Microscopy Techniques: Optical Methods and Image Formation

This lecture provides an introduction to microscopy, focusing on optical methods and image formation. It begins with the basic components of a microscope, including the specimen, objective lens, and tube lens, explaining how these elements work together to form images. The instructor discusses the concept of Fourier transformation in microscopy, detailing how the objective lens creates a Fourier plane and how the tube lens produces an intermediate image. The lecture then explores different illumination techniques, such as point and annular illumination, and their effects on image quality, including darkfield and phase contrast microscopy. The importance of blocking zero order light for darkfield imaging and the use of phase plates for phase contrast are emphasized. The lecture concludes with a discussion on spectral measurements, explaining how to analyze light spectra after passing through an absorbing medium using monochromators and synchronous detectors. Overall, the lecture covers essential microscopy techniques and their applications in optical detection.