Abstract: This disclosure relates to a digital holographic microscope which is robust to an external environment. According to an aspect of the present embodiment, there is provided an optical system for a digital holographic microscope, the optical system including a beam splitter which reflects a light radiated from a light source toward an object, or passes a light reflected from and traveling from the object; an objective lens focusing the light reflected by the beam splitter on the object; a transflective mirror which is located on the surface of the objective lens and is determined to be transparent or reflective depending on a polarization direction of a light incident to the transflective mirror; and a wave plate which converts the light passing through the beam splitter into a circularly polarized light.

Abstract: A SiAlON composite includes a SiAlON phase including ?-SiAlON phase, ?-SiAlON phase and grain boundary phase. The SiAlON composite is prepared from a starting powder mixture including a silicon nitride powder and at least one powder providing aluminum, oxygen, nitrogen, yttrium (Y) and erbium (Er) to the SiAlON composite. The SiAlON composite contains the SiAlON phase of at least 90 vol %, z-value of the ?-SiAlON phase ranges between 0.27 and 0.36 and thermal diffusivity of the SiAlON composite is equal to or greater than 2.4 (mm2/sec) and equal to or less than 5.2 (mm2/sec).

Abstract: A ceramic material includes of ?-sialon (Si(6-z)AlzOzN(8-z)), polytype 15R, an intergranular phase, and yttrium. The polytype 15R includes twin grains.

Abstract: A SiAlON composite includes a SiAlON phase including ?-SiAlON phase, ?-SiAlON phase and grain boundary phase. The SiAlON composite is prepared from a starting powder mixture including a silicon nitride powder and at least one powder providing aluminum, oxygen, nitrogen, yttrium (Y) and erbium (Er) to the SiAlON composite. The SiAlON composite contains the SiAlON phase of at least 90 vol %, z-value of the ?-SiAlON phase ranges between 0.27 and 0.36 and thermal diffusivity of the SiAlON composite is equal to or greater than 2.4 (mm2/sec) and equal to or less than 5.2 (mm2/sec).

Abstract: A ceramic material includes of ?-sialon (Si(6-z)AlzOzN(8-z)), polytype 15R, an intergranular phase, and yttrium. The polytype 15R includes twin grains.

Abstract: A cutting tool including a fine and uniform alumina-based substrate is disclosed herein. In an exemplary embodiment, the alumina-based substrate includes 0.1 to 25% by volume of one or more metal oxides, or 5 to 80% by volume of metal carbonitride and 0.01 to 10% by volume of one or more metal oxides. Metal constituting the metal oxide and the metal carbonitride is selected from the group consisting of elements from Groups III to VI (including La group and Ac group) of the periodic table, Mg and Co. The metal oxides added to alumina reside at the boundaries of alumina grains, thereby prohibiting the alumina grains from growing excessively during a sintering process.

Abstract: A cutting tool including a fine and uniform alumina-based substrate is disclosed herein. In an exemplary embodiment, the alumina-based substrate includes 0.1 to 25% by volume of one or more metal oxides, or 5 to 80% by volume of metal carbonitride and 0.01 to 10% by volume of one or more metal oxides. Metal constituting the metal oxide and the metal carbonitride is selected from the group consisting of elements from Groups III to VI (including La group and Ac group) of the periodic table, Mg and Co. The metal oxides added to alumina reside at the boundaries of alumina grains, thereby prohibiting the alumina grains from growing excessively during a sintering process.