Abstract: Embodiments relate to a free space optical (FSO) communication terminal. The terminal includes an optical source and optics. The optical source can produce optical beams at different wavelengths. The optics direct optical beams in a direction towards a remote FSO communication terminal. A wavelength dependence of the optics results in a divergence of the optical beam that depends on a wavelength of the optical beam. A controller may control the wavelength of the optical beam produced by the optical source, thereby adjusting the divergence of the optical beam (e.g., according to an acquisition process or a tracking process).

Abstract: A characteristic of a surface is measured by illuminating the surface with optical radiation over a wide angle and receiving radiation reflected from the surface over an angle that depends on the extend of the illumination angle. An emissivity measurement is made for the surface, and, alternatively, if a reflectivity measurement is made, it becomes more accurate. One application is to measure the thickness of a layer or layers, either a layer made of transparent material or a metal layer. A one or multiple wavelength technique allow very precise measurements of layer thickness. Noise from ambient radiation is minimized by modulating the radiation source at a frequency where such noise is a minimum or non-existent. The measurements may be made during processing of the surface in order to allow precise control of processing semiconductor wafers, flat panel displays, or other articles. A principal application is in situ monitoring of film thickness reduction by chemical-mechanical-polishing (CMP).

Abstract: In the beam path of an Optical Cross Connect between the front face of a fiber block and a moveable mirror array are placed a telecentric lens and multi-surface optical element. The lens is placed adjacent the front face with a front focal plane coinciding with the front face. The substantially parallel beam path axes between the front face and the telecentric lens are converted by the lens into dispersing directions towards the optical element. Discrete optical surfaces of the optical element redirect the dispersing beam paths in a fashion such that the beam paths coincide in the following with corresponding moveable mirrors of a mirror array. Pitches of arrayed fiber ends and of the optical surfaces as well as the moveable mirrors are independently selectable. The telecentric lens simultaneously focuses the signal beams with improved beam separation and reduced signal loss.

Abstract: In the beam path of an Optical Cross Connect between the front face of a fiber block and a moveable mirror array are placed a telecentric lens and multi-surface optical element. The lens is placed adjacent the front face with a front focal plane coinciding with the front face. The substantially parallel beam path axes between the front face and the telecentric lens are converted by the lens into dispersing directions towards the optical element. Discrete optical surfaces of the optical element redirect the dispersing beam paths in a fashion such that the beam paths coincide in the following with corresponding moveable mirrors of a mirror array. Pitches of arrayed fiber ends and of the optical surfaces as well as the moveable mirrors are independently selectable. The telecentric lens simultaneously focuses the signal beams with improved beam separation and reduced signal loss.

Abstract: A characteristic of a surface is measured by illuminating the surface with optical radiation over a wide angle and receiving radiation reflected from the surface over an angle that depends on the extend of the illumination angle. An emissivity measurement is made for the surface, and, alternatively, if a reflectivity measurement is made, it becomes more accurate. One application is to measure the thickness of a layer or layers, either a layer made of transparent material or a metal layer. A one or multiple wavelength technique allow very precise measurements of layer thickness. Noise from ambient radiation is minimized by modulating the radiation source at a frequency where such noise is a minimum or non-existent. The measurements may be made during processing of the surface in order to allow precise control of processing semiconductor wafers, flat panel displays, or other articles. A principal application is in situ monitoring of film thickness reduction by chemical-mechanical-polishing (CMP).

Abstract: In the beam path of an Optical Cross Connect between the front face of a fiber block and a moveable mirror array are placed a telecentric lens and multi-surface optical element. The lens is placed adjacent the front face with a front focal plane coinciding with the front face. The substantially parallel beam path axes between the front face and the telecentric lens are converted by the lens into dispersing directions towards the optical element. Discrete optical surfaces of the optical element redirect the dispersing beam paths in a fashion such that the beam paths coincide in the following with corresponding moveable mirrors of a mirror array. Pitches of arrayed fiber ends and of the optical surfaces as well as the moveable mirrors are independently selectable. The telecentric lens simultaneously focuses the signal beams with improved beam separation and reduced signal loss.

Abstract: A characteristic of a surface is measured by illuminating the surface with optical radiation over a wide angle and receiving radiation reflected from the surface over an angle that depends on the extend of the illumination angle. An emissivity measurement is made for the surface, and, alternatively, if a reflectivity measurement is made, it becomes more accurate. One application is to measure the thickness of a layer or layers, either a layer made of transparent material or a metal layer. A one or multiple wavelength technique allow very precise measurements of layer thickness. Noise from ambient radiation is minimized by modulating the radiation source at a frequency where such noise is a minimum or non-existent. The measurements may be made during processing of the surface in order to allow precise control of processing semiconductor wafers, flat panel displays, or other articles. A principal application is in situ monitoring of film thickness reduction by chemical-mechanical-polishing (CMP).

Abstract: An instrument for determining spectral content of an input light. The instrument has a rotating optical element that separates an input light into two partial beams and thereby introduces a variable OPD between the partial beams. The instrument then records an interferogram as a function of the variable OPD and thereby Fourier or Fast Fourier transforms the interferogram into a spectrogram so that the spectral content of the input light is revealed.