Digital and Video Microscopes

Digital and video microscopes are instruments that use digital technology to magnify images of objects. They include built-in cameras and a series of high-powered lenses that provide superior image quality and resolution. Some digital and video microscopes require users to view objects through a standard eyepiece. Others provide a computer interface that displays images on a monitor. Image analysis processing software allows adjustments to both linear dimensions and resolution. Total magnification, the ratio of the image size to the actual object, is usually determined by linear measurement. This specification represents the device’s entire magnification range, including both eyepiece magnification and objective magnification.

There are three grades of digital and video microscopes: student, benchtop, and research. Student microscopes are the smallest and least expensive type of device. They are capable of advanced techniques and are designed for bright field, dark field, and phase contrast examinations. Benchtop microscopes are used in industries such as textiles and animal husbandry. They provide a range of examination techniques, but can perform only a few methods at one time. Research microscopes are large devices that weight between 30 kg and 50 kg and contain complex optical, mechanical, and electronics systems. These devices include multiple cameras and can perform the widest range of simultaneous examinations. Many research microscopes contain built-in computers that control the cameras and functions such as focus management and image processing. 

Digital and video microscopes use several imaging technologies. Acoustic and ultrasonic devices use sound waves and are suitable for non-destructive testing. Compound microscopes, which use a single light path, are designed for viewing very small specimens such as cells. Fluorescent and ultraviolet (UV) microscopes use high-energy, short-wavelength light to excite electrons within specific molecules. Inverted microscopes place the illumination system above the stage and the lens system below the stage for viewing thick specimens. Laser or confocal microscopes use a laser of light to image one plane at a time. Polarizing microscopes position polarizers perpendicular to each other so that the only light that passes through the specimen reaches the eyepiece. Portable field microscopes are lightweight devices that include an energy source such as a battery. Scanning electron microscopy (SPM) forms images with a detector that is synchronized with a focused electron beam. Scanning probe microscopes (SPMs), atomic force microscopes (AFMs), and transmission electron microscopes (TEMs) are also available. Microwave microscopes use electromagnetic radiation, which has a long wavelength between 1 mm and 30 cm. Stereomicroscopes use two different paths of light so that users can view specimens in three dimensions. 

There are a variety of configurations and applications for digital and video microscopes. Gemological devices use polarized light with lower magnifying powers to produce sharp, bright images in a wide field of view. Medical and forensic microscopes are often hands-free and binocular. Measuring microscopes are used in applications such as tool making. Biological and life science microscopes transmit light or use environmental scanning electron microscopy (SEM). Digital and video microscopes are also used to examine the layers in semiconductor wafers and fabricated integrated circuit (IC) components. These digital and video microscopes provide superior precision and throughput.