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Claims  |
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We claim:
1. A vision head for a vision metrology
system, comprising:
a primary prism,
a primary objective lens,
zoom optics means comprising a plurality of lenses
a sensor,
said primary prism, primary objective lens, and said zoom optics means
comprising an optical path through which an image of an object may pass
onto said sensor,
said primary prism comprising structure positioned to allow light to pass
therethrough by way of a first path which coincides with said optical path
and by way of a second path having an initial portion which is different
from said first path and which intercepts said first path and then merges
with said first path,
a reseau pattern means having a plurality of reseaus formed in a given
pattern,
light means for projecting an image of said reseaus through said primary
prism onto said sensor by way of said second path for use for correcting
in real-time, optical distortion of the image of the object passing
through said plurality of lenses of said zoom optics means.
2. The vision head of claim 1, comprising:
reseau optical lens means, and
means for directing light, passing through said reseau pattern means, to
said reseau optical lens means for passage therethrough to said primary
prism and then to said sensor by way of primary objective lens and said
zoom optics means.
3. The vision head of claim 2, comprising:
a laser for projecting a primary beam of light,
a beam splitter for dividing said primary beam of light into a pointer beam
and into a range-finder beam,
a reflecting surface in said primary prism,
said optical path having an optical axis,
said pointer beam being reflected by said beam splitter to said reflecting
surface,
said reflecting surface being positioned to reflect said pointer beam
forward and cocident with the optical axis of said optical path,
optical means for directing said range-finder beam in a direction to
intercept said pointer beam at a given distance forward of said primary
prism,
a shutter for controlling said pointer beam, and
a shutter for controlling said range-finder beam.
4. The vision head of claim 1, comprising:
a laser for projecting a primary beam of light,
a beam splitter for dividing said primary beam of light into a pointer beam
and into a range-finder beam,
a reflecting surface in said primary prism,
said optical path having an optical axis,
said pointer beam being reflected by said beam splitter to said reflecting
surface,
said reflecting surface being positioned to reflect said pointer beam
forward an coincident with the optical axis of said optical path,
optical means for directing said range-finder beam in a direction to
intercept said pointer beam at a given distance forward of said primary
prism,
a shutter for controlling said pointer beam, and
a shutter for controlling said range-finder beam.
5. The vision head of claim 1, comprising:
said primary objective lens being adjustable in position along said optical
path relative to said sensor,
primary objective lens adjusting means for adjusting the position of said
primary objective lens along said optical path relative to said sensor,
said plurality of lenses of said zoom optics means having an adjustable
magnification,
zoom optics adjusting means for adjusting the magnification of said
plurality of lenses of said zoom optics means,
said reseau pattern means being adjustable in position along said initial
portion of said second path,
reseau pattern adjusting means for adjusting the position of said reseau
pattern means along said initial portion of said second path corresponding
with the adjustment of said primary objective lens along said optical
path,
aperture means located in said optical path for allowing light to pass
along said optical path to said sensor,
said aperture means having an aperture with an adjustable size for
controlling the passage of light therethrough, and
aperture adjusting means for controlling said aperture means for adjusting
the size of said aperture.
6. A vision unit, including the vision head of claim 5, and comprising:
mount means for mounting said vision head for movement about a first axis
and a second axis perpendicular to said first axis,
first head position adjusting means coupled to said mount means for
controlling movement of said vision head about said first axis, and
second head position adjusting means coupled to said mount means for
controlling movement of said vision head about said second axis.
7. The vision head of claim 5, comprising:
a programmable computer means, and
control means responsive to said programmable computer means for
controlling said primary objective lens adjusting means, said zoom optics
adjusting means, said reseau pattern adjusting means, and said aperture
adjusting means.
8. A vision unit, including the vision head of claim 1, and comprising:
mount means for mounting said vision head for movement about a first axis
and a second axis perpendicular to said first axis,
first head position adjusting means coupled to said mount means for
controlling movement of said vision head about said first axis, and
second head position adjusting means coupled to said mount means for
controlling movement of said vision head about said second axis.
9. The vision unit of claim 8, comprising:
a programmable computer means, and
control means responsive to said programmable computer means for
controlling said first and second head position adjusting means.
10. The vision unit of claim 8, comprising:
an optically collimated reference mark on said mount means for allowing
precise measurements along said first and second head position axes.
11. The vision unit of claim 8, comprising:
an azimuth servo system and an elevation servo system for controlling
movement of said vision head about said first and second axes
respectively,
said azimuth servo system comprising:
an azimuth servo motor for rotating said vision head about said first axis,
a control means for producing an azimuth position control signal
representative of a desired angular position of said vision head relative
to said first axis,
an azimuth low-resolution control counter responsive to said azimuth
position control signal for producing an azimuth low-resolution output
representative of the desired angular position of said vision head
relative to said first axis,
azimuth encoder means for converting the actual angular position of said
vision head relative to said first axis to an actual azimuth position
signal,
means for transforming said actual azimuth position signal into an azimuth
low-resolution feedback signal and an azimuth high-resolution feedback
signal,
an azimuth low-resolution feedback counter responsive to said azimuth
low-resolution feedback signal for producing an azimuth low-resolution
output representative of the actual angular position of said vision head
relative to said first axis,
an azimuth control feedback error register for comparing the output of said
azimuth lowresolution control counter and the output of said azimuth
low-resolution feedback counter for producing an azimuth low-resolution
position error output,
an azimuth high-resolution counter responsive to said azimuth
high-resolution feedback signal for producing an azimuth high-resolution
output representative of the actual angular position of said vision head
relative to said first axis,
an azimuth error encoder multiplexer for combining said azimuth
low-resolution position error output and the output of said azimuth
high-resolution counter to produce an azimuth position error signal,
means for applying said azimuth position error signal to said azimuth servo
motor for causing rotation of said vision head about said first axis so as
to minimize said azimuth position error signal,
said elevation servo system comprising:
an elevation servo motor for rotating said vision head about said second
axis,
an elevation low-resolution control counter responsive to said elevation
position control signal for producing an elevation low-resolution output
representative of the desired angular position of said vision head
relative to said second axis,
elevation encoder means for converting the actual angular position of said
vision head relative to said second axis to an actual elevation position
signal,
means for transforming said actual elevation position signal into an
elevation low-resolution feedback signal and an elevation high-resolution
feedback signal,
an elevation low-resolution feedback counter responsive to said elevation
low-resolution feedback signal for producing an elevation low-resolution
output representative of the actual angular position of said vision head
relative to said second axis,
an elevation control feedback error register for comparing the output of
said elevation low-resolution control counter and the output of said
elevation low-resolution feedback counter for producing an elevation
low-resolution position error output,
an elevation high-resolution counter responsive to said elevation
high-resolution feedback signal for producing an elevation high-resolution
output representative of the actual angular position of said vision head
relative to said second axis,
an elevation error encoder multiplexer for combining said elevation
low-resolution position error output and the output of said elevation
high-resolution counter to produce an elevation position error signal, and
means for applying said elevation position error signal to said elevation
servo motor for causing rotation of said vision head about said second
axis so as to minimize said elevation position error signal.
12. The vision unit of claim 8, comprising:
said primary objective lens being adjustable in position along said optical
path relative to said sensor,
primary objective lens adjusting means for adjusting the position of said
primary objective lens along said optical path relative to said sensor,
said plurality of lenses of said zoom optics means having an adjustable
magnification,
zoom optics adjusting means for adjusting the magnification of said
plurality of lenses of said zoom optics means,
said reseau pattern means being adjustable in position along said initial
portion of said second path,
reseau pattern adjusting means for adjusting the position of said reseau
pattern means along said initial portion of said second path corresponding
with the adjustment of said primary objective lens along said optical
path,
aperture means located in said optical path for allowing light to pass
along said optical path to said sensor,
said aperture means having an aperture with an adjustable size for
controlling the passage of light therethrough,
aperture adjusting means for controlling said aperture means for adjusting
the size of said aperture,
a programmable computer means, and
control means responsive to said programmable computer means for
controlling said primary objective lens adjusting means, said zoom optics
adjusting means, said reseau pattern adjusting means, said aperture
adjusting means, and said first and second head position adjusting means.
13. The vision head of claim 1 comprising:
means for storing known coordinates of said reseaus of said predetermined
pattern, as they exist prior to passage thereof through said primary
prism, and
computer means for determining:
(a) the coordinates of the image reseaus detected by said sensor,
(b) the coordinates of the image of points of interest of the object
detected by said sensor,
(c) the distortion-corrected image coordinates of the imaged object points
of interest from their detected sensor coordinates by employing
coordinates of the imaged reseaus detected by said sensor and said known
coordinates of said reseaus.
14. The vision head of claim 1, wherein said plurality of reseaus in said
given pattern comprises:
a plurality of reseaus in each of a plurality of radial lines extending
outward in a plane from a central point.
15. The vision head of claim 14, wherein:
said reseaus in each line increase in size outward from said central point.
16. The vision head of claim 1, wherein:
the image of the reseaus, upon passage to said sensor, has an axis between
said primary prism and said sensor which is the same as said optical axis
of said optical path,
the image of the object, upon passage through said optical path to said
sensor, has an axis which is the same as said optical axis of said optical
path.
17. The vision head of claim 16, wherein:
said sensor comprises an area array sensor having a plurality of pixels in
rows and columns.
18. The vision head of claim 1, wherein:
said sensor comprises an area array sensor having a plurality of pixels in
rows and columns.
19. A vision unit, comprising:
a vision head,
said vision head comprising:
a prism,
a primary objective lens,
zoom optics means comprising a plurality of lenses,
a sensor,
said prism, primary objective lens, and said zoom optics means comprising
an optical path through which the image of an object may pass onto said
sensor,
said primary objective lens and said zoom optics means being located along
said optical path between said prism and said sensor,
a reseau pattern means having a plurality of reseaus formed in a given
pattern, and
light means for projecting an image of said reseaus to said prism and then
through said optical path onto said sensor for use for correcting in
real-time, optical distortion of the image of the object passing through
said plurality of lenses of said zoom optics means.
mount means for mounting said vision head at a position where two
perpendicular axes intersect each other,
said mount means mounting said vision head for rotational movement about
each of said two axes at the intersection of said two axes,
a first position adjusting means coupled to said mount means for
controlling movement of said vision head about one of said axes,
a second position adjusting means coupled to said mount means for
controlling movement of said vision head about the other of said axes, and
control means coupled to first and second position adjusting means for
automatically controlling movement of said vision head about said two
perpendicular axes.
20. The vision unit of claim 19, wherein:
said vision head comprises aperture means having an aperture for allowing
the passage of light therethrough,
said aperture having a size which is adjustable.
21. The vision unit of claim 20, wherein:
said primary objective lens is adjustable in position along said optical
path relative to said sensor,
primary objective lens adjusting means for adjusting the position of said
primary objective lens along said optical path relative to said sensor.
22. The vision unit of claim 21, wherein:
said plurality of lenses of said zoom optics means have a variable
magnification,
means for continuously varying the magnification of said plurality of
lenses of said zoom optics means.
23. The vision unit of claim 20, wherein:
said plurality of lenses of said zoom optics means have a variable
magnification,
means for continuously varying the magnification of said plurality of
lenses of said zoom optics means.
24. The vision unit of claim 19, comprising:
an azimuth servo system and an elevation servo system for controlling
movement of said vision head about said first and second axes
respectively,
said azimuth servo system comprising:
an azimuth servo motor for rotating said vision head about said first axis,
a control means for producing an azimuth position control signal
representative of a desired angular position of said vision head relative
to said first axis,
an azimuth low-resolution control counter responsive to said azimuth
position control signal for producing an azimuth low-resolution output
representative of the desired angular position of said vision head
relative to said first axis,
azimuth encoder means for converting the actual angular position of said
vision head relative to said first axis to an actual azimuth position
signal,
means for transforming said actual azimuth position signal into an azimuth
low-resolution feedback signal and an azimuth high-resolution feedback
signal,
an azimuth low-resolution feedback counter responsive to said azimuth
low-resolution feedback signal for producing an azimuth low-resolution
output representative of the actual angular position of said vision head
relative to said first axis,
an azimuth control feedback error register for comparing the output of said
azimuth low-resolution control counter and the output of said azimuth
low-resolution feedback counter for producing an azimuth low-resolution
position error output,
an azimuth high-resolution counter responsive to said azimuth
high-resolution feedback signal for producing an azimuth high-resolution
output representative of the actual angular position of said vision head
relative to said first axis,
an azimuth error encoder multiplexer for combining said azimuth
low-resolution position error output and the output of said azimuth high
resolution counter to produce an azimuth position error signal,
means for applying said azimuth position error signal to said azimuth servo
motor for causing rotation of said vision head about said first axis so as
to minimize said azimuth position error signal,
said elevation servo system comprising:
an elevation servo motor for rotating said vision head about said second
axis,
an elevation low-resolution control counter responsive to said elevation
position control signal for producing an elevation low-resolution output
representative of the desired angular position of said vision head
relative to said second axis,
elevation encoder means for converting the actual angular position of said
vision head relative to said second axis to an actual elevation position
signal,
means for transforming said actual elevation position signal into an
elevation low-resolution feedback signal and an elevation high-resolution
feedback signal,
an elevation low-resolution feedback counter responsive to said elevation
low-resolution feedback signal for producing an elevation low-resolution
output representative of the actual angular position of said vision head
relative to said second axis,
an elevation control feedback error register for comparing the output of
said elevation low-resolution control counter and the output of said
elevation low-resolution feedback counter for producing an elevation
low-resolution position error output,
an elevation high-resolution counter responsive to said elevation
high-resolution feedback signal for producing an elevation high-resolution
output representative of the actual angular position of said vision head
relative to said second axis,
an elevation error encoder multiplexer for combining said elevation
low-resolution position error output and the output of said elevation
high-resolution counter to produce an elevation position error signal, and
means for applying said elevation position error signal to said elevation
servo motor for causing rotation of said vision head about said second
axis so as to minimize said elevation position error signal.
25. In an optical system comprising a primary prism, a primary objective
lens, zoom optics means comprising a plurality of lenses, an area array
sensor, light means, and a reseau pattern means comprising a
two-dimensional pattern of reseaus wherein said primary prism, said
primary objective lens, and said zoom optics means comprise an optical
path through which an image of an object may pass onto said sensor, said
primary prism comprising structure positioned to allow light to pass
therethrough by way of a first path which coincides with said optical path
and by way of a second path having an initial portion which is different
from said first path and which intercepts said first path and then merges
with said first path, said light means and said reseau pattern means being
located such that said light means, when actuated, projects an image of
said predetermined pattern of said reseaus through said primary prism by
way of said second path, a process of obtaining information for correcting
in real-time, optical distortion of the image of the object passing
through said plurality of lenses of said zoom optics means comprising the
steps of:
projecting the image of an object onto said sensor through said optical
path and hence through said first path by way of said primary prism, said
primary objective lens, and said plurality of said lenses of said zoom
optics means, and
actuating said light means to project the image of said predetermined
two-dimensional pattern of said reseaus through said second path onto said
sensor by way of said primary prism, said primary objective lens, and said
plurality of said lenses of said zoom optics means for use for correcting
for said distortion.
26. The process of claim 25, wherein:
said predetermined two-dimensional pattern of said reseaus comprises:
a plurality of reseaus in each of a plurality of radial lines extending
outward in a plane from a central axis.
27. The process of claim 26, wherein:
said reseaus in each line increase in size outward from said central axis.
28. In an optical system comprising a primary prism, a primary objective
lens, zoom optics means comprising a plurality of lenses, and an area
array sensor wherein said primary prism, said primary objective lens, and
said zoom optic means comprise an optical path through which an image of
an object may pass onto said sensor, a process of correcting in real-time,
optical distortion of the image of the object passing through said
plurality of lenses of said zoom optics means, comprising the steps of:
projecting the image of an object onto said sensor by way of said primary
prism, said primary objective lens, and said plurality of said lenses of
said zoom optics means,
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