GB/T 40177-2021 PDF EnglishUS$110.00 · In stock · Download in 9 seconds
GB/T 40177-2021: Optics and optical instruments - Ophthalmology - Graduated dial scale Delivery: 9 seconds. True-PDF full-copy in English & invoice will be downloaded + auto-delivered via email. See step-by-step procedure Status: Valid
Similar standardsGB/T 40177-2021: Optics and optical instruments - Ophthalmology - Graduated dial scale---This is an excerpt. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.), auto-downloaded/delivered in 9 seconds, can be purchased online: https://www.ChineseStandard.net/PDF.aspx/GBT40177-2021GB NATIONAL STANDARD OF THE PEOPLE’S REPUBLIC OF CHINA ICS 11.040.70 C 40 GB/T 40177-2021 / ISO 8429:1986 Optics and optical instruments - Ophthalmology - Graduated dial scale (ISO 8429:1986, IDT) ISSUED ON: MAY 21, 2021 IMPLEMENTED ON: DECEMBER 01, 2021 Issued by: State Administration for Market Regulation; Standardization Administration of the PRC. Table of ContentsForeword ... 3 1 Scope ... 4 2 Description of the system ... 4 3 Example ... 5 Optics and optical instruments - Ophthalmology - Graduated dial scale1 ScopeThis Standard gives specifications for the angular coordinate system to be used in the design of scales, reticles or other display means incorporated in instruments for determining optical data on human eyes or corrective lenses for human eyes.2 Description of the systemThe coordinate system, specified in this Standard and sometimes called the TABO system, describes a) the angular orientation of the cylinder axis, when used to describe the refractive error of the eye or the refractive effect of a contact or spectacle lens; b) the angular orientation of the prism base, when used to describe the prismatic effect of a contact or spectacle lens in polar coordinates; c) the angular orientation of the principal curvature meridians, when used to describe the curvature of a surface such as the cornea or a lens. The coordinate system is the same whether it refers to the right eye or to the left eye. When used, the coordinate system is described as it appears to a person viewing the eyes and the spectacle lenses - correctly placed in front of the eyes - from outside. The zero axis of the coordinate system is horizontal and, in the case where the numbering is from 0° to 360°, it is the right-hand portion of the horizontal axis. The angular value increases in the counter-clockwise direction with 90° corresponding to the vertical axis. When used to define cylinder axis or orientation of principal curvature meridians, the angular value shall be expressed as a number between 0° and 180°. When used to define prism base orientation, the angular value shall be expressed as a number between 0° and 360°, marked by the point where the base of the prism touches the TABO circle. ......Source: Above contents are excerpted from the full-copy PDF -- translated/reviewed by: www.ChineseStandard.net / Wayne Zheng et al. Tips & Frequently Asked Questions:Question 1: How long will the true-PDF of English version of GB/T 40177-2021 be delivered?Answer: The full copy PDF of English version of GB/T 40177-2021 can be downloaded in 9 seconds, and it will also be emailed to you in 9 seconds (double mechanisms to ensure the delivery reliably), with PDF-invoice.Question 2: Can I share the purchased PDF of GB/T 40177-2021_English with my colleagues?Answer: Yes. The purchased PDF of GB/T 40177-2021_English will be deemed to be sold to your employer/organization who actually paid for it, including your colleagues and your employer's intranet.Question 3: Does the price include tax/VAT?Answer: Yes. Our tax invoice, downloaded/delivered in 9 seconds, includes all tax/VAT and complies with 100+ countries' tax regulations (tax exempted in 100+ countries) -- See Avoidance of Double Taxation Agreements (DTAs): List of DTAs signed between Singapore and 100+ countriesQuestion 4: Do you accept my currency other than USD?Answer: Yes. www.ChineseStandard.us -- GB/T 40177-2021 -- Click this link and select your country/currency to pay, the exact amount in your currency will be printed on the invoice. Full PDF will also be downloaded/emailed in 9 seconds.How to buy and download a true PDF of English version of GB/T 40177-2021?A step-by-step guide to download PDF of GB/T 40177-2021_EnglishStep 1: Visit website https://www.ChineseStandard.net (Pay in USD), or https://www.ChineseStandard.us (Pay in any currencies such as Euro, KRW, JPY, AUD).Step 2: Search keyword "GB/T 40177-2021". Step 3: Click "Add to Cart". If multiple PDFs are required, repeat steps 2 and 3 to add up to 12 PDFs to cart. Step 4: Select payment option (Via payment agents Stripe or PayPal). Step 5: Customize Tax Invoice -- Fill up your email etc. Step 6: Click "Checkout". Step 7: Make payment by credit card, PayPal, Google Pay etc. After the payment is completed and in 9 seconds, you will receive 2 emails attached with the purchased PDFs and PDF-invoice, respectively. Step 8: Optional -- Go to download PDF. Step 9: Optional -- Click Open/Download PDF to download PDFs and invoice. See screenshots for above steps: Steps 1~3 Steps 4~6 Step 7 Step 8 Step 9 |
