Overview
ISO 11884-2:2007 - Optics and photonics - Minimum requirements for stereomicroscopes - Part 2: High performance microscopes specifies minimum technical, environmental and safety requirements for high performance stereomicroscopes. Published in 2007 (second edition), it applies to type testing and product specification; it is explicitly not applicable to operation microscopes. The standard sets objective criteria for optical/mechanical performance, environmental robustness, testing methods and accompanying documentation.
Key Topics and Requirements
- Optical and mechanical specifications (Table 1)
- Total magnification tolerance: ±7.5%
- Difference between left and right optical systems: ≤1.5% (magnification) and specified angular tolerances (e.g., vertical ≤15′)
- Centre alignment limits for primary image and eyepiece diaphragm differences (millimetre-level tolerances)
- Focus shift with magnification change and depth-of-field requirements (depth-of-field formula referenced)
- Minimum resolution in the field centre: 2 500 × NA line pairs/mm (specified in the standard)
- Eyepiece adjustments: interpupillary distance 55–75 mm, dioptre adjustment +5 D to –5 D
- Environmental conditions
- Conditions of use: Temperature +10 °C to +40 °C, relative humidity ≤85%, atmospheric pressure 700–1 060 hPa, shock 10 g/6 ms.
- Storage and transport limits defined (e.g., transport: –40 °C to +70 °C, sinusoidal vibration and shock/bump severity).
- Safety and testing
- Safety testing to IEC 61010-1.
- Type tests and measurement procedures referenced to ISO 15227 (stereomicroscope testing) and environmental methods in ISO 9022.
- Measurement devices used for verification must have errors