Editing Optical microscope (section)

===Stage===
The stage is a platform below the objective lens which supports the specimen being viewed. In the center of the stage is a hole through which light passes to illuminate the specimen. The stage usually has arms to hold [[Microscope slide|slides]] (rectangular glass plates with typical dimensions of 25×75&nbsp;mm, on which the specimen is mounted).{{cn|date=December 2024}}

At magnifications higher than 100× moving a slide by hand is not practical. A mechanical stage, typical of medium and higher priced microscopes, allows tiny movements of the slide via control knobs that reposition the sample/slide as desired. If a microscope did not originally have a mechanical stage it may be possible to add one.{{cn|date=December 2024}}

All stages move up and down for focus. With a mechanical stage slides move on two horizontal axes for positioning the specimen to examine specimen details.{{cn|date=December 2024}}

Focusing starts at lower magnification in order to center the specimen by the user on the stage. Moving to a higher magnification requires the stage to be moved higher vertically for re-focus at the higher magnification and may also require slight horizontal specimen position adjustment. Horizontal specimen position adjustments are the reason for having a mechanical stage.{{cn|date=December 2024}}

Due to the difficulty in preparing specimens and mounting them on slides, for children it is best to begin with prepared slides that are centered and focus easily regardless of the focus level used.{{cn|date=December 2024}}