what is the limit of resolution of the human eye in micrometers
~55-75 micrometers ~ 0.116 mm
title: Micrometre text: Micrometre The micrometre (International spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known by the previous name micron, is an SI derived unit of length equaling (SI standard prefix "micro-" = 10); that is, one millionth of a metre (or one thousandth of a millimetre, 0.001 mm, or about 0.000039 inch). The micrometre is a common unit of measurement for wavelengths of infrared radiation as well as sizes of biological cells and bacteria, and for grading wool by the diameter of the fibres. The width of a single title: Human eye text: The upper end of the range is given in terms of normal visual performance as 10 cd/m (100,000,000 or one hundred million candelas per square meter). The eye includes a lens similar to lenses found in optical instruments such as cameras and the same physics principles can be applied. The pupil of the human eye is its aperture; the iris is the diaphragm that serves as the aperture stop. Refraction in the cornea causes the effective aperture (the entrance pupil) to differ slightly from the physical pupil diameter. The entrance pupil is typically about 4 mm in diameter, although it title: Visual acuity text: low light is achieved in near peripheral vision The maximum angular resolution of the human eye at a distance of 1 km is typically 30 to 60 cm. This gives an angular resolution of between 0.02 and 0.03 degrees, which is roughly 1.2–1.8 arc minutes per line pair, which implies a pixel spacing of 0.6–0.9 arc minutes. 6/6 vision is defined as the ability to resolve two points of light separated by a visual angle of one minute of arc, or about 320–386 pixels per inch for a display on a device held 25 to 30 cm from the eye. title: Micrometre text: must recognize the micro sign as well. Most fonts use the same glyph for the two characters. Micrometre The micrometre (International spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known by the previous name micron, is an SI derived unit of length equaling (SI standard prefix "micro-" = 10); that is, one millionth of a metre (or one thousandth of a millimetre, 0.001 mm, or about 0.000039 inch). The micrometre is a common unit of measurement for wavelengths of infrared radiation as well as sizes of biological cells title: Least distance of distinct vision text: Least distance of distinct vision In optometry, the least distance of distinct vision (LDDV) or the reference seeing distance (RSD) is the closest someone with "normal" vision (20/20 vision) can comfortably look at something. In other words, LDDV is the minimum comfortable distance between the naked human eye and a visible object. magnifying power ("M") of a lens with focal length ("f" in millimeters) when viewed by the naked human eye: The power of a lens or curved mirror in Dioptres is calculated by the relationship D=1/F, where D is the power in Dioptres and F is the focal length