Swept Field Confocal Microscope

In 2006, Nikon enhanced its newest generation confocal microscope, the Nikon LiveScan Swept Field Confocal Microscope. The instrument represented an innovative approach to live cell confocal imaging. The microscope's enhanced capabilities stem from the design of a user selectable aperture for excitation and emission, with choices of multiple pinholes or a slit scanning position. The light path design of the instrument reduced crosstalk and noise inherent in live cell confocal instrumentation. This, coupled with the capability to scan very rapidly for very short excitation durations to prevent phototoxicity, made the microscope an excellent live cell imaging instrument. New solid state laser options, gas options, and high-powered water-cooled gas options were available.

What is a confocal microscope?

A confocal microscope is a type of optical imaging technique designed to increase optical resolution and contrast by using a spatial pinhole to eliminate out-of-focus light or background information in specimens that are thicker than the focal plane. It was invented by Marvin Minsky in 1957 and is commonly used in the scientific and industrial communities for its ability to produce high-resolution images and to reconstruct three-dimensional structures from the obtained images.

Confocal microscopy operates on the principle of point illumination and point detection. The light source illuminates a single point on the specimen, and only the light that is reflected or emitted from that exact point is collected by the detector. This means that all of the light that is not coming from the plane of focus (the confocal plane) is excluded.

A major advantage of confocal microscopy over conventional optical microscopy is its ability to control depth of field, eliminating or reducing background information. This results in sharp, high-resolution images that can be used to reconstruct a 3D image of the specimen.

In biological sciences, confocal microscopy is often used in conjunction with fluorescent staining techniques, where specific structures or components within a cell or tissue are labeled with fluorescent dyes or proteins. When illuminated, these fluorescent markers emit light, which is captured to create highly detailed, contrast-rich images.

However, due to the scanning mechanism, confocal microscopy can be slower than other forms of light microscopy, and the lasers used can also cause photobleaching or phototoxicity in live specimens. Despite these limitations, it remains a key tool in many areas of biological and materials research.