1. A tungsten-based sintered material having high strength and high hardness comprising nickel (Ni) in a range from 0.2 to 1.5% by mass, yttrium oxide (Y2O3) in a range from 0.1 to 1% by mass, and vanadium carbide (VC) in a range from 0.05 to 0.5% by mass, the balance being tungsten (W); wherein
tungsten phases are sinter-bonded;
fine nickel phase and yttrium oxide phase which have a largest particle diameter of 5 \u03bcm or less are distributed at boundaries of the tungsten phases; and
a largest particle diameter of the tungsten phase is 20 \u03bcm or less.
2. A tungsten-based sintered material having high strength and high hardness comprising: nickel (Ni) in a range from 0.2 to 1.5% by mass, yttrium oxide (Y2O3) in a range from 0.1 to 1% by mass, and at least one of cobalt (Co) and iron (Fe) in a range from 0.01 to 0.5% by mass, the balance being tungsten (W); wherein
tungsten phases are sinter-bonded;
any one of fine Ni\u2014Co alloy phase, Ni\u2014Fe alloy phase, and Ni\u2014Co\u2014Fe alloy phase which have a largest particle diameter of 5 \u03bcm or less and yttrium oxide phase which has a largest particle diameter of 5 \u03bcm or less are distributed at boundaries of the tungsten phases; and
a largest particle diameter of the tungsten phase is 30 \u03bcm or less.
3. A tungsten-based sintered material having high strength and high hardness comprising: nickel (Ni) in a range from 0.2 to 1.5% by mass, yttrium oxide (Y2O3) in a range from 0.1 to 1% by mass, vanadium carbide (VC) in a range from 0.05 to 0.5% by mass, and at least one of cobalt (Co) and iron (Fe) in a range from 0.01 to 0.5% by mass, the balance being tungsten (W); wherein
tungsten phases are sinter-bonded;
any one of fine Ni\u2014Co alloy phase, Ni\u2014Fe alloy phase, and Ni\u2014Co\u2014Fe alloy phase which have a largest particle diameter of 5 \u03bcm or less and yttrium oxide phase which has a largest particle diameter of 5 \u03bcm or less are distributed at boundaries of the tungsten phases; and
a largest particle diameter of the tungsten phase is 20 \u03bcm or less.
4. A tungsten-based sintered material having high strength and high hardness comprising: nickel (Ni) in a range from 0.2 to 1.5% by mass, yttrium oxide (Y2O3) in a range from 0.1 to 1% by mass, and at least one of molybdenum (Mo), chromium (Cr), niobium (Nb), and rhenium (Re): 0.5 to 4%; the balance being tungsten (W); wherein
W-M alloy phases (wherein M denotes at least one of Mo, Cr, Nb, and Re) are sinter-bonded;
any one of fine Ni phase having a largest particle diameter of 5 \u03bcm or less and yttrium oxide phase having a largest particle diameter of 5 \u03bcm or less are distributed at boundaries of the W-M alloy phases; and
a largest particle diameter of the W-M alloy phase is 30 \u03bcm or less.
5. A tungsten-based sintered material having high strength and high hardness comprising: nickel (Ni) in a range from 0.2 to 1.5% by mass, yttrium oxide (Y2O3) in a range from 0.1 to 1% by mass, at least one of molybdenum (Mo), chromium (Cr), niobium (Nb), and rhenium (Re): 0.5 to 4%; and vanadium carbide (VC) in a range from 0.05 to 0.5% by mass, the balance being tungsten (W); wherein
W-M alloy phases (wherein M denotes at least one of Mo, Cr, Nb, and Re) are sinter-bonded;
any one of fine Ni phase having a largest particle diameter of 5 \u03bcm or less and yttrium oxide phase having a largest particle diameter of 5 \u03bcm or less are distributed at boundaries of the W-M alloy phases; and
a largest particle diameter of the W-M alloy phase is 15 \u03bcm or less.
6. A tungsten-based sintered material having high strength and high hardness comprising: nickel (Ni) in a range from 0.2 to 1.5% by mass, yttrium oxide (Y2O3) in a range from 0.1 to 1% by mass, at least one of molybdenum (Mo), chromium (Cr), niobium (Nb), and rhenium (Re): 0.5 to 4%; and at least one of cobalt (Co) and iron (Fe) in a range from 0.01 to 0.5% by mass, the balance being tungsten (W); wherein
W-M alloy phases (wherein M denotes at least one of Mo, Cr, Nb, and Re) are sinter- bonded;
any one of fine Ni-Co alloy phase, Ni-Fe alloy phase, and Ni-Co-Fe alloy phase which have a largest particle diameter of 5 \u03bcm or less and yttrium oxide phase which has a largest particle diameter of 5 \u03bcm or less are distributed at boundaries of the tungsten phases; and
a largest particle diameter of the W-M alloy phase is 30 \u03bcm or less.
7. A tungsten-based sintered material having high strength and high hardness comprising: nickel (Ni) in a range from 0.2 to 1.5% by mass, yttrium oxide (Y2O3) in a range from 0.1 to 1% by mass, at least one of molybdenum (Mo), chromium (Cr), niobium (Nb), and rhenium (Re): 0.5 to 4%; vanadium carbide (VC) in a range from 0.05 to 0.5% by mass, and at least one of cobalt (Co) and iron (Fe) in a range from 0.01 to 0.5% by mass, the balance being tungsten (W); wherein
W-M alloy phases (wherein M denotes at least one of Mo, Cr, Nb, and Re) are sinter- bonded;
any one of fine Ni phase having a largest particle diameter of 5 \u03bcm or less and yttrium oxide phase having a largest particle diameter of 5 \u03bcm or less are distributed at boundaries of the W-M alloy phases; and
a largest particle diameter of the W-M alloy phase is 15 \u03bcm or less.
8. A hot press mold for optical glass lenses composed at least partly of the tungsten-based sintered material according to any one of claims 1 to 7.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An imaging apparatus comprising:
an imaging device that includes a plurality of pixels;
a first curtain configured to travel to block incidence of light on the imaging device;
a second curtain configured to permit the incidence of light on the imaging device earlier than traveling of the first curtain;
and
circuitry configured to:
sequentially resetting reset-scan lines of the imaging device earlier than the traveling of the first curtain;
correct a line reset-scanning time associated with the sequentially resetting on the basis of a movement amount of the imaging device having been made to move on the basis of a camera shake detection result;
correct an image captured by an electronic shutter operation performed by the first curtain and the sequentially resetting using a correction gain based on the movement amount of the imaging device and a slit width; and
calculate the correction gain from a difference between an image captured by a mechanical shutter operation performed by the traveling of the first curtain and the second curtain and an image captured by the electronic shutter operation and corrects the image captured by the electronic shutter operation using the calculated correction gain.
2. The imaging apparatus according to claim 1, wherein the circuitry is further configured to correct the line reset-scanning time associated with the sequentially resetting on the basis of the movement amount of the imaging device and a traveling position of the first curtain.
3. The imaging apparatus according to claim 1, wherein the circuitry is further configured to control the line reset-scanning time when an image capturing operation is performed at a shutter speed higher than a first threshold value.
4. The imaging apparatus according to claim 1, wherein the circuitry is further configured to store a plurality of correction tables each specifying a correction gain
and select one of the plurality of correction tables which corresponds to the movement amount of the imaging device and the slit width and correct the image captured by the electronic shutter operation using a correction gain associated with the selected correction table.
5. A shutter operation correcting method comprising:
correcting, by processing circuitry, a line reset-scanning time on the basis of a movement amount of an imaging device having been made to move on the basis of a camera shake detection result;
sequentially resetting, by the processing circuitry, reset-scan lines of the imaging device at the corrected line reset-scanning time, which is earlier than the traveling of a first curtain that blocks incident light on the imaging device;
correcting an image captured by an electronic shutter operation performed by the first curtain and the sequentially resetting using a correction gain based on the movement amount of the imaging device and a slit width;
storing the captured image;
calculating the correction gain from a difference between an image captured at a shutter speed higher than a first threshold value and an image captured at a shutter speed lower than the higher shutter speed out of stored images; and
correcting the captured image at the higher shutter speed using the calculated correction gain.