Editing Optical microscope (section)

{{short description|Microscope that uses visible light}}
{{Use dmy dates|date=March 2019}}

[[File:Scientists are working in the lab.9.jpg|thumb|300px| Scientist using an optical microscope in a laboratory]]

The '''optical microscope''', also referred to as a '''light microscope''', is a type of [[microscope]] that commonly uses [[visible spectrum|visible light]] and a system of [[lens (optics)|lenses]] to generate magnified images of small objects. Optical microscopes are the oldest design of microscope and were possibly invented in their present compound form in the 17th century. Basic optical microscopes can be very simple, although many complex designs aim to improve [[optical resolution|resolution]] and sample [[contrast (vision)|contrast]].{{Citation needed|date=August 2024}}

The object is placed on a '''stage''' and may be directly viewed through one or two [[eyepiece]]s on the microscope. In high-power microscopes, both eyepieces typically show the same image, but with a [[stereo microscope]], slightly different images are used to create a 3-D effect. A camera is typically used to capture the image ([[micrograph]]).{{Citation needed|date=August 2024}}

The sample can be lit in a variety of ways. Transparent objects can be lit from below and solid objects can be lit with light coming through ([[Bright-field microscopy|bright field]]) or around ([[Dark-field microscopy|dark field]]) the objective lens. [[Polarised light]] may be used to determine crystal orientation of metallic objects. [[Phase-contrast imaging]] can be used to increase image contrast by highlighting small details of differing refractive index.{{Citation needed|date=August 2024}}

A range of [[Objective (optics)|objective]] lenses with different magnification are usually provided mounted on a turret, allowing them to be rotated into place and providing an ability to zoom-in. The maximum magnification power of optical microscopes is typically limited to around 1000x because of the limited resolving power of visible light. While larger magnifications are possible no additional details of the object are resolved.{{Citation needed|date=August 2024}}

Alternatives to optical microscopy which do not use visible light include [[scanning electron microscopy]] and [[transmission electron microscopy]] and [[scanning probe microscopy]] and as a result, can achieve much greater magnifications.