YY 0789-2024Laser therapeutic equipment - Q-switched ophthalmic laser equipment (English PDF)

1 Scope

YY 0789 is the mandatory standard for the Q-switched ophthalmic laser, the instrument used above all for YAG capsulotomy, cutting the clouded posterior capsule that develops after cataract surgery, and for iridotomy. Q-switching concentrates the pulse into nanoseconds, producing optical breakdown at the focus rather than heating, which is what lets it cut tissue inside the eye without an incision and also what makes precision in energy, pulse and aiming a safety requirement: the retina is a few millimetres behind the target. The YY prefix without /T makes compliance compulsory in China. For a manufacturer or an importer of ophthalmic YAG lasers for the Chinese market, this is the governing standard.

This document specifies the product classification and requirements for Q-switched ophthalmic laser therapeutic equipment and describes the corresponding test methods. This document applies to Q-switched ophthalmic laser therapeutic equipment (hereinafter referred to as therapeutic equipment).

2 Normative References

The contents of the following documents constitute indispensable clauses of this document through the normative references in the text. In terms of references with a specified date, only versions with a specified date are applicable to this document. In terms of references without a specified date, the latest version (including all the modifications) is applicable to this document.

GB 7247.1-2012 Safety of Laser Products - Part

3 Terms and Definitions

There are no terms or definitions that require definition in this document.

4 Product Classification

In accordance with the laser terminal pulse output mode, the therapeutic equipment can be divided into single pulse output and pulse train output; in accordance with the number of sub- pulses in a single output, the pulse train output mode can be divided into double pulse, triple

5.1.3.2 Single pulse output laser pulse width If the therapeutic equipment has a single pulse output mode, under the single pulse output mode, the deviation between the measured value of the laser pulse width and the nominal value shall not exceed 20%; the nominal range of the laser pulse width can also be given, and the measured value shall be within the nominal range. The nominal value and range of the pulse width shall not be greater than 6 ns.

5.1.3.3 Laser pulse train width If the therapeutic equipment has a pulse train output mode, under each pulse train output mode, the deviation between the measured value of the laser pulse train width and the nominal value shall not exceed 20%; the nominal range of the laser pulse train width can also be given, and the measured value shall be within the nominal range.

5.1.3.4 Sub-pulse width and sub-pulse interval If the therapeutic equipment has a pulse train output mode, the deviation between the measured value of the sub-pulse width and the nominal value shall not exceed 20%; the nominal range of the sub-pulse width can also be given, and the measured value shall be within the nominal range. Both the nominal value and range of the sub-pulse width shall not be greater than 6 ns. At the same time, under each pulse train output mode, the deviation between the measured value of the sub-pulse interval and the nominal value shall not exceed 20%; the nominal range of the sub-pulse interval can also be given, and the measured value shall be within the nominal range.

5.1.3.5 Pulse (pulse train) repetition frequency or interval If the pulse (pulse train) output of the therapeutic equipment is repeatable, the deviation between the measured value of the pulse (pulse train) repetition frequency or interval and the nominal value shall not exceed 20%.

5.1.4 Terminal output energy of laser pulse (pulse train) If the terminal output energy of the laser pulse (pulse train) cannot be adjusted, under each laser pulse output mode, the deviation between the measured value of the terminal output energy of the laser pulse (pulse train) and the nominal value shall not exceed 20%. If the terminal output energy of the laser pulse (pulse train) is adjustable, under each laser pulse output mode, the deviation between the measured value in the adjustment range and the preset value shall not exceed 20%.

5.1.5 Laser output energy reproducibility The laser output energy reproducibility shall not exceed 20%.

5.1.6 Laser output beam convergence angle The deviation between the measured value of the laser output beam convergence angle and the nominal value shall not exceed 20%; the nominal range of the beam convergence angle can also be given, and the measured value shall be within the nominal range.

5.1.7 Laser output focal spot diameter The deviation between the measured value of the laser output focal spot diameter and the nominal value shall not exceed 20%; a nominal range of the focal spot diameter can also be given, and the measured value shall be within the nominal range.

5 Requirements...