1595 - First compound microscope (involving more than one lens) invented by Zacharias and Hans Jansen. 

1604 - First use of the term ‘camera obscura’.

1665 - Publication of Robert Hooke's Micrographia

1685 - The first camera that was small and portable enough to be practical for photography was envisioned by Johann Zahn, though it would be almost 150 years before such an application was possible.

1816 - The first partially successful photograph of a camera image was made by Nicéphore Niépce, using a very small camera of his own making and a piece of paper coated with silver chloride, which darkened where it was exposed to light. 

1837 - Louis Daguerre created the first practical photographic process, which he named the daguerreotype. Daguerre treated a silver-plated sheet of copper with iodine vapor to give it a coating of light-sensitive silver iodide. After exposure in the camera, the image was developed by mercury vapor and fixed with a strong solution of sodium chloride.

1839 - Public unveiling of the daguerrotype.

1840 - Perfecting of the calotype by Henry Fox Talbot.

1882 - Nikola Tesla discovered the Rotating Magnetic Field. 

1885 - The use of photographic film was pioneered by George Eastman, who started manufacturing paper film before switching to celluloid in 1888-1889. 

1888 - Eastman’s first camera which he called the "Kodak," was first offered for sale. 

1905-13 - A number of manufacturers started to use 35mm film for still photography.

1913 - The first 35mm cameras available to the public, and reaching significant numbers in sales were the Tourist Multiple, in 1913, and the Simplex, in 1914.

1928 - The first practical reflex camera was the Franke & Heidecke Rolleiflex medium format TLR.

1950 - Spin echoes were first detected by Erwin Hahn. In magnetic resonance, a spin echo is the refocusing of spin magnetisation by a pulse of resonant electromagnetic radiation.

1952 - Herman Carr produced a one-dimensional NMR (nuclear magnetic resonance) spectrum as reported in his Harvard PhD thesis.

1959 - Jay Singer had studied blood flow by NMR relaxation time measurements of blood in living humans. Such measurements were not introduced into common medical practice until the mid-1980s, although a patent for a whole-body NMR machine to measure blood flow in the human body was already filed by Alexander Ganssen in early 1967.

1970s - Introduction of CT scans to medical imaging. During the 1970s a team led by John Mallard built the first full-body MRI scanner at the University of Aberdeen. 

1971 - Magnetic resonance imaging was invented by Paul C. Lauterbur in September. 

1973 - Theory behind MRI was published by Paul C. Lauterbur in March. 

1975 - The University of California, San Francisco Radiology Department founded the Radiologic Imaging Laboratory (RIL).

1977 - The first successful MRI scan was conducted on 3rd July.

1980 - On 28 August John Mallard’s team used their full-body MRI scanner to obtain the first clinically useful image of a patient's internal tissues, which identified a primary tumour in the patient's chest, an abnormal liver, and secondary cancer in his bones. Mallard and his team are credited for technological advances that led to the widespread introduction of MRI. In the same year, Paul Bottomley's team built the first whole-body MRI/MRS scanner. The results translated into the highly successful 1.5 T MRI product-line, with over 20,000 systems in use today.

1981 - RIL researchers, including Leon Kaufman and Lawrence Crooks, published Nuclear Magnetic Resonance Imaging in Medicine. In the 1980s the book was considered the definitive introductory textbook to the subject.

1988 - The first true portable digital camera that recorded images as a computerized file was likely the Fuji DS-1P, which recorded to a 2 MB SRAM memory card that used a battery to keep the data in memory. This camera was never marketed to the public. The move to digital formats was helped by the formation of the first JPEG and MPEG standards, which allowed image and video files to be compressed for storage.

1990 - BOLD-contrast imaging method of fMRI proof of concept provided by Seiji Ogawa and colleagues.

1992 - fMRI first used on humans by Kenneth Kwong and colleagues. 

2003 - Digital cameras have outsold film cameras ever since. Reflecting the fundamental importance and applicability of MRI in medicine, Paul C. Lauterbur of the University of Illinois at Urbana-Champaign and Sir Peter Mansfield of the University of Nottingham were awarded the Nobel Prize in Physiology or Medicine for their "discoveries concerning magnetic resonance imaging".