Overview
ISO 6198:1993 - "Micrographics - Readers for transparent microforms - Performance characteristics" defines essential performance and safety requirements for desktop readers with magnification ≤ 50:1 used with black-and-white roll microfilm (max width 35 mm), microfiche, jackets and image cards. The standard is explicit that it does not apply to reader-printers or pocket readers. ISO 6198 is intended to guide manufacturers, test laboratories, archivists and procurement teams on measurable reader performance and safe operation.
Key topics and technical requirements
- Magnification: Measured per ISO 7565; actual magnification must be within ±5% of the manufacturer’s stated magnification.
- Resolution & image quality: Minimum resolvable characters/patterns defined with ISO mitrotest charts (ISO No.1 and No.2); testing methods referenced to ISO 446 and ISO 3334.
- Geometric distortion: Pincushion/barrel distortion ≤ 0.5%; keystone/skew distortion ≤ 2% (tighter limits may be agreed for technical drawing use).
- Screen luminance and contrast:
- Minimum luminance: ≥ 35 cd/m² at any point in the measurement area; centre luminance ≥ 140 cd/m².
- Rear-projection luminance uniformity ratio typically ≤ 10 (≤15 for very large screens >540 mm diagonal); front-projection ratio ≤ 5.
- Noise and acoustics: Airborne noise measured per ISO 7779; recommended A-weighted sound pressure limits for library/quiet areas (e.g., normal viewing ≤ 50 dB, rapid motion ≤ 60 dB, impulsive noise ≤ 75 dB).
- Thermal limits: Film gate temperature ≤ 70 °C after 60 min operation; surface temperature limits for handles, external and internal parts (see standard table).
- Image handling & ergonomics: Correct orientation (upright, right-reading) for roll film, microfiche and image cards per referenced image formats; easy loading, indexing and interchangeable-component access without tools.
- Safety & construction: Compliance with IEC 950 for electrical safety, flame resistance and mechanical protection (shatterproof screens, rounded edges). Lamp access and replacement requirements included.
Practical applications and users
- Procurement specifications for libraries, archives, records management and museums selecting microform readers.
- Product design and quality assurance for manufacturers of microfilm/microfiche readers.
- Test labs and conformity assessment bodies conducting performance verification and acceptance testing.
- Facilities managing long-term access to archived documents where legibility, film preservation and operator safety are priorities.
Related standards
Key normative references in ISO 6198: ISO 7565, ISO 7779, ISO 6196 series (vocabulary), ISO 3334, ISO 446, ISO 9923, ISO 3272-3, ISO 6199 and IEC 950. These should be consulted together when specifying, testing or certifying microform readers.
Keywords: ISO 6198:1993, micrographics, microform reader performance, microfilm reader, microfiche reader, magnification tolerance, screen luminance, resolution, distortion, ISO microtest.