1590 – 1st telescope and microscope by placing two lenses in a tube 1667 – Studied several objects with microscope such as cork Depth:< 1 cm 1675 – 1st study in blood, cells and bacteria. optical microscope Advantages: High Sensitivity, Numerous Probes 1830 – Improvements by reducing problem with spherical aberration. HISTORY 1878 – The start of mathematical theory correlating resolution to the wavelength of light. Disadvantages: Low Spatial Resolution 1903 – ultramicroscope (study objects below the wavelength of light). 1932 – phase contrast microscope (colorless and transparent biological materials) 1940 – super-resolved fluorescence microscopy（breakthrough into nano scale）! ! ! microscope 1938 - Invention of the electron microscope. (Improvement of resolution and expanding borders of exploration) electron microscope 1897: Lamor Equation (Lamor frequency at which nucleus will absorb energy) 1981 – Invention of scanning tunneling microscope (3D images of objects to atomic level)(the sample must be conductive) STM more Nikola Tesla rotating magnetic fields basis related principles 1924: quantum nature of magnetic moment 1930: magnetic properties of atomic nuclei 1986 – Invention of Atomic Force Microscope (the sample can be non-conductive) AFM Biomedical imaging techniques based on MNR MRI 1944: discovery of NMR by Isidor Isaac Rabi Adavantages:High Spatial Resolution(useful for anatomical), Morphological and functional imaging （1969: prediction of MR body scanner) 1971: T1 and T2 relaxation measurements of excised nomral and cancerous tissue HISTORY Disadvantages:Low Sensitivity, Long Scans, Long Post-Processing Time radiography tomograpgy 1974: use of magnetic field gradients for spatial localization of NMR Signals 1980: prototype MR scanner developed Two-dimensional pictures 1963: 1st experiment of Tomographic device from 2D to 3D Advantages:High Contrast of Hard Tissue Structures, High Spatial Resolution( useful for anatomical) CT Fourier transform based on X-rays Radon transform HISTORY Disadvantages:Limited Soft Tissue Contrast, Ionizing Radiation, Low Sensitivity 1968: Hounsfield used power of computers at the time for complicated calculations and started the concept computed tomography (CT) 1971: first tomographic patient examination 1973: first commercial CT scanner on the market: EMI CT 1000 imaging theories higher energy X-rays Projection and backprojection spectral CT Spectral separation at detection 1953: 1st clinical positron imaging device Iterative reconstruction Advantages: High Sensitivity(eg.good at metabolic), Quantitative PET discovery Disadvantages:Radiation, Requires Cyclotron, Low Spatial Resolution discovered by Wilhelm C. Röntgen (1845-1923) on 8th November 1895 1973: 1st 32-detector circular array tomograph HISTORY 1974: 1st published human PET images using PET III with filtered backprojection algorithm Brain scan with [11C]-D-glucose 1978: Emission Computed Axial Tomograph (ECAT II) – 1st commercial PET scanner
