2. 1674, Dutch cloth dealer van.leeuwenhoke personally polished a microscope with a magnification of 300 times to test the quality of cloth.
1886, German scientist Ernst. Abel and Carl. Chase made a similar microscope. The horseshoe-shaped base increases the stability of the microscope. The mirror at the bottom can collect and reflect light so that it can pass through the specimen above. Modern compound optical microscope has been able to enlarge the specimen to 1000 times.
3, 1933, German physicist Ernst. Luska invented the first electron microscope. This microscope images by emitting electrons through extremely thin sample slices. This is very useful for observing the internal structure of cells. TEM can enlarge the specimen by 500 thousand times.
4. From 65438 to 0965, the first commercial scanning electron microscope came out. It emits an electron beam to the surface of the specimen (instead of passing through the specimen), and then forms a fine three-dimensional image of the appearance of the specimen. SEM can enlarge the sample by 654.38+500,000 times.
5. 198 1 year, tunneling scanning microscope (STM) detects electron images escaping from the specimen surface. Scientists can use it to observe single molecules in the outer layer of cells. STM can enlarge the specimen by 654.38+00000 times.