Abstract: An embodiment of an autofocus system is provided, including a height detection module, an image detection module, a movement unit and a processing unit. The height detection module is arranged to output a plurality of detection lights along a Z axis direction, wherein each of the detection lights has different focal lengths and different wavelengths such that the height detection module generates a dispersion region along the Z axis direction. The image detection module is arranged to capture an image of the focus position. The movement unit is arranged to move an object along the Z axis direction, wherein the object has an internal surface and an external surface. The processing unit determines whether the external surface and the internal surface are within the dispersion region according to the quantity of the energy peaks of a reflectance spectrum received by the height detection module.

Abstract: A exemplary method for determining vibration displacement in interferometric scanning, in which two optical signals having a phase difference with each other of a high-coherence interferogram corresponding to a tested surface is detected for determining a shifting displacement between the reference plane of interferometric apparatus and the tested surface. In one embodiment, a series of the shifting displacements with respect to a time interval are measured for determining the vibrating frequency of the tested surface by spectrum analysis. Meanwhile, an exemplary interferometric apparatus is also disclosed for calculating the relative position between the tested surface and the reference plane of interferometric apparatus whereby the interferometric apparatus is capable of compensating influences of vibration caused by the environment or the tested surface itself so as to obtain the surface profile and vibration frequency of the tested surface.

Abstract: The present disclosure provides a method and system for focusing, which modulates a broadband light into a dispersive light having a higher dispersion characteristic and a lower dispersion characteristic, and the dispersion light is projected onto an object so as to form an object light. By means of the filtering and dividing procedure, a first optical spectrum of the dispersion light with respect to the higher dispersion characteristic is utilized to detect a height information of the surface profile of the object. Then, according to the height information, a second optical spectrum of the dispersion light with respect to the lower dispersion characteristic is adjusted to focus onto the object so that an imaging sensing device is capable of sensing the object light with respect to the lower dispersion characteristic, and thereby obtaining a clear and focusing image corresponding to the surface of the object.

Abstract: A method and apparatus for simultaneously acquiring interferograms created with a plurality of different interference conditions are provided in the present invention. In the present invention, an object beam and a reference beam are used to interfere with each other and there are a plurality of sub-fields of interference simultaneously generated. All the sub-fields of interference can be simultaneously acquired by an image acquiring device with single shooting action so as to form the plurality of interferograms. Moreover, the present invention also provides a method for solving the phase information of the object beam from the interferograms formed by the foregoing said method.

Abstract: A exemplary method for determining vibration displacement in interferometric scanning, in which two optical signals having a phase difference with each other of a high-coherence interferogram corresponding to a tested surface is detected for determining a shifting displacement between the reference plane of interferometric apparatus and the tested surface. In one embodiment, a series of the shifting displacements with respect to a time interval are measured for determining the vibrating frequency of the tested surface by spectrum analysis. Meanwhile, an exemplary interferometric apparatus is also disclosed for calculating the relative position between the tested surface and the reference plane of interferometric apparatus whereby the interferometric apparatus is capable of compensating influences of vibration caused by the environment or the tested surface itself so as to obtain the surface profile and vibration frequency of the tested surface.

Abstract: A method and apparatus for simultaneously acquiring interferograms created with a plurality of different interference conditions are provided in the present invention. In the present invention, an object beam and a reference beam are used to interfere with each other and there are a plurality of sub-fields of interference simultaneously generated. All the sub-fields of interference can be simultaneously acquired by an image acquiring device with single shooting action so as to form the plurality of interferograms. Moreover, the present invention also provides a method for solving the phase information of the object beam from the interferograms formed by the foregoing said method.