This standard specifies the basic requirements for various trial lenses used to test refractive defects of the human eye. This standard applies to all types of full-aperture and reduced-aperture trial lenses. GB 17342-1998 Ophthalmic instrument trial lenses GB17342-1998 standard download decompression password: www.bzxz.net
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GB17342--1998 This standard adopts the contents of IS09801:1997 "Ophthalmic Instruments--Trial Case Lenses" in a non-equivalent manner. This standard is proposed by the National Institute of Metrology and is under the jurisdiction of the National Institute of Metrology. This standard is drafted by the National Institute of Metrology. The main drafters of this standard are: Wang Liru, Ma Zhenya, and Liu Wenli. This standard was first issued in May 1998 Standard Soumai Network Line Section 1 Scope National Standard of the People's Republic of China Ophthalmic Instrument--Trial Case Lenses Ophthalmic instrument--Trial case lenses This standard specifies the basic requirements for various trial case lenses used to test refractive defects of the human eye. This standard applies to all kinds of full aperture and reduced aperture trial lenses 2 Reference standards GB 17342--1998 neq IS 9801:1997 The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard is published, the versions shown are valid. All standards will be revised, and parties using this standard should explore the possibility of using the latest versions of the following standards. GB10050-88 Reference wavelength for optics and optical instruments GB2828-89 Sampling procedures and sampling tables for batch inspection by counting (applicable to inspection of continuous batches) GB/T1546.4-~1995 General technical conditions for instrument packaging JJG579--98 Trial lens box JG580-96 Focimeter 3 Definitions This standard adopts the following definitions. 3.1 Trial case lenses Lenses that are set in a frame and used to measure the light defects of the human eye. 3.2 Full-aperture trial case lenses Lenses with a protective frame and a maximum limit aperture. 3.3 Reduced-aperture trial case lenses Lenses with a light aperture that is significantly smaller than the outer diameter of the frame and a significantly thinner thickness. 3.4 Additive power trial case lenses A chain of spherical lenses, cylindrical lenses or spherical-cylindrical combined trial lenses. The back power measured on the last side is equal to the sum of the nominal values of all trial lenses placed in the frame on the meridian. 3.5 Vertex power The reciprocal of the paraxial focal length of the lens measured in meters. Each lens has two vertex powers. 3.6 Back-vertex power The reciprocal of the paraxial back-vertex focal length of the lens measured in meters. As shown in Figure 1, the distance from the back vertex of the lens to the back focus of the lens is called the back vertex focal length, and the reciprocal of the back vertex focal length is called the back focal power, that is, 1/1. - In general, the vertex power of a lens refers to its back vertex power. The unit of vertex power is the reciprocal of the meter (m\1), and the unit name is diopter, represented by the symbol D. Approved by the State Administration of Quality and Technical Supervision on May 5, 1998 and implemented on December 1, 1998 GB17342-1998 Figure 1 Schematic diagram of back vertex focal length The vertex power of trial lenses is related to the wavelength. This standard stipulates that the wavelength used is the green mercury line, λ-546.07nm. The back vertex power of a cylindrical lens refers to the vertex power of the main meridian plane whose diopter is not zero. Note: The vertex power of the other main meridian plane of the cylindrical lens is zero. 3.7 Prismatic power The deviation of light passing through a certain point on the lens (see Figure 2). The unit of prismatic power is centimeters per meter (cm/m), and the unit name is prismatic diopter, which is represented by the symbol "△". Figure 2 Prismatic power 4 Requirements 4.1 General Prescription lenses shall comply with the requirements of Articles 4.2, 4.3 and 4.4 and be inspected in accordance with the requirements of Chapter 5. 4.2 Optical requirements 4.2.1 Tolerance of the vertex power of spherical lenses 4.2.1.1 The vertex power of plano lenses shall comply with the requirements of Table 1. Table 1 Tolerance of the vertex power of plano lenses Nominal value of vertex power Spherical power 4.2.1.2 The vertex power tolerance of spherical lenses shall comply with the requirements of Table 2. Cylinder power Table 2 Tolerance of vertex power of spherical lens Nominal value of vertex power (absolute value) >0.12~6.00 >6.00 ~12.00 Youmai.com Spherical power Prismatic power Cylinder power 4.2.2 Tolerance of cylinder power of cylindrical lens GB17342—1998 The tolerance of cylinder power of cylindrical lens shall comply with the requirements of Table 3, and its spherical power tolerance shall not exceed ±0.06D; its prismatic power tolerance shall not exceed 0.12 cm. Table 3 Tolerance of cylindrical power of cylindrical sheet Nominal value of cylindrical power (absolute value) >0.12~1.00 ≥1.00~4.00 >4.006.00 4.2.3 Tolerance of prismatic power of prism sheet The tolerance of prismatic power of prism sheet shall comply with the requirements of Table 4. Table 4 Prism tolerance of prism lenses Prism nominal value >3~6 4.2.4 Optical center tolerance Prism, △ Spherical power, D Cylindrical power, I) The optical center displacement of spherical and cylindrical lenses is expressed by the prism at the geometric center of the lens circle, and the optical center tolerance shall comply with the provisions of Table 5. Table 5 Optical centre tolerance Nominal value of vertex power (absolute value) 0.12~2.00 >2. 00 ~~5. 00 >5. 00~8. 00 >8. 00~12. 00 Prism tolerance 4.2.5 Cylindrical lens axis tolerance The axis line of the cylindrical lens is specified as 0°~~180°. The deviation between it and the axis marks at both ends of the lens diameter is expressed in angle, and its value should comply with the provisions of Table 6. Nominal value of cylindrical power (absolute value) 4.2.6 Tolerance of prism lens base line GB 17342--1998 Table 6 Tolerance of axial position of cylindrical lens The axial position of the prism lens base is represented by the prism base line, and its deviation shall comply with the provisions of Table 7. Table 7 Tolerance of prism base line Nominal value of prism power >0.5~1. 00 >1. 00 ~ 2. 00 >2. 00~10. 00 4.3 Structural requirements This requirement applies to all lens rings and mounted lenses. 4.3.1 Specifications and dimensions Tolerance of axial position The trial lens shall be equipped with a rounded outer frame with a round edge thickness not exceeding 1.4 mm. The outer diameter of the installed lens ring should be 38mm ± 0.2 mm. The overall thickness of the trial lens including its frame shall not exceed 2.8mm. The trial lens should be able to fit into the trial frame with a spacing of 3mm between each lens. The thickness of the full-aperture spherical lens greater than 5D is allowed to exceed 2.8mm, and the thickness of the full-aperture and reduced-aperture prism lens greater than 3A on the side close to the object side is allowed to exceed 2.8mm. 4.3.2 Effective light aperture The effective light aperture of the trial lens with a nominal vertex power less than 12D shall not be less than 18mm; the effective light aperture of the trial lens with a nominal vertex power greater than 12D shall not be less than 16mm. 4.3.3 Structure 4.3.3.1 Prism When installing the prism, the surface close to the eye should be parallel to the mounting surface. The nominal value marked on the frame should be the prism power when the lens is incident vertically close to the eyeball, and should be consistent with the value measured by the focal meter. 4.3.3.2 Frames The outer frame of the trial lens should not have any sharp edges, sharp corners or rough surfaces that could cause harm to the patient or optometrist. 4.4 Materials and surface quality 4.4.1 Materials The materials used for the frame should not contain any corrosive components. 4.4.2 Surface quality The trial lens shall not have bubbles, defects (impurities), scratches or any irregular surface defects observable by naked eyes within the effective aperture. 5 Inspection method 5.1 Inspection of optical quantity GB17342-1998 The tolerance inspection of optical quantity shall be carried out using a focimeter with a reading interval of 0.01D and a temperature of 20C±5℃ and a relative humidity of less than 85%. 5.1.1 Place the trial lens on the support seat of the focimeter for inspection. 5.1.2 When inspecting the vertex power of the lens, the imaging center of the lens shall be aligned with the crosshairs of the reticle, and the prism power indication shall be zero or minimum. 5.1.3 When inspecting the displacement of the optical center of the lens, the geometric center of the lens shall first be located at the geometric center of the lens support seat. In order to reduce the measurement error, the lens needs to be slightly rotated to make the prism power in the vertical direction zero. At this time, the prism power obtained in the horizontal direction is the optical center displacement of the lens under test. 5.1.4 When inspecting the axis mark of the lens, the axis mark at both ends of the lens ring should be coincident with the three-point connection line of the printing mechanism of the focal meter, and the axis deviation of the lens under test can be read. 5.1.5 The method for inspecting the baseline of the prism lens is the same as that in 5.1.4. 5.2 Inspection of material and surface quality The inspection of material and surface quality is carried out by visual inspection using the "bright/dark" interface method. Figure 3 is the inspection system. It is required to inspect the lens under a bright field background of about 2001x, and the illumination light source should use a fluorescent lamp of 15W or more (or an incandescent lamp of 60W or more). The inspection personnel are required to have certain practical experience. 30m 1--dark background without light (150mm×360mm); 2-fluorescent lamp; 3-shade (adjustable baffle); 4-movable trial lens; 5-observation plane: a--adjustable distance of the shading plate Figure 3 Schematic diagram of the surface quality inspection device for trial lenses 5.3 Structural inspection Use a vernier caliper with an accuracy of not less than 0.05mm. The surface quality of the outer frame is visually inspected in accordance with the method in 5.2. 6 Inspection rules 6.1 The factory products shall be inspected as a whole by box according to the requirements specified in this standard. It is required that the single item qualified rate of spherical lenses and cylindrical lenses in each box shall not be less than 90%. The qualified rate of spherical lenses, cylindrical lenses and prismatic lenses in the whole box shall not be less than 85%. 6.2 The batch products shipped from the factory shall be sampled and inspected according to the requirements of special inspection level S-3 and AQL 4.0 of GB2828, see Table 8 for details. Table 8 Product batch range 1~15 51~150 151500 Sampling sample size Number of qualified judgments Number of unqualified judgments GB 17342 1998 6.3 For products with special specifications, an agreement can be reached according to the requirements of both the supply and demand parties. 7 Marking, packaging, transportation and storage 7.1 Marking 7.1.1 The nominal values of the vertex power and prismatic power of the lens shall be marked on the frame. 7.1.2 The axis position or baseline of the cylindrical lens and prismatic lens shall be marked on the frame or lens respectively. If there is no measure to prevent the lens from rotating in the frame, the cylindrical axis position or prismatic baseline shall be marked directly on the lens. 7.1.3 The marking color and the specific frame help to identify the type and category of lenses; while the spherical power, cylindrical power and prismatic power can be read directly from the indication mark. The marking should be marked on the frame on the side opposite to the eyeball. 7.1.4 Each type of lens should be distinguished by frames of different colors and/or markings of different colors in accordance with the provisions of Table 9. Table 9 Lens identification markings Lens category Spherical and cylindrical lenses Prismatic lenses Massachusetts rod lenses Slit lenses Pinhole lenses Frosted lenses Cross lenses Red filters Green filters Polarization filters Note: The axis of the negative cylinder of the cross-cylindrical lens should be marked in red. 7.2 Packaging 7.2.1 Trial lenses should be packed in boxes according to their categories. Letters or symbols Vertex value I or ss O or PH · or BL ① or CL 7.2.2 The box should be accompanied by an instruction manual, which should also include the following contents: a) the name and address of the manufacturer; b) an introduction to the disinfection method of trial lenses; c) an explanation of the method of stacking trial lenses; d) the code of the implementation standard: e) packing list. 7.2.3 Marking of trial lens boxes Trial lens boxes should include the following permanent markings: a) the name and address of the manufacturer; b) the brand and model of the trial lens box; c) the factory number, 7.3 The outer packaging of the trial lens box should comply with the requirements of GB/T15464. 636 Bottom Frame color or identification mark White or black GB17342—1998 7.4 During transportation and handling, the product should be placed and unloaded with care, and collision, rain and moisture are strictly prohibited. 7.5 During storage, the product should be ventilated and dry to prevent moisture.4 All types of lenses shall be distinguished by frames of different colors and/or markings of different colors as specified in Table 9. Table 9 Lens identification markings Lens categories Spherical and cylindrical lenses Prismatic lenses Massachusetts rod lenses Slit lenses Pinhole lenses Frosted lenses Cross lenses Red filters Green filters Polarization filters Note: The axis position of the negative cylinder of the cross-cylindrical lens shall be marked in red. 7.2 Packaging 7.2.1 Trial lenses shall be packed in boxes according to their categories. Letters or symbols Vertex value I or ss O or PH · or BL ① or CL 7.2.2 The box should be accompanied by an instruction manual, which should also include the following contents: a) the name and address of the manufacturer; b) an introduction to the disinfection method of trial lenses; c) an explanation of the method of stacking trial lenses; d) the code of the implementation standard: e) packing list. 7.2.3 Marking of trial lens boxes Trial lens boxes should include the following permanent markings: a) the name and address of the manufacturer; b) the brand and model of the trial lens box;bzxz.net c) the factory number, 7.3 The outer packaging of the trial lens box should comply with the requirements of GB/T15464. 636 Bottom Frame color or identification mark White or black GB17342—1998 7.4 During transportation and handling, the product should be placed and unloaded with care, and collision, rain and moisture are strictly prohibited. 7.5 During storage, the product should be ventilated and dry to prevent moisture.4 All types of lenses shall be distinguished by frames of different colors and/or markings of different colors as specified in Table 9. Table 9 Lens identification markings Lens categories Spherical and cylindrical lenses Prismatic lenses Massachusetts rod lenses Slit lenses Pinhole lenses Frosted lenses Cross lenses Red filters Green filters Polarization filters Note: The axis position of the negative cylinder of the cross-cylindrical lens shall be marked in red. 7.2 Packaging 7.2.1 Trial lenses shall be packed in boxes according to their categories. Letters or symbols Vertex value I or ss O or PH · or BL ① or CL 7.2.2 The box should be accompanied by an instruction manual, which should also include the following contents: a) the name and address of the manufacturer; b) an introduction to the disinfection method of trial lenses; c) an explanation of the method of stacking trial lenses; d) the code of the implementation standard: e) packing list. 7.2.3 Marking of trial lens boxes Trial lens boxes should include the following permanent markings: a) the name and address of the manufacturer; b) the brand and model of the trial lens box; c) the factory number, 7.3 The outer packaging of the trial lens box should comply with the requirements of GB/T15464. 636 Bottom Frame color or identification mark White or black GB17342—1998 7.4 During transportation and handling, the product should be placed and unloaded with care, and collision, rain and moisture are strictly prohibited. 7.5 During storage, the product should be ventilated and dry to prevent moisture. 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