Ordinary Microscope (Light Microscope):
* Illumination: Uses visible light to illuminate the specimen.
* Magnification: Typically magnifies up to 1500x.
* Resolution: Limited by the wavelength of visible light, typically around 200 nanometers. This means it can't distinguish details smaller than that.
* Sample Preparation: Usually involves staining or other techniques to enhance contrast.
* Advantages: Relatively inexpensive, easy to use, and suitable for observing living specimens.
* Disadvantages: Limited resolution, cannot see extremely small objects.
Electron Microscope (EM):
* Illumination: Uses a beam of electrons to illuminate the specimen.
* Magnification: Can magnify up to 1,000,000x.
* Resolution: Significantly higher than light microscopes, reaching down to 0.1 nanometers. This allows for viewing of extremely small structures like atoms.
* Sample Preparation: Requires specialized preparation techniques that often involve dehydration and coating with a thin layer of metal.
* Advantages: Extremely high resolution, allows for visualization of very fine details.
* Disadvantages: Expensive, complex to operate, requires specialized sample preparation, and cannot be used to observe living specimens.
Types of Electron Microscopes:
* Transmission Electron Microscope (TEM): Uses a beam of electrons that passes through the sample, creating an image based on the electron transmission.
* Scanning Electron Microscope (SEM): Scans the surface of the sample with a focused beam of electrons, generating a 3D image.
Here's a table summarizing the key differences:
| Feature | Ordinary Microscope | Electron Microscope |
|---|---|---|
| Illumination | Visible light | Electron beam |
| Magnification | Up to 1500x | Up to 1,000,000x |
| Resolution | ~200 nm | ~0.1 nm |
| Sample Preparation | Staining, etc. | Dehydration, metal coating |
| Cost | Relatively inexpensive | Expensive |
| Complexity | Easy to use | Complex to operate |
| Live Specimens | Can observe | Cannot observe |
Ultimately, the choice between an ordinary microscope and an electron microscope depends on the specific application and the level of detail required.
