Abstract: The rate of increasing storage capacity is being slowed by the inability to produce ever
closer flying heights between the sliders and disks. In order to allow the sliders to ‘fly’ faster and
more closely to the disk surfaces, it is important to control the surface of substrates of hard disks to
a super-smooth level. However, there are no sophisticated instruments and assessment standards
for super-smooth surfaces. In this research, the authors attempt to build a measurement and
assessment protocol for the evaluation of super-smooth surfaces using a white-light optical
instrument CCI (Coherence Correlation Interferometer). The key advantage of this instrument is its
exceptionally high vertical resolution which is an order of magnitude better than comparable
systems. This paper focuses on discussing the factors influencing the experimental results; they
include sampling intervals, the number of measurements, scan size, filter cut-off wavelength etc.
Based on the experimental results, an optimum protocol for measurement and assessment are
recommended, and then the authors measure and compare the surface roughness of six hard disks
derived from differing chemical mechanical polishing (CMP) ‘abrasives’. It has been found that:
(1) the roughness values of the six hard disks surfaces have all reached a sub-nanometre level; (2)
CMP regimes have little influence on the topography of the hard disk surfaces.
Abstract: Based on the beam coherence-polarization (BCP) matrix approach and propagation law
of partially coherent beams, the propagation properties of partially polarized Gaussian Schell-model
(PGSM) beams through an aperture lens with spherical aberration were studied. Our main attention
was focused on the effect of spherical aberration of the lens, partial coherence, aperture diffraction
and polarization on the behavior of the irradiance. The numerical calculation results are given to
illustrate how these parameters affect the focusing properties. A comparison with the previous
publications is also made, showing some extension has been made in our work.
Abstract: The coupling of laser with fiber has been used for many fields: such as industry, medical
treatment, and communications. At the present time, the coupling methods are direct coupling and
lens coupling mainly. With the existence of a damage threshold in fiber end face and interior, it
very difficult to use the above ways to realize the coupling of high-power, high-energy and narrow
pulse laser with optical fiber. In this paper, a new method to reducing laser power density and
energy density in optical fiber end face and interior is presented and designed a hollow cone shaped
laser-fiber coupler by analyzing the mechanism of damage of optical fiber. When cylindrical Gauss
beam incident into the hollow cone coupler will form a light spot, the energy density is of quasiaverage
distribution. By using this coupler, we realized the coupling of a high-power (10MW),
energy (12mJ), narrow pulse (12ns) and electro-optical Q-switched Nd:YAG laser with the
multimode optical fiber (diameter is 600μm) and the coupling efficiency is 70%.
Abstract: This paper presents the inspection technology for a freeform surface component which is
named F-theta lens. F-theta lens is widely used in laser scanners, printers, etc. Freeform
characterization is one of the main approaches to verify the manufacturing precision of freeform
surface. At present, there is still a lack of techniques for the characterization of freeform surfaces.
This study aimed to explore some approaches to inspect freeform surfaces. Two types of
measurement methods, namely contact and non-contact measurement methods, are employed to
measure the F-theta lens surface. The pros and cons, the existing problems, different applications
and areas for improvement of the two methods are discussed. A series of advanced measuring
instruments are used in the measurement process. A brief description of measurement mechanisms
of these instruments is also presented. As a whole, this paper contributes to the development of the
precision measurement technology for optical freeform surfaces.
Abstract: In order to obtain competitiveness in the field of industrial manufacturing, a reduction in
the development period for the batch machining of products is required. It is essential to analyze the
stress distribution and deformations of machining system which is used for manufacturing the
aspheric lens using FEM software ANSYS. Finite element simulations have been performed in
order to study the influence of machining system which was developed in this study on structures. It
is very important to understand the structural behavior of machining system. This research
investigated the static analysis and dynamic analysis of machining system for aspheric lens to
predict the damage due to loading.
Abstract: This paper reports a novel micro extrinsic fiber-optic F-P interferometric (MEFPI) sensor
micromachined on a conventional optical fiber (Corning SMF-28) by using a near-infrared
femtosecond laser, for the first time to the best of our knowledge. The strain and temperature
characteristics of such a sensor were investigated and the experimental results show that the strain
and temperature sensitivities are 0.006nm/με and -0.0017nm/°C, respectively. This type of MEFPI
sensors has a number of advantages when compared with conventional EFPI sensors, such as easy
fabrication, high integration degree, good reliability, low temperature cross-sensitivity, low cost,
and capability for mass-production, offering great potential for a wide range of sensing applications.
Abstract: Aberrations of the human eyes in the horizontal visual field were measured with
modified Hartmann-Shack wave front sensor. The characteristic of third to tenth order Zernike
aberration rms both temporally and nasally out to 50° is as follows: considerable differences
occur among subjects in the pattern of aberrations, particularly for the dominating second-order
aberrations; the third to tenth order Zernike aberrations increase with the visual angle, but the
increscent magnitude decreases as the Zernike order increases; in despite of imperfect
symmetry, the increscent magnitude is the same on the whole; the third-order Zernike
aberrations increases up to 2 times from 0° to ±50° visual angle, the forth-order up to 1.8 times,
and the fifth to tenth order up to 1.7~1.3 times.
Abstract: This research aimed to develop a novel two-stage micro injection compression molding
(μ-ICM) process for fabrication of plastic diffractive optic elements (DOE). The DOE was designed
with the spherical coefficients and the Fresnel lens. A piezo actuator was installed inside the mold
plate for activating the mold insert for the second compression motion for micro ICM of the DOE
lens. The first experiment proceeded to find the operation window of Fresnel lens and then compare
the product weight of flat spherical lens by injection molding (IM), injection compression molding
(ICM) and μ-ICM. The second experiment was to investigate the effectiveness of micro
compression activated by the piezo actuator by the transfer ratio of grooves (TRG) of the DOE lens
with spherical lens and Fresnel lens. Results showed that the μ-ICM of the DOE can obtain the
highest TRG than that of IM and conventional ICM processes. Therefore, results of this research
can be explored to related aspheric optical elements with micro features, such as fine lens used in
the zoom lens of camera.
Abstract: Manufactured miniature parts conventional machine tools are substituted by mini-scale
manufacturing system called miniaturized machine tool (mMT). However, calibration of mMT is
extremely difficult due to its small dimensions. This paper presents a novel optical measuring
system to measure integrated geometric errors namely a) three translation errors and b) three
rotational errors. The squareness error between two moving axes was calculated by least-square
method. These 7-DOF geometric errors were acquired simultaneously in one setup for each motion
direction. The proposed measuring system consisted of two laser diodes, two beam splitters and
three 2D position sensing detectors (PSDs). Configuration of this measuring system was proved by
homogenous transformation matrix (HTM), and the relationship between PSD readings and
geometric errors calculated by the algorithm were derived according to the configuration.
Simulation were carried out to prove the validity of this algorithm. Sensitivity analysis based on
mounting errors of system components is also presented in this paper. It is useful for further
experiments in alignment of system components.