Piezoelectric type dispenser

1

• One Drop Filling

• Piezoelectric type dispenser
• The principle is to actuate a disk type PZT to
  push the liquid and make the drop to perform a
  linearly stable ejection behavior.

• Glue dispenser
• The step motor applies a force to a valve that
  forces the valve toward the liquid container so
  as to open the opening. After opening the valve,
  the dispensing apparatus control the dropping
  amounts using the air pressure.

2

• One Drop Filling

• In situ volume measurement of micro droplets
• The system developed utilizes a stroboscopic
  technique to synchronize the triggering of a
  strobe light and a CCD camera. A steady image of
  the droplet flying in free space can be captured
  in situ by the CCD camera. The method of precise
  volume estimation is based on a rotationally
  symmetric model of the droplets shape.

Measured weights of 1000 drops by the subpixel
method
(a) A schematic diagram of a droplet flying in
free space (b), (c), (d) Image processing
3

• Development of chromatic confocal microscope

3-color LED
40X microscope

• The nominal dimension of the grating the pitch
  is 5.0 µm and the height is 2.5 µm.

Focus lens
Beam splitter
Color CCD
Beam splitter
60X microscope

• To get the RG-ratio via the depth response curve
  could determine the height of work piece.

4

• Monitoring System
• of Machine Tool Accuracy Degradation

• Introduction
• During machining, feed force, cutting force and
  the self weight of machine tool applied to the
  contact surface, such as the slide way and the
  linear slide, will cause friction and wear. For
  improper assembled parts, it will incur loose
  contact. The accuracy of machine tool will be
  degraded.
• This research is to develop a monitoring system
  of machine tool accuracy degradation. One object
  is to develop a software, under known cutting
  conditions, this software can predict the slider
  displacements, feed force, reaction force of
  contact surfaces and wear of slideways. Another
  to reconstruct the commercial DVD pick-up head to
  be a precision angular probe. It can measure
  three angular errors of working stage, and the
  angular errors can be real-time processed by
  embedded system, and then angular errors can be
  displayed on PC that user can know the machining
  condition. The advantages of this system are high
  precision, low cost and monitoring immediately,
  so that can improve industrys competitiveness.

5

• Monitoring System
• of Machine Tool Accuracy Degradation

Optical system of DVD pick-up head
Residual of angular calibration
6

• Monitoring System
• of Machine Tool Accuracy Degradation

The software of the machine tool accuracy
degradation
7

• Principle of the Focusing Probe

Disc
Voice coil motor
and arm springs
Objective lens
Collimator lens
Laser diode
Polarization beam splitter and ?/4 plate
FES curve
Grating
Cylindrical lens
Quadrant detector
Photodiode IC
10um
Basic structure of DVD pick-up head
Schematic representation of astigmatic
auto-focusing method
8

• Development of the DVD Laser Probe

9

• Measure the Profile of the Scraping Work Piece

DVD Laser Probe

• The micro meter scratches on the scraping work
  pieces can measure by the DVD probes Focus
  Error Signal can be find out.

Objective lens
Scraping work piece
Moving work plate
10

• The micro CMM

• Introduce
• Rectangular type of the bridge is always
  employed in the precision CMM structure for
  mounting the Z-axis probe. The deformation in the
  center of the bridge is very critical because of
  the concentrated load from the spindle. The
  research proposes a fixed pagoda structure. Under
  the same dimension and the same spindle load, the
  maximum deflection at the center of the bridge
  can be reduced Abbe free in all axes.

11

• 2-D high Precision Coplanar Stage

• Introduction
• Conventional XY stage is stacked up by two
  linear stages. The Abbe error of the lower stage
  is high. An innovation co-planar stage is thus
  proposed in this study.
• The stage motion is actuated by a ultrasonic
  motor, the opposite side set the motion sensor of
  LDGI.

12

• LDGI

• Introduction
• A compact micro interferometer LDGI (Laser
  Diffraction Grating Interferometer), could
  generate interference fringe in half pitch
  (416.5nm).
• With signal interpolation at 360 degree, the
  resolution can reach to 1nm.
• The principle of LDGI with a 1nm resolution, as
  show in Figure. Through a series polarization
  phenomenon, the beam will eventually arrive at
  PD1, PD2, PD3 and PD4. The intensity of each PD
  can be expressed by

13

• Tip ball fusing

• Introduction
• The cleaning feature of a commercial optical
  fiber fusion splicer is used to manufacture a
  micro probe. Due to the surface tension , the
  fiber melt by the arc energy will shrink as a
  ball at the tip.
• Typically , the diameter of tip ball is 300 µm
  while fusing the tip ball with 125 µm fiber.
  Furthermore, with the melt-drawn technique , the
  diameter of the tip ball was down to 30 µm.
• Connecting with the plate of the sensor mechanism
  , the tip ball fiber can be used as a CMM touch
  probe.

Tip ball attached to the CMM probe
14

• Development of method to measure the profile of
  inside screw

• Introduction
• Using the motor to drive the mechanism of the
  probe .
• To measure and calculate the x-axis and y-axis
  displacement by LDGI , and can return to the
  original condition in the profile of inside screw.

LDGI
Grating
Linear guide
Inside screw
Motor
Stylus
Pivot
Probe
The flow diagram of the system
Screw thread
To calculate and analysis the Geometry of the
Mechanism.