Novel approach to optical profiler with gradient focal point methods

Abstract

Novel gradient focal point (GFP) methods by use of the gradient curvature cylindrical lens, the gradient thickness cylindrical lens and a tilted imaging sensor are proposed for the optical profiler. With the employed simple idea that the different divergence angle of an input beam to the lens generates the different focal position, the height information of one point can be obtained just in a single-shot by GFP approaches. The feasibility of the proposed system is demonstrated to be an alternative to optical profilers.

Chromatic confocal microscopy with a novel wavelength detection method using transmittance

“…Equation (1) implies that the wavelength of the incident light is also a function of the transmittance when the incident light has a narrow band under the assumption that the function is one-to-one. Since the transmittance can be measured by the PMTs, which have a very high frequency response up to hundreds of Megahertz, the detection speed of the peak wavelength can be significantly increased compared to linear-array based spectrometers.…”

“…The demand for fast three-dimensional (3D) microscopy has been growing in many industrial fields, including the manufacturing process of semiconductors and flat panel displays [1]. Optical methods enable non-destructive and non-contact 3D surface profiling with highresolution and high-speed [2].…”

Multipoint scanning dual‐detection confocal microscopy for fast 3D volumetric measurement

“…Accurate surface measurement of three‐dimensional (3D) objects is necessary for many industrial fields, and high speed imaging is also a key factor in mass‐production inspection equipment (Leach, ). Various 3D surface measurement optical systems have been developed, including phase‐shifting interferometry, white light scanning interferometry, and confocal scanning microscopy (CSM), techniques that have the advantages of being nondestructive and noncontact processes (Kim et al ., ; Leeghim et al ., ). However, each technique makes compromises between its resolution, field of view (FOV), and imaging speed.…”

High-speed 3-D measurement with a large field of view based on direct-view confocal microscope with an electrically tunable lens

“…The demand for accurately measuring the 3-dimensional (3-D) shape of various objects has been existing in many industrial and medical fields. Especially, the fast measurement technology of large-area and micro-surface is required in the inspection process of semiconductors, flat panel or plasma displays, and microelectromechanical systems [1][2][3]. In addition, large depth scanning range is needed in dental CAD/CAM industry [4].…”