Optical Microscopy

Microscopy

In microscopy, we use an optical instrument known as a microscope to observe and magnify small objects through the lens, enabling the observer to examine the minute structures closely. The word “microscope” comes from the Latin “microscopium,” which is derived from the Greek words “mikros,” meaning “small,” and “skopein,” meaning “to look at.” While the microscope has many parts like an eyepiece, objective lens, aperture, nose piece, stage, and microscopic illuminator, the most important is its lenses. It is through the lenses that the image of the object can be magnified and viewed in detail. Two important parameters in microscopy are magnification and resolution. Magnification measures the total enlargement of the image of an object. The magnification factor varies between 5x-30x. Resolution is the ability of a microscope to differentiate the details of a sample. Microscopy comes in various types, each serving specific purposes. They find applications in research, metallurgy, educational institutions, crime investigation, etc. The different types of microscopy are:...

Optical Microscopy

Optical microscopy, also known as light microscopy, is a widely used technique that uses visible light and lenses to observe and magnify samples. A sample is illuminated with visible light, and the light interacts with the specimen to provide detailed information about its structure. The interaction of light with the sample can be modified using various techniques, resulting in different types of optical microscopes. These are as follows:...

Electron Microscopy

Electron microscopy is a powerful technique that uses a beam of accelerated electrons instead of light to magnify and view samples. The image obtained is of high resolution and highly magnified as compared to an image obtained in optical microscopy. There are two main types of electron microscopes:...

Ultraviolet Microscopy

Ultraviolet (UV) microscopy is a specialized technique that uses ultraviolet light instead of visible light to illuminate and observe samples. UV microscopy takes advantage of the shorter wavelength and higher energy of the UV light to provide images with enhanced resolution and improved contrast compared to traditional visible light microscopy....

Scanning Probe Microscopy

Scanning probe microscopy forms the image of the surface using a probe tip that scans the sample. It allows for imaging and manipulation of surfaces at the nanoscale. Unlike optical microscopy, which uses light, or electron microscopy which uses electron beams, scanning probe microscopy uses a physical probe to interact with the surface of a sample. A probe tip is attached to a cantilever and used to scan the surface of a sample. The probe tip is sharp and precisely moves across the sample surface, scanning each atom. The tip is positioned close to the sample surface, causing the cantilever to undergo deflection in response to forces. This deflection distance is measured using a laser. After the scanning process is complete, The resulting measurements are used to generate an image on a computer....

Infrared microscopy

Infrared microscopy is a technique that uses infrared light to study and analyze samples at the micro level. Unlike other optical microscopy that uses absorbent glass optics, infrared microscopy uses reflective optics to allow the microscope to cover the entire spectral range of infrared light. Infrared light has longer wavelengths than visible light providing detailed information about the chemical composition and molecular structure of materials....

Laser Microscopy

Laser microscopy is a fast-growing field that uses laser light as the source of illumination for imaging and analyzing samples at a microscopic level. Laser microscopy offers several advantages over traditional microscopy techniques, including enhanced resolution, sensitivity, and specificity. The laser light interacts with the sample, and the resulting signals, such as fluorescence or scattering, are collected and analyzed to generate an image or obtain information about the sample’s properties....

​Photoacoustic Microscopy

Photoacoustic microscopy (PAM) combines the principles of ultrasound and laser-induced photoacoustic effect to observe the samples. It utilizes laser pulses to generate photoacoustic waves, which are then detected and used to reconstruct high-resolution images. When a sample absorbs laser light, it undergoes rapid thermal expansion, leading to the generation of acoustic waves. Ultrasound transducers or detectors capture the generated acoustic waves, which are then converted into electrical signals. The acquired signals are processed and used to reconstruct images based on the depth and intensity of the photoacoustic waves....

FAQs on Microscopy

Q1: What are the different types of microscopy?...