Optical radiation, electromagnetic wave, light source_electromagnetic wave and optical radiation of image measurement light source

The electromagnetic wave and optical radiation of the image measurement light source is a form of electromagnetic wave (electromagnetic wave), which is a kind of electromagnetic wave. The magnetic wave is a transverse wave. The electric field and the magnetic field vector are not only perpendicular to each other, but both are also perpendicular to the electromagnetic wave. The direction of propagation. The time for the polarity of the electric field and magnetic field to change for a period is called the period, the distance that the electromagnetic wave propagates in a cycle is called the wave (wavelength), and the number of repeated changes in the polarity of the electric field or magnetic field per unit time (the reciprocal of the period) is called Is the frequency of electromagnetic waves. There is the following relationship between them: e-vt u003d A/T (3-1 where r is the propagation speed of light in a vacuum, generally recorded approximately as 3×1oam/s, v, A, T-the frequency of light, Wavelength, period. Overview of the light source for image measurement The frequency range of electromagnetic waves covers a wide frequency range from cosmic rays to radio waves. It has been discovered and obtained! The wavelength of widely used electromagnetic waves can reach 10'm or more, or 10·Snm. Arrange these electromagnetic waves into a chart in the order of frequency or wavelength, which is called the electromagnetic spectrum, as shown in Figure 3-2. Within the electromagnetic spectrum range, only electromagnetic waves with a wavelength of 0.38～0.78 sonic n can cause the visual sense of the human eye. People call this range of electromagnetic radiation as optical radiation, and this wavelength is called the visible spectrum. Broadly speaking, X-ray, ultraviolet radiation, visible light and infrared radiation can all be called optical radiation. In the visible light range, the outer side of the violet light and the wavelength Electromagnetic waves that are less than 0.38 in n and invisible to the naked eye are called ultraviolet (ullra.iol.my) outside of the red light, and electromagnetic waves with wavelengths greater than 0.78Hm invisible to the naked eye are called infrared (infra superior dray). Wavelengths above \mnl Electromagnetic waves are collectively referred to as radio waves. The region from infrared to ultraviolet below a wavelength of 1 mm is called the optical zone. Among them, the wavelength between the optical zone and the radio wave zone is 1 to 0.1 mm (sometimes covering 0.06 mnr) Electromagnetic waves are called submillimeter waves in the field of radio wave research.