A method of joining a razor blade to a blade support to form a razor blade assembly, the method including: directing a laser beam having an adjustable power output at an upper surface of the razor blade; and while advancing the laser beam along the razor blade: a) applying the laser beam at a first power output to the razor blade; b) reducing the first power output of the laser beam to a second power output; and c) applying the laser beam at the second power output to the razor to form a weld area joining the razor blade to the blade support. The weld area may be elongated and may include (i) a ratio of depth:width that is greater than about 2:1, and/or (ii) a ratio of length:width that is greater than about 5:1.

An image lens assembly system includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element and a seventh lens element. The first lens element with negative refractive power has a convex object-side surface. The second lens element has positive refractive power. The third lens element has refractive power. The fourth lens element has refractive power. The fifth lens element has refractive power. The sixth lens element with refractive power is made of plastic material, wherein at least one surface of the sixth lens element is aspheric. The seventh lens element with refractive power made of plastic material has a concave image-side surface changing from concave in a paraxial region to convex in a peripheral region, and at least one surface thereof is aspheric.

A displacement meter for suppressing errors occurring in sub-pixel estimation, comprising: alight source that illuminates an object; an image pickup unit for receiving diffused-reflected light from the object; and a calculation unit for calculating the a displacement amount of the object by using sub-pixel estimation and the cross-correlation function between reference image data and measurement image data, wherein an image acquired during a predetermined timing from the imaging unit serves as the reference image data and an image acquired during the next timing serves as the measurement image data, generates a correction displacement amount by subtracting a correction value from the displacement amount, sets the most recent measurement image data as the reference image data and sets a predetermined initial value as the correction value if the displacement amount meets a predetermined condition, and else sets the displacement amount obtained most recently as the correction value.

A displacement meter for suppressing errors occurring in sub-pixel estimation, comprising: alight source that illuminates an object; an image pickup unit for receiving diffused-reflected light from the object; and a calculation unit for calculating the a displacement amount of the object by using sub-pixel estimation and the cross-correlation function between reference image data and measurement image data, wherein an image acquired during a predetermined timing from the imaging unit serves as the reference image data and an image acquired during the next timing serves as the measurement image data, generates a correction displacement amount by subtracting a correction value from the displacement amount, sets the most recent measurement image data as the reference image data and sets a predetermined initial value as the correction value if the displacement amount meets a predetermined condition, and else sets the displacement amount obtained most recently as the correction value.

A compact folded projection system is described that includes a laser light source, a folded lens system comprising a lens stack including two or more refractive lenses and a light folding element (e.g., a prism), and a diffractive beam splitter that includes at least one diffractive surface. The light folding element provides a “folded” optical axis for the lens system to reduce the Z-height of the projection system, for example to within a range of 1.7 to 4 millimeters (e.g., 2 millimeters in some implementations). The laser light source emits light that is refracted by the lens stack to the folding element. The folding element redirects the light to the beam splitter which replicates the light into N×M duplications or tiles to thus generate a larger field of view (FOV) than the internal FOV of the lens system.

Systems and methods are disclosed for performing ophthalmic optical coherence tomography with multiple resolutions. In some embodiments, a system comprises a light source, an output lens, and a set of optical components between the light source and the output lens, the set of optical components comprising an afocal zoom telescope. The set of optical components is adapted to provide imaging both at a first field of view with a first resolution and at a second field of view with a second resolution, wherein the first field of view is wider than the second field of view and the second resolution is higher than the first resolution. A method of performing ophthalmic optical coherence tomography with multiple resolutions may be performed using one or more of the systems described herein.

Systems and methods are disclosed for performing ophthalmic optical coherence tomography with multiple resolutions. In some embodiments, a system comprises a light source, an output lens, and a set of optical components between the light source and the output lens, the set of optical components comprising an afocal zoom telescope. The set of optical components is adapted to provide imaging both at a first field of view with a first resolution and at a second field of view with a second resolution, wherein the first field of view is wider than the second field of view and the second resolution is higher than the first resolution. A method of performing ophthalmic optical coherence tomography with multiple resolutions may be performed using one or more of the systems described herein.

An image projection apparatus includes: a light source; an image display element including multiple micromirrors arranged in two dimensions, the multiple micromirrors forming an image display plane, each micromirror having a reflecting surface; and a projection optical system. Conditional expressions (1) and (2) below are satisfied:
θ1≥14(deg)  (1)
1.2<BF/L<2.2  (2) where θ1 is a maximum tilt angle of the reflecting surface of each micromirror with respect to the image display plane, L is a diagonal length of the image display plane, and BF is a distance between a vertex of a lens within the projection optical system and closest to the image display plane and the image display plane along an optical axis of the projection optical system.

An image projection apparatus includes: a light source; an image display element including multiple micromirrors arranged in two dimensions, the multiple micromirrors forming an image display plane, each micromirror having a reflecting surface; and a projection optical system. Conditional expressions (1) and (2) below are satisfied:
θ1≥14(deg)  (1)
1.2<BF/L<2.2  (2) where θ1 is a maximum tilt angle of the reflecting surface of each micromirror with respect to the image display plane, L is a diagonal length of the image display plane, and BF is a distance between a vertex of a lens within the projection optical system and closest to the image display plane and the image display plane along an optical axis of the projection optical system.

The imaging optical system consists of a first optical system and a second optical system in order from a magnified side. The second optical system forms an image on an image display surface as an intermediate image, and the first optical system forms the intermediate image on a magnified-side conjugate plane. A height of a principal ray of light having a maximum angle of view becomes maximum on a lens surface of the whole system on the most magnified side, among heights of principal rays of light having a maximum angle of view on respective lens surfaces. The imaging optical system satisfies predetermined conditional expressions.