1. Microscopes: Microscopes are used to observe small structures such as cells, bacteria, and other microscopic organisms. There are different types of microscopes, such as optical, electron, and scanning probe microscopes, each with its own unique features and applications.

2. Telescopes: Telescopes are used to observe distant objects in space, such as planets, stars, galaxies, and other celestial bodies. There are different types of telescopes, such as refracting, reflecting, and radio telescopes, each with its own unique features and applications.

3. Spectrometers: Spectrometers are used to observe the spectral properties of matter, such as its composition, structure, and properties. They are commonly used in chemistry, physics, astronomy, and other scientific fields.

4. X-ray diffraction: X-ray diffraction is a technique used to observe the structure of matter at the atomic and molecular levels. It is commonly used in chemistry, physics, and materials science.

5. Magnetic resonance imaging (MRI): MRI is a medical imaging technique used to observe the internal structures of the body, such as the brain, muscles, and organs. It uses a magnetic field and radio waves to generate images of the body.

6. Thermal imaging: Thermal imaging is a technique used to observe the thermal properties of matter, such as its temperature and heat distribution. It is commonly used in industrial and military applications, as well as in building and home inspections.

7. Particle accelerators: Particle accelerators are used to observe the behavior and properties of subatomic particles, such as electrons, protons, and neutrons. They are commonly used in physics research and nuclear energy applications.

These are just some of the tools and instruments used to observe matter. The choice of the tool or instrument depends on the type of matter being observed, the properties or characteristics being measured, and the application or purpose of the observation.