the following beneficial effects:

[0011] 1. The optical structure of the present invention and the oral scanning mirror including the optical structure utilize a biconvex lens A, an aperture, a negative meniscus lens, a plano-concave lens and a biconvex lens B arranged in sequence from left to right in the direction of incident light, thereby streamlining the optical structure and also simplifying the path of light transmission, which not only effectively reduces the interference of external factors, but also effectively reduces distortion, making the image transmitted by the lens equipped with the optical structure more realistic, and facilitating the prevention and later treatment of oral diseases.

[0012] 2. The present invention uses air to space the biconvex lens A, the meniscus negative lens, the plano-concave lens and the biconvex lens B at corresponding distances, so that the depth of field of the lens is effectively increased, thereby making the image formed by the lens equipped with the optical structure clearer and more realistic.

[0013] 3. The present invention adopts a biconvex lens B whose mirror diameter is larger than that of a biconvex lens A with the same mirror diameter, a meniscus negative lens and a plano-concave lens, so that the image surface can be fully projected onto the biconvex lens B under the large-diameter mirror of the biconvex lens B, so that the image presented is of actual size, reducing the error of image transmission and ensuring the authenticity of the oral image. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the optical structure of the present invention;

[0015] Figure 2 It is an MTF curve diagram of the imaging quality of the lens of the present invention.

[0016] Among them: 1. Biconvex lens A; 2. Aperture; 3. Meniscus negative lens; 4. Plano-concave lens; 5. Biconvex lens B; 6. Glass sheet; 7. Image plane. DETAILED DESCRIPTION

[0017] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0018] Embodiment 1:

[0019] like Figure 1 As shown, an optical structure for an oral scanning mirror includes an optical structure, wherein the optical structure includes a biconvex lens A1, an aperture 2, a meniscus negative lens 3, a plano-concave lens 4 and a biconvex lens B5 arranged in sequence from left to right along the incident direction of light;

[0020] The biconvex lens A1 is closely arranged with the aperture 2, the air interval between the biconvex lens A1 and the negative meniscus lens 3 is 1.10-1.14mm, the air interval between the negative meniscus lens 3 and the plano-concave lens 4 is 4.75-4.79mm, the air interval between the plano-concave lens 4 and the biconvex lens B5 is 4.56-4.60mm, a glass sheet 6 is arranged at the rear side of the biconvex lens B5, and the rear side of the glass sheet 6 is an image plane 7, which simplifies the optical structure and the light transmission process, effectively reduces the interference of external factors, and effectively reduces the distortion, so that the image transmitted by the lens equipped with the optical structure is more realistic, which is convenient for the prevention and later treatment of oral diseases;

[0021] The mirror diameters of the biconvex lens A1, the negative meniscus lens 3 and the plano-concave lens 4 are equal, and the mirror diameter of the biconvex lens B5 is larger than the biconvex lens A1, the negative meniscus lens 3 and the plano-concave lens 4 with the same mirror diameters, so that the image plane 7 can be fully projected onto the biconvex lens B5 under the large-diameter mirror of the biconvex lens B5, so that the image presented is of actual size, reducing the error of image transmission and ensuring the authenticity of the oral image;

[0022] The optical structure of the oral scanning mirror is composed of high-refractive-index and low-dispersion flint glass and high-refractive-index and high-dispersion crown glass to eliminate chromatic aberration and dispersion. The glass combination with a larger refractive index can correct the field curvature, so that the lens equipped with this optical structure ensures an approximate proportional distribution of refractive index and optical power, and ensures the balance of the incident angles of the front and rear lenses, so as to reduce the sensitivity of the lens and improve the possibility of production.

[0023] The specific plan is as follows:

[0024]

[0025] According to the technical parameters of the above lens, the technical indicators that can be achieved by this lens are as follows:

[0026] Focal length: 21.99mm

[0027] Working F / #: 8.5*6.5

[0028] Image field 2η': ≥φ4.07mm

[0029] Distortion: <0.1%

[0030] Total optical path length∑≤120mm, optical back intercept L'≤5mm

[0031] Applicable spectral range: 450~620nm.

[0032] from Figure 2 It can be seen that when imaging with visible light, at a low frequency of 10lp / mm, the MTF is greater than 90%, and the lens equipped with this optical structure has a higher resolution. At 60lp / mm, the MTF is greater than 50%, and the lens equipped with this optical structure has good contrast characteristics, so that the depth of field of the lens equipped with this optical structure reaches ±6mm, which meets the actual requirements of oral examination and ensures the authenticity of the examination results.

[0033] The advantages of a lens equipped with this optical structure are:

[0034] (1) The lens equipped with this optical structure uses only four glass lenses for light transmission, with small distortion and simple structure;

[0035] (2) The lens equipped with this optical structure is composed of flint glass with high refractive index and low dispersion and crown glass with high refractive index and high dispersion to eliminate chromatic aberration and dispersion;

[0036] (3) The depth of field of the lens equipped with this optical structure reaches ±6mm;

[0037] (4) The lens equipped with this optical structure has good contrast characteristics;

[0038] (5) The images transmitted by the lens equipped with this optical structure are more realistic, which is convenient for the prevention and subsequent treatment of oral diseases.

[0039] Embodiment 2:

[0040] As another object of the present invention, an oral scanning mirror is provided. The oral scanning mirror, especially the optical structure in Example 1, is provided with any of the above optical structures. Therefore, the oral scanning mirror can obtain any beneficial effect of the optical structure described above, which will not be repeated here.

Claims

1. An optical structure for an oral scanning mirror, characterized in that: The optical structure includes a biconvex lens A, an aperture, a meniscus negative lens, a plano-concave lens and a biconvex lens B which are arranged in sequence from left to right along the incident direction of light. The biconvex lens A is arranged closely to the aperture, a glass sheet is arranged on the rear side of the biconvex lens B, an air gap between the biconvex lens A and the meniscus negative lens is 1.10-1.14 mm, an air gap between the meniscus negative lens and the plano-concave lens is 4.75-4.79 mm, an air gap between the plano-concave lens and the biconvex lens B is 4.56-4.60 mm, the mirror apertures of the biconvex lens A, the meniscus negative lens and the plano-concave lens are equal, and the mirror aperture of the biconvex lens B is greater than that of the biconvex lens A, the meniscus negative lens and the plano-concave lens with equal mirror apertures.

2. An oral scanning mirror, comprising the optical structure for an oral scanning mirror according to any one of claims 1.

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