32 results about "Wavefront curvature" patented technology

An image display device for optically displaying an image is disclosed. This device includes: a light source; an imaging-light generator converting light emitted from the light source, into imaging light representative of the image to be displayed, to thereby generate the imaging light; a relay optical system focusing the imaging light emitted from the imaging-light generator, on an image plane which is located at an optically conjugate position to the imaging-light generator, the relay optical system defining a pupil through which the imaging light passes, within the relay optical system; a variable-focus lens disposed at a position generally coincident with the pupil, the variable-focus lens having a varying focal length; and a wavefront-curvature adjuster configured to vary the focal length by operating the variable-focus lens, to thereby adjust a wavefront curvature of the imaging light emitted from the relay optical system.

An optical scanning device having: a light source for emitting a light beam; a deflector having a plurality of flat reflecting surfaces; a first optical system disposed between the light source and the deflector; and a second optical system disposed between the deflector and a photoreceptor surface, and configured such that the reflecting surfaces of the deflector and the photoreceptor surface are conjugated in a sub-scanning direction at every deflection angle in a main-scanning range. In the optical scanning device, the light beam traveling from the first optical system to the deflector has a width greater than a dimension in a main-scanning direction of each reflecting surface of the deflector, and the light beam passes through different portions of the first optical system depending on whether the light beam is to be deflected by the deflector to be directed to an edge portion of the main-scanning range or to be directed to a center portion of the main-scanning range such that the light beam traveling to the deflector has a smaller average wavefront curvature in a sub-scanning direction when the light beam is to be deflected by the deflector to be directed to an edge portion of the main-scanning range than when the light beam is to be deflected by the deflector to be directed to the center portion of the main-scanning range.

The invention provides a method for optimizing the stacking parameters of a seismic common reflection surface, which includes the following steps: S1, acquiring seismic data, and acquiring the wavefront curvature radius of an initial reflection point and the wavefront curvature radius and inclination angle of an initial reflection surface based on the seismic data; and S2, acquiring the optimal values of the wavefront curvature radius of the initial reflection point and the wavefront curvature radius and inclination angle of the initial reflection surface according to the wavefront curvature radius of the initial reflection point and the wavefront curvature radius and inclination angle of the initial reflection surface and based on an objective function. The invention provides a method foroptimizing the stacking parameters of a seismic common reflection surface. In the first step, three initial parameters are found, the initial parameters are searched one by one, and simple linear search can be used. In the second step, an optimal combination solution is searched near the initial parameters by using a global optimization algorithm. Thus, the problem on how to fast scan the CRS imaging parameters by a CMAES algorithm is solved.

The invention discloses a method for measuring focal length and equivalent f-number with a grating type wavefront curvature sensor. In the method, a defocused wavefront with the focal length to be measured is generated by transmission or reflection, and the defocused wavefront is incident into the grating type wavefront curvature sensor, and the grating type wavefront curvature sensor is used to detect the defocused light spots on the two defocused surfaces , measure the diameter d1 of the front defocused spot and the back defocused spot d2, and obtain the equivalent focal length fg of the defocus grating and the focal length fi of the short focal length lens according to the design parameters of the grating wavefront curvature sensor; ③. Calculate the diameter d1 of the two defocused spots The normalized difference S between d2 and d2; ④. Determine the positional relationship of the obtained two defocused light spots, and calculate the focal length or equivalent f-number through different formulas. The invention has the advantages of high measurement accuracy, wide application range, low cost and the like.