Abstract: A processing method for an additively manufactured article, the processing method including: accommodating an additively manufactured article containing metal and a medium made of metal in a barrel polishing device; and reducing a roughness of a surface of the additively manufactured article and applying a residual stress to the additively manufactured article by stirring the additively manufactured article and the medium, in which a surface of the medium includes a curved surface.

Abstract: A projection system includes a first optical system and a second optical system disposed on an enlargement side of the first optical system. The first optical system includes a first lens group having positive power, a second lens group disposed on the enlargement side of the first lens group and having negative power, and an optical path deflector disposed between the first lens group and the second lens group. The second optical system includes a reflection member having a concave reflection surface. The second lens group includes three aspherical lenses. Conditional Expression (1) below is satisfied, 0.25<|F|×FNO/Ymax<0.5??(1) where F represents the focal length of the entirety of the projection system, FNO represents the F number of the projection system, and Ymax represents a maximum image height in a reduction-side conjugate plane.

Abstract: An imaging lens includes a first lens having positive refractive power; a second lens having positive refractive power; a third lens having negative refractive power; a fourth lens having negative refractive power; a fifth lens; a sixth lens; a seventh lens; an eighth lens; and a ninth lens having negative refractive power, arranged in this order from an object side to an image plane side. The ninth lens is formed in a shape so that a surface thereof on the image plane side has an aspherical shape having an inflection point.

Abstract: A projection system includes a first lens group having negative power, a second lens group having positive power, a third lens group having positive power, a fourth lens group having negative power, a fifth lens group having positive power, a sixth lens group having positive power, and a seventh lens group having positive power that are sequentially arranged from the enlargement side toward the reduction side. The second lens group, the third lens group, the fourth lens group, the fifth lens group, and the sixth lens group are moved with the first lens group and the seventh lens group fixed to change the magnification of the projection system.

Abstract: A projection optical device includes an incident side optical path on which image light is made incident from a image generation device, a bending member configured to bend the image light having passed through the incident side optical path, an emission side optical path on which the image light bent by the bending member is made incident, the emission side optical path being disposed side by side with the light source device, and a reflection element provided on the emission side optical path and configured to reflect the image light made incident thereon and project the image light to the outside of the exterior housing. The absolute value of f2/f1 satisfies the following expression when a focal length of the projection optical device is represented as f1 and a focal length of the reflection element is represented as f2. 4.0<|f2/f1|<20.0.

Abstract: A projection system includes a first optical system and a second optical system. The second optical system includes a first lens group disposed on an enlargement side of an intersection position where a chief ray of an off-axis beam having a maximum angle of view intersects with an optical axis of the projection system in the second optical system, a second lens group disposed on the reduction side of the intersection position and having negative power, and a third lens group disposed on the reduction side of the second lens group and having positive power. The second lens group includes a first lens having positive power, a second lens disposed on the reduction side of the first lens and having positive power, and a third lens disposed on the reduction side of the second lens and having negative power. The third lens group includes two lenses each having positive power.

Abstract: An imaging lens includes a first lens having positive refractive power; a second lens having negative refractive power; a third lens having negative refractive power; a fourth lens having positive refractive power; a fifth lens; a sixth lens; a seventh lens; an eighth lens; and a ninth lens having negative refractive power, arranged in this order from an object side to an image plane side. The ninth lens is formed in a shape so that a surface thereof on the image plane side has an aspherical shape having an inflection point.

Abstract: There is provided a compact imaging lens configured to properly correct aberrations. The imaging lens includes, in order from an object side to an image side, a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, a third lens L3 with positive refractive power, a fourth lens L4 with positive refractive power, a fifth lens L5, a sixth lens L6, a seventh lens L7 with positive refractive power, and an eighth lens L8 with negative refractive power. The eighth lens L8 is formed in a shape of a meniscus lens in a paraxial region, and has an aspheric image-side surface having at least one inflection point. In addition, the following conditional expressions are satisfied: ?5.00<f2/f<?2.00 10.00<f4/f<25.00 where f: a focal length of the overall optical system of the imaging lens, f2: a focal length of the second lens, and f4: a focal length of the fourth lens.

Abstract: An imaging lens includes a first lens having positive refractive power; a second lens having negative refractive power; a third lens having negative refractive power; a fourth lens having negative refractive power; a fifth lens; a sixth lens; a seventh lens; an eighth lens; and a ninth lens having negative refractive power, arranged in this order from an object side to an image plane side. The ninth lens is formed in a shape so that a surface thereof on the image plane side has an aspherical shape having an inflection point.

Abstract: An imaging lens includes a first lens having positive refractive power; a second lens having positive refractive power; a third lens having negative refractive power; a fourth lens having positive refractive power; a fifth lens; a sixth lens; a seventh lens; an eighth lens; and a ninth lens having negative refractive power, arranged in this order from an object side to an image plane side. The ninth lens is formed in a shape so that a surface thereof on the image plane side has an aspherical shape having an inflection point.

Abstract: An imaging lens includes a first lens; a second lens; a third lens having negative refractive power; a fourth lens; a fifth lens; a sixth lens; and a seventh lens, arranged in this order from an object side to an image plane side. The sixth lens is formed in a shape so that a surface thereof on the image plane side is concave at a paraxial region thereof. The seventh lens is formed in a shape so that a surface thereof on the image plane side is aspheric. The first lens and the second lens have a specific composite focal length. The third lens have a specific focal length.

Abstract: An imaging lens includes a first lens; a second lens; a third lens having negative refractive power; a fourth lens having positive refractive power; a fifth lens; a sixth lens; and a seventh lens, arranged in this order from an object side to an image plane side. The first lens has at least one aspheric surface. The fifth lens has two aspheric surfaces. The sixth lens is formed in a shape so that a surface thereof on the object side is convex at a paraxial region thereof and a surface thereof on the image plane side is concave at a paraxial region thereof. The seventh lens has two aspheric surfaces.

Abstract: A projection system includes a first optical system and a second optical system sequentially arranged from a reduction side toward an enlargement side. The second optical system includes an optical element having a concave reflection surface and a first lens having negative power, the optical element and the first lens sequentially arranged from the reduction side toward the enlargement side. The projection system satisfies Conditional Expressions (1) and (2) below. 3.5 ? LL + MR / imy × TR × 1 / NA ? 6.0 ­­­(1) TR ? 0 .

Abstract: A projection system includes a first lens group having refractive power, an aperture stop, and a second lens group having refractive power sequentially arranged from the enlargement side toward the reduction side. The first lens group includes a first lens disposed at a position closest to the enlargement side, a second lens disposed at the reduction side of the first lens, and a plurality of positive lenses disposed at the reduction side of the second lens and each having positive power. The portion at the reduction side of a reduction-side lens that forms the second lens group and is located at a position closest to the reduction side is a telecentric portion. The projection system satisfies Conditional Expressions (1) and (2) below, Ln?gF?0.

Abstract: A projection system includes a first lens group having positive power, an aperture stop, and a second lens group having positive power sequentially arranged from the enlargement side toward the reduction side. The portion at the reduction side of a reduction-side lens that forms the second lens group and is located at a position closest to the reduction side is a telecentric portion. The projection system satisfies Conditional Expressions (1) and (2) below, ?>40°??(1) YL1/YIM<6.0 ??(2) where ? represents a maximum half angle of view of the overall projection system, YIM represents the distance from an optical axis to the largest image height of the projection image formed at an image formation device, and YL1 is the distance from the optical axis to a chief beam corresponding to the maximum image height in an imaginary plane.

Abstract: A projection system includes a first lens group, an aperture diaphragm, and a second lens group. A reduction side of the second lens group is telecentric. The first lens group includes a first sub-lens group having negative power and a second sub-lens group having positive power. Between a lens located at the most reduction side of the first sub-lens group and a lens located at the most enlargement side of the second sub-lens group, an air gap wider than air gaps between the other lenses adjacent to each other is provided. A lens located at the most reduction side in the first lens group is a positive lens. A cemented lens of the second lens group includes a first lens having negative power, a second lens having positive power, and a third lens having negative power from an enlargement side toward a reduction side. ?>40.

Abstract: An imaging lens includes a first lens having positive refractive power; a second lens having negative refractive power; a third lens having negative refractive power; a fourth lens having negative refractive power; a fifth lens; a sixth lens; a seventh lens; an eighth lens; and a ninth lens having negative refractive power, arranged in this order from an object side to an image plane side. The ninth lens is formed in a shape so that a surface thereof on the image plane side has an aspherical shape having an inflection point.

Abstract: There is provided a compact imaging lens configured to properly correct aberrations. The imaging lens includes, in order from an object side to an image side, a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, a third lens L3 with positive refractive power, a fourth lens L4 with negative refractive power, a fifth lens L5, a sixth lens L6, a seventh lens L7 with positive refractive power, and an eighth lens L8 with negative refractive power. The fourth lens is formed in a shape of a meniscus lens having an object-side surface being concave in a paraxial region. The eighth lens L8 has an aspheric image-side surface having at least one inflection point. Furthermore, the following conditional expression is satisfied: 0.04<D34/f<0.15 where f: a focal length of the overall optical system of the imaging lens, and D34: a distance along the optical axis between the third lens and the fourth lens.

Abstract: There is provided a compact imaging lens configured to properly correct aberrations. The imaging lens includes, in order from an object side to an image side, a first lens L1 having negative refractive power, a second lens L2 having negative refractive power, a third lens L3 having positive refractive power, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, and an eighth lens L8 having negative refractive power. The eighth lens L8 has an aspheric image-side surface having at least one inflection point.

Abstract: There is provided a compact imaging lens configured to properly correct aberrations. The imaging lens includes, in order from an object side to an image side, a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, a third lens L3 with positive refractive power, a fourth lens L4 with negative refractive power, a fifth lens L5, a sixth lens L6, a seventh lens L7 with positive refractive power, and an eighth lens L8 with negative refractive power. The fourth lens is formed in a shape of a meniscus lens having an object-side surface being concave in a paraxial region. The eighth lens L8 has an aspheric image-side surface having at least one inflection point. Furthermore, the following conditional expression is satisfied: 0.04<D34/f<0.15 where f: a focal length of the overall optical system of the imaging lens, and D34: a distance along the optical axis between the third lens and the fourth lens.