Abstract: A workpiece surface defect detection device or the like that is capable of stably detecting a small surface defect with high accuracy is provided. A plurality of images indicating a portion to be measured of a workpiece serving as a target of detection of a surface defect is obtained in a state where a bright-and-dark pattern of an illumination device is moved relative to the workpiece, and a tentative defect candidate is extracted. When among a plurality of images from which the tentative defect candidate has been extracted, the number of images including the tentative defect candidate is greater than or equal to a threshold that has been set in advance, the tentative defect candidate is determined as a defect candidate. A plurality of images including the determined defect candidate is combined to generate a composite image, and a defect is detected on the basis of the generated composite image.

Abstract: According to a surface defect inspection device and a surface defect inspection method according to the present invention, an inspection face of an inspection object is irradiated with illumination light, and a defect at the inspection face is detected, based on an image including the inspection face captured. According to the surface defect inspection device and the surface defect inspection method, the illumination light is emitted with formation of at least one set of a light region and a dark region, and a range of a defect detection image region for the detection of the defect, to be set to the image capturing the inspection face irradiated with the illumination light in the light region, is adjusted in accordance with a previously defined degree of visibility for orange peel, at the detection of the defect at the inspection face.

Abstract: According to a surface defect inspection device and a surface defect inspection method according to the present invention, an inspection face of an inspection object is irradiated with illumination light, and a defect at the inspection face is detected, based on an image including the inspection face captured. According to the surface defect inspection device and the surface defect inspection method, the illumination light is emitted with formation of at least one set of a light region and a dark region, and a range of a defect detection image region for the detection of the defect, to be set to the image capturing the inspection face irradiated with the illumination light in the light region, is adjusted in accordance with a previously defined degree of visibility for orange peel, at the detection of the defect at the inspection face.

Abstract: Provided is an image pickup lens that forms an image on an image pickup element with light from a subject. In the image pickup lens, a lens that is disposed on an image pickup element side is fixed in position, and a focusing lens group having a plurality of lenses including a lens closest to the subject is moved in an optical axis direction, thereby performing focusing.

Abstract: Provided is a single-focus optical system which is configured, in order from the object side to the image side, of a first to third lens groups and in which the first lens group and the third lens group are fixed with respect to a predetermined imaging surface, and the second lens group is moved in the optical axis direction to focus, wherein the first lens group comprises at least one positive lens and at least one negative lens, the second lens group comprises at least one positive lens, the third lens group comprises at least one lens having at least one aspheric surface and having a positive optical power at a peripheral portion thereof and 5<|?v1|<70 is satisfied where ?v1 is a maximum value of the Abbe number difference between the positive lens and the negative lens in the first lens group.

Abstract: Provided is an image pickup lens that forms an image on an image pickup element with light from a subject. In the image pickup lens, a lens that is disposed on an image pickup element side is fixed in position, and a focusing lens group having a plurality of lenses including a lens closest to the subject is moved in an optical axis direction, thereby performing focusing.

Abstract: Provided is a single-focus optical system which is configured, in order from the object side to the image side, of a first to third lens groups and in which the first lens group and the third lens group are fixed with respect to a predetermined imaging surface, and the second lens group is moved in the optical axis direction to focus, wherein the first lens group comprises at least one positive lens and at least one negative lens, the second lens group comprises at least one positive lens, the third lens group comprises at least one lens having at least one aspheric surface and having a positive optical power at a peripheral portion thereof, and 5<|?v1|<70 is satisfied where ?v1 is a maximum value of the Abbe number difference between the positive lens and the negative lens in the first lens group.