A laser processing apparatus includes a laser light output section, a laser light scanning section, a distance measurement light emitting section which emits distance measurement light, a pair of light receiving elements which receives the distance measurement light emitted from the distance measurement light emitting section and reflected by the workpiece, optical axes of the pair of light receiving elements being arranged inside the housing so as to sandwich an optical axis of the distance measurement light emitting section, a distance measuring section which measures a distance to the surface of the workpiece, and a light receiving lens which is arranged such that each of the optical axes of the pair of light receiving elements passes through the light receiving lens, and condenses the distance measurement light that has been reflected by the workpiece on respective light receiving surfaces of the pair of light receiving elements.

A laser processing apparatus includes a laser light output section, a laser light scanning section, a distance measurement light emitting section which emits distance measurement light, a pair of light receiving elements which receives the distance measurement light emitted from the distance measurement light emitting section and reflected by the workpiece, optical axes of the pair of light receiving elements being arranged inside the housing so as to sandwich an optical axis of the distance measurement light emitting section, a distance measuring section which measures a distance to the surface of the workpiece, and a light receiving lens which is arranged such that each of the optical axes of the pair of light receiving elements passes through the light receiving lens, and condenses the distance measurement light that has been reflected by the workpiece on respective light receiving surfaces of the pair of light receiving elements.

A laser processing apparatus includes a laser light output section, a first scanner and a second scanner, a distance measurement light emitting section, a reference member which is arranged at a position which is the other end of a correction optical path formed with the distance measurement light emitting section as one end of the correction optical path and is arranged such that an optical path length of the correction optical path is a predetermined reference distance, a distance measurement light receiving section which receives distance measurement light reflected by the workpiece or the reference member, a distance measuring section which measures a distance to the workpiece or the reference member, and a distance correcting section which compares a measurement result of the distance to the reference member with the reference distance stored in advance to correct the measurement result obtained by the distance measuring section.

A laser processing apparatus includes a laser light output section, a first scanner and a second scanner, a distance measurement light emitting section, a reference member which is arranged at a position which is the other end of a correction optical path formed with the distance measurement light emitting section as one end of the correction optical path and is arranged such that an optical path length of the correction optical path is a predetermined reference distance, a distance measurement light receiving section which receives distance measurement light reflected by the workpiece or the reference member, a distance measuring section which measures a distance to the workpiece or the reference member, and a distance correcting section which compares a measurement result of the distance to the reference member with the reference distance stored in advance to correct the measurement result obtained by the distance measuring section.

The invention relates to an optical device, comprising: a lens having an adjustable focal length. According to the invention, a light source which is configured to emit light that is affected by said lens and impinges on at least a first photosensitive element, which is designed to generate a first output signal corresponding to the intensity of light impinging on it, wherein the first photosensitive element is configured to measure only a portion of the intensity distribution of said emitted light, and wherein the light source, the lens and the first photosensitive element are configured such that a change of the focal length of said lens changes the intensity distribution of the emitted light that impinges on the first photosensitive element, so that each focal length of the lens is associated to a specific first output signal generated by the first photosensitive element.

The invention relates to an optical device, comprising: a lens having an adjustable focal length. According to the invention, a light source which is configured to emit light that is affected by said lens and impinges on at least a first photosensitive element, which is designed to generate a first output signal corresponding to the intensity of light impinging on it, wherein the first photosensitive element is configured to measure only a portion of the intensity distribution of said emitted light, and wherein the light source, the lens and the first photosensitive element are configured such that a change of the focal length of said lens changes the intensity distribution of the emitted light that impinges on the first photosensitive element, so that each focal length of the lens is associated to a specific first output signal generated by the first photosensitive element.

According to an embodiments, a lens assembly or an electronic device including the same may include: a first lens having positive refractive power; a second lens having positive refractive power; a third lens having positive or negative refractive power; and a fourth lens having positive or negative refractive power. The first lens, the second lens, the third lens, and the fourth lens may be sequentially arranged from a subject to an image sensor along an optical axis, and the sum of Abbe numbers of the first lens, the second lens, the third lens, and the fourth lens may satisfy Conditional Expression 1 as follows. 201+2+3+4125 where 1, 2, 3, and 4 represent the Abbe numbers of the first through fourth lenses, respectively.

Provided is an imaging technique capable of detecting a focus even in an imaging apparatus of a speckle image. The imaging apparatus includes a coherent light source that irradiates an imaging object with coherent light, an incoherent light source that irradiates the imaging object with incoherent light, a speckle imaging unit that captures a speckle image obtained from scattered light of the imaging object irradiated with the coherent light, a non-speckle imaging unit that captures a non-speckle image obtained from reflected light of the imaging object irradiated with the incoherent light, and a focus detection unit that detects a focus of the speckle imaging unit on the basis of a focal position of the non-speckle imaging unit.

Provided is an imaging technique capable of detecting a focus even in an imaging apparatus of a speckle image. The imaging apparatus includes a coherent light source that irradiates an imaging object with coherent light, an incoherent light source that irradiates the imaging object with incoherent light, a speckle imaging unit that captures a speckle image obtained from scattered light of the imaging object irradiated with the coherent light, a non-speckle imaging unit that captures a non-speckle image obtained from reflected light of the imaging object irradiated with the incoherent light, and a focus detection unit that detects a focus of the speckle imaging unit on the basis of a focal position of the non-speckle imaging unit.

To determine a position of an object (100) parallel to the optical axis (120) of an optical device (1), the object (100) is illumined from a first illumination direction (210-1) and from a second illumination direction (210-2) and an image (230-1, 230-2) is acquired in each case. The position of the object (100) is determined based on a distance (250) between imaging locations of the object (220-1, 220-2) in the images (230-1, 230-2).