A new planar micro-lens has been fabricated by selectively diffusing a dopant into a planar substrate. First diffusion conditions have been investigated theoretically to make the planar micro-lens. Second the monomer exchange technique for plastics and the ion exchange technique for a glass substrate are applied for an initial trial. 2-D planar micro-lenses with 1.2mmφ and 9.4mm of the focal length have been arrayed in a glass substrate. Then, tthe feasibility of an electro-migration technique in making a planar micro-lens has been tested and it was confirmed that we can fabricate short focal length lenses in relatively short time.

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Optical waveguide bragg grating lenses are treated. Two-dimensional coupled-mode theory for a plane and a cylindrical guided wave in the lens is described. The coupling of two cylindrical guided waves is briefly mentioned. The lenses are fabricated by the technique of photolithography and electron lithography.

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The in-line holographic lens with high numerical aperture up to 0.55 was photochemically fabricated in the methylene-blue sensitized dichromated gelatin film by means of the specially designed optics and the carefully controlled process. The evaluation of the MTF, the focused beam profile and the diffraction efficiency was performed. Bragg and Raman-Nath diffractions occurred in the hologram were also investigated. We developed the new optical head employing the above lens and the optical disk player equipped with this head and succeeded in playing back the video and PCM audio signals with the good signal-to-noise ratio.

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This paper describes two novel electrooptic devices based on an one-dimensional Fresnel lens consisting of Ti-diffused channel waveguides on a LiNbO₃ crystal. One is a Fresnel light modulator (FLM) by which the main lobe of diffraction pattern near the focal point is modulated with an applied voltage while focusing is almost kept. The basic parameters of the FLM with 13 zones at 633nm are: the focal length (f) is 12.413mm, the full width of beam at half power (W) 56μm, thehalf-wave voltage 28V, the extinction ratio 18.1dB and the insersion loss 10.1dB.
The other is a Fresnel light scanner (FLS) by which the main lobe of diffraction pattem in the focal plane is continuously scanned as a function of voltage. The experimental results of the FLS with 20 zones at 633nm are as follows: fis 2.5cm, Wis 16-20μm and the num ber of resolvable spots following the Rayleigh resolution criterion is 2.2.
The FLM is apPlicable to a diffraction limited aberration-free lens and high optical power modulator. The FLS has attractive functions such as lensless light scanning and linear light modulation.

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An automatic method of designing grating instruments equipped with aberration-corrected gratings has been developed. The optimization was made of the light path function in nonexpanded form, instead of the expanded path function in conventional methods, over a given range of wavelength for given ruled area and entrance-slit height. The method was applied to the design of a Seya-Namioka monochromator and was compared with conventional ones. The present method seems to be effective especially for grazing incidence spectrometers, spectrometers with a small F-number, and as such.

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Design and production of holographic gratings for grazing incidence spectrographs for use in the 5-200A region are described. The image plane of the spectrograph is flat over the distance of about 30mm so that multichannel real time photo-electric detection is possible with an array detector. A toroidal grating is adopted to avoid the light loss due to astigmatism, and its blank surface is tested with a modified point diffraction interferometer. The grating is recorded in Shipley AZ-1350 photoresist with an argon ion laser, and is coasted with gold after the development.

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The characteristics of a monochromatic, coherent light beam, of Gaussian radial intensity variation, as it propagates along the axis of an optical system, has been well-known. But the design of the optical system, which collimates the laser beam as narrow as possible over a predeterminate measuring interval, has been hardly discussed so far. By introducing a simple evaluation function on the beam width, it becomes possible to design the optical system which gives the narrowest beam over the measuring interval. The feature of this design lies on the fact that the beam width which is given by the optimized optical system depends only on the length of measuring interval and the wavelength of light. Some numerical examples are also presented.

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We have introduced, since 1978, a world famous lens design program ACCOS V developed by Scientific Calculations, Inc. in U.S.A. for our time-sharing service and closely observed its superior applicability through assisting our many users in their various works. We, therefore, summarized the outstanding characteristics of this program based on our experience, specifically referred to macro function, optimization and handing of assymmetrical system.

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70-150mm F/2.8 zoom lens capable of producing soft-focus effects with spherical aberrations both under-corrected or over-corrected while providing high performance in normal mode has been developed. Researches are made on defused soft-focus effects both in the background and foreground and as to what physical qualities a lens should have as a zoom lens giving attractive soft-focus effects as well as high performance in normal mode.

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This paper presents the novel electronic focus-state detecting system. It is described not only basic principle of the focusing system but also the designed example, i. e. zoom lens for the use of color TV camera.
And it is added some numerical discussions on the focusing detectivity of the designed example.

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A new method of measuring the radii of wavefront curvature of laser beams is presented and verified by experiments. Its principle is that the sensitivity of speckle displacement for in-plane translation of diffuse objects depends on the curvature of the incident wavefront. The speckle displacement is measured by an electronic speckle correlation technique using a linear image sensor and a microcomputer.

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Two types of testing methods of accurate optical flats are proposed and experimentally examined. They are developed in connection with the Fabry-Perot etalon which is used as the monochrometer in Brillouin scattering experiment. The parallelism and the relative flatness of an etalon are defined so that they are independent quantlties each other. The first method proposed is the photographic testing one with a multilens and it is shown that this system can determine the relative flatness to an accuracy of aboutλ/1000. The second is the pressure scanning and photoelectric detection method with a multilens and it is shown that the accuracy obtained by this system is higher than the accuracy obtained by the photographic method.

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The use of fringe patterns is very powerful in extracting quantitative information, but sometimes extremely tedious and time consuming to evaluate quantitative data. This paper describes two types of interactive semi-automatic fringe analysis systems, and also describes the fringe scanning method of analyzing interferometric fringes with sufficient tilt introduced. One of the semi-automatic systems is based on a technique of fringe peak tracing, in which computer programs of preprocessing for noise reduction, fringe skeletoning and thinning, and interactive fringe order determination. Alternative is the one-dimensional version of fringe analysis. Only several analysis lines are read in for fringe peak detection and fringe orders are determined interactively. Fringe orders between the analysis lines are interpolated. These two are semi-automatic because of the interactive fringe order determination process, while in the method of fringe scanning all the processes of fringe analysis can be automated. Interferometric fringes with sufficient tilt are multiplied by reference fringe patterns to remove the tilt term in a computer. Phase profiles of interferometric fringes are obtained by summing up fringes multiplied with weights synchronous to the phase of the reference fringe. Finally, some examples of fringe data evaluation are presented, including 3-D plots of fringe data in which tilt term is removed, a point spread function and an optical transfer function.

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A computer-based method of fringe pattern analysis is proposed with applications to topometry and interferometry. The method uses a noncontour-type fringe pattern which is processed in Fourier-spectrum domain to extract the necessary phase information separately from other unwanted amplitude variations. The method has advantages over the conventional contour-fringe methods in both accuracy and sensitivity, as well as in its capability of automatic distinction between elevation and depression of the object-or wavefront form.

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