caa a22 4500 445305460 CHVBK 20180317142611.0 cr unu---uuuuu 170323e20110901xx s 000 0 eng 10.1007/s10762-011-9812-7 doi (NATIONALLICENCE)springer-10.1007/s10762-011-9812-7 Improving Spatial Resolution of Real-Time Terahertz Near-Field Microscope [Elektronische Daten] [Atsushi Doi, François Blanchard, Tomoko Tanaka, Koichiro Tanaka] Terahertz (THz) wave imaging for biomaterial samples such as cells requires real-time acquisition and high spatial resolution beyond the diffraction limit. The existing THz near-field microscopes are based on raster-scanning techniques, and are therefore not able to image and trace morphological changes in a large area. With the recent advances in high-power THz sources, we demonstrated how to achieve high spatial resolution over a large size using a conventional charge-coupled-device (CCD) camera with the electro-optic (EO) sampling technique. In this paper, we determine a limiting factor that restricts spatial resolution in our near-field microscope. By calculating the imaging performance of the probe beam together with THz wave diffraction, we show that the most relevant factor is the diffraction inside the EO crystal. Near-field imaging of metal patterns using EO crystals with different thicknesses supports this calculation. A thin EO crystal is essential for achieving THz images with high spatial resolution. Springer Science+Business Media, LLC, 2011 Submillimeter wave nationallicence Microscope nationallicence Ultrafast optics nationallicence Near field nationallicence Imaging nationallicence Spectroscopy nationallicence Doi Atsushi Olympus Corporation, 2-3 Kuboyama-cho, 192-8512, Hachioji-shi, Tokyo, Japan aut Blanchard François CREST, Japan Science and Technology Agency, 332-0012, Kawaguchi, Saitama, Japan aut Tanaka Tomoko CREST, Japan Science and Technology Agency, 332-0012, Kawaguchi, Saitama, Japan aut Tanaka Koichiro CREST, Japan Science and Technology Agency, 332-0012, Kawaguchi, Saitama, Japan aut Journal of Infrared, Millimeter, and Terahertz Waves Springer US; http://www.springer-ny.com 32/8-9(2011-09-01), 1043-1051 1866-6892 32:8-9<1043 2011 32 10762 https://doi.org/10.1007/s10762-011-9812-7 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10762-011-9812-7 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Doi Atsushi Olympus Corporation, 2-3 Kuboyama-cho, 192-8512, Hachioji-shi, Tokyo, Japan aut NATIONALLICENCE 700 1- Blanchard François CREST, Japan Science and Technology Agency, 332-0012, Kawaguchi, Saitama, Japan aut NATIONALLICENCE 700 1- Tanaka Tomoko CREST, Japan Science and Technology Agency, 332-0012, Kawaguchi, Saitama, Japan aut NATIONALLICENCE 700 1- Tanaka Koichiro CREST, Japan Science and Technology Agency, 332-0012, Kawaguchi, Saitama, Japan aut NATIONALLICENCE 773 0- Journal of Infrared, Millimeter, and Terahertz Waves Springer US; http://www.springer-ny.com 32/8-9(2011-09-01), 1043-1051 1866-6892 32:8-9<1043 2011 32 10762 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer