BS EN ISO 10938. Ophthalmic optics. Chart displays for visual acuity measurements. Printed, projected & electronic OPHTHALMIC TEST EQUIPMENT, TEST CHARTS (OPHTHALMIC), PROJECTORS (IMAGE), OPHTHALMIC EQUIPMENT, OPHTHALMOLOGY, OPTICAL PROPERTIES OF MATERIALS, CONTRAST (OPTICAL), LUMINANCE, RESOLUTION, INSTRUCTIONS FOR USE, MARKING, TYPE TESTING