9012 - Microscopes other than optical microscopes; diffraction apparatus; parts and accessories thereof:

Category 9012 encompasses microscopes that do not rely on visible light for magnification, as well as diffraction apparatus. This includes electron microscopes (both transmission and scanning), scanning probe microscopes (such as atomic force microscopes and scanning tunneling microscopes), and other advanced imaging systems that utilize particle beams or surface probing techniques to generate magnified images of extremely small structures. Diffraction apparatus in this category refers to instruments designed to study the diffraction patterns of waves or particles, often used in conjunction with other specialized microscopes or for material analysis.

Distinguishing this category from optical microscopes (classified elsewhere in Chapter 90) is the fundamental principle of operation. Optical microscopes utilize visible light and lenses to magnify specimens, whereas the instruments in 9012 employ non-optical methods. Furthermore, while other chapters in the HTS may cover scientific instruments for measurement or analysis, 9012 specifically targets magnifying instruments and diffraction apparatus based on their unique technological principles and design.

This category is further divided to accommodate the specific components of these advanced instruments. Subcategory 9012.10.00.00 covers the complete microscopes and diffraction apparatus themselves, representing the primary functional units. Subcategory 9012.90.00.00 is reserved for parts and accessories that are designed for use with these specific non-optical microscopes and diffraction apparatus, ensuring that components like specialized detectors, sample holders, or beam sources are correctly classified.