Definition of dark field microscopein microbiology

Light intensity can be measured using a light meter, which typically measures the amount of light in lux or foot-candles. These devices use sensors to detect the amount of light in a given area and display the results on a digital screen.

As light travels away from its source, it spreads out and becomes less intense. This is known as the inverse square law, which states that the intensity of light is inversely proportional to the square of the distance from the source.

Light intensity is determined by several factors, including the distance between the light source and the object, the brightness of the light source, and the properties of the medium through which the light travels (such as air or water).

Dark field microscopeprinciple

Light intensity can be affected by the type of light source, the distance from the light source, and the presence of any objects that may block or reflect the light. The color and surface properties of the object being illuminated can also impact light intensity.

The dark field microscope produces a light cone, which reaches the objective only when it is scattered by the sample. This reinforces the image contrast. The phase contrast microscope modifies the light trajectory so that part of the beam is modified by the sample and part is not. Making these two parts interfere creates a contrast, which allows to visualize samples even when they are transparent.

Light intensity refers to the amount of light energy that is present in a given area or space. It is measured in units of watts per square meter (W/m²) or lux (lx).