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Description  |
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BACKGROUND OF THE INVENTION
The present invention relates to a new and unobvious means of printing on a
surface. The present invention is also directed to a new and unobvious
means of forming three dimensional objects from a radiation setable
material by means of a controlled scan of electromagnetic radiation or
other suitable type of radiated energy such as a focusable electron beam.
In the past, printing was done primarily by means of printing plates or the
silk-screen printing process. The processes of the past were directed to
selectively applying ink and drying it whereas the present invention is
directed to selectively curing, hardening or polymerizing a material to
form a desired image or object. These prior art processes did not lend
themselves to printing on large objects, such as the sides of buildings,
tank trucks, billboards and other large or irregularly shaped objects.
Applicant has become aware of U.S. Pat. No. 3,410,203 which discloses a
non-impact printer employing a laser beam and holographic images in which
a toner material is fused to a web with the excess material being drawn
from the web. There is no teaching in this patent of a setable type ink or
polymerizable ink which may be set by means of a laser beam to print
originals. Applicant has also become aware of U.S. Pat. No.
4,024,545-Dowling et al which discloses a laser apparatus which is used to
burn alpha-numeric characters into cardboard boxes. However, no printing
ink of any type is disclosed in this patent, nor is the creation of a
three dimensional object disclosed. U.S. Pat. No. 3,780,214-Bestenreiner
et al discloses a transfer process for making color prints on paper in
which a laser scanning system is used to create a thermal image on a web
which is then transferred to the paper. However, a direct laser printing
process is not disclosed. There is no disclosure of producing three
dimensional objects.
SUMMARY OF THE INVENTION
One advantage of the two dimensional imaging or printing system is that it
may be used to print directly on large and/or irregular shaped objects,
including but not limited to, tractor trailers; custom cars; motorcycles;
buses; ships; airplanes; trains; dirigibles; houses; wall, ceiling and
flooring materials; interior wall surfaces to form murals; glass windows
and doors; the human body; billboards and sides of buildings.
An advantage of the three dimensional imaging system of the present
invention is that it may be used to reproduce an object at a remote
location quickly and accurately by the transmission of electrical signals.
Another advantage of the present invention is that it may be used to
produce raised printing on large and/or irregularly shaped surfaces.
In accordance with the present invention, a material, which may be referred
to as an ink in the two dimensional system, is used which sets, hardens,
cures or polymerizes when irradiated with energy. The terms setable ink or
setable material as used herein include materials which undergo a reaction
in the form of polymerization, curing or hardening when irradiated by
energy in the form of electromagnetic radiation, an electron beam or
similar radiated energy. The energy radiation may be provided from a
coherent source of electromagnetic radiation such as a laser.
Alternatively, and in certain cases preferably, a focusable electron beam
may be used as the radiated energy to set this ink or setable material.
However, it is understood that the source of electromagnetic radiation may
be operated in various frequency ranges which include but are not limited
to infrared, visible light, ultraviolet and other wave lengths. The
present invention is not directed to the mere mechanical fusing or melting
of a material.
In accordance with the present invention, apparatus is provided for
printing on a surface which may be large and/or irregularly shaped. Means
is provided for storing information for forming an image by means of
scanning. This information may be placed in the information storage means
by scanning another image, may be transmitted from a remote location, or
it may be created by means of a keyboard input with or without the use of
further computer processing. A means is provided for applying ink to the
surface to be printed. The means for applying ink may be any suitable
means for providing a uniform coating such as a precision roller or an
airless spray gun. The ink is setable in response to being irradiated by
electromagnetic radiation. The source of energy radiation may be a source
of coherent electromagnetic radiation, such as a laser. For purposes of
description hereinafter, the source of energy radiation will be referred
to as a source of coherent electromagnetic radiation or a laser without in
any way limiting the type of suitable sources of energy radiation which
may be used within the scope of the present invention. Means is provided
for controlling the source of electromagnetic radiation in intensity and
scanning in response to the information stored in the storage means. As
the beam of electromagnetic radiation is scanned across the surface to be
printed, an image is formed on the surface to be printed to form the
desired image. Means is provided for removing from the surface ink which
has not been set. This means for removing the ink may be a vacuum squeegee
which may or may not include means for applying a solvent to aid in the
removal of the ink which has not been set.
The apparatus of the present invention may be used for multicolor printing
on a surface. Means are provided for storing information for forming
images of at least first and second separate colors by means of scanning.
This information which is stored relates to what are sometimes referred to
as color separations in the art which may be produced by scanning an image
through color filters. Alignment markers are formed on the surface to be
printed either prior to the first color setting or after the first color
setting but prior to the second color setting. The alignment markers may
be manually placed or located by the laser. The markers may be printed
markers either preprinted or printed by the laser at the site, or active
or passive signaling devices that respond to irradiation. A setable ink of
a first color is applied to the surface to be printed by applicator means,
such as an airless spray gun or a precision roller. A source of energy
radiation which may be a source of coherent electromagnetic radiation,
such as a laser, is used to selectively irradiate the setable ink to form
the image. Without being limiting, the source of energy radiation will be
referred to as a laser or coherent source of electromagnetic radiation. It
is understood that a controllable electron beam may be preferred in
certain applications. The laser is controlled by a control means which
controls the intensity and the scanning of the laser in response to the
first color information stored in the information storage means. The ink
of the first color which has not been set is removed by an ink removing
means, such as a vacuum squeegee. The ink corresponding to the second
color is applied to the surface by suitable applicator means. The
alignment markers formed or positioned on the surface are detected and the
laser or other source of coherent electromagnetic radiation is positioned
for the second scan in accordance with the second color information stored
in the information storage means. The second color image is set in exact
registry with the first color image by the action of alignment of the
laser with respect to the alignment marks. The second color ink which has
not been set by the laser is removed from the surface by suitable removal
means, such as a vacuum squeegee. The process may be repeated for
additional colors if desired.
In the three dimensional object forming apparatus, a three dimensional
object may be formed in response to the transmission of electrical signals
from a remote location or by the generation of suitable electrical
signals, such as by a computer program similar to the two dimensional
system. The electrical control signals may be generated by scanning an
object to be reproduced or by means of computer and/or human information
inputs.
In the three dimensional object forming apparatus, a transparent container
is provided which contains a quantity of material which is setable upon
being irradiated by energy. A source of a directable beam of energy
radiation which may be a source of coherent electromagnetic radiation is
provided. However it is understood that any suitable source of energy
radiation may be used such as a focusable electron beam or an energy beam
having a Fourier distribution. However, without being limiting, the source
of energy radiation will be referred to as electromagnetic radiation. This
coherent electromagnetic radiation is of a predetermined intensity
sufficient to set the setable material. The intensity of the coherent
electromagnetic radiation is preferrably less than twice the minimum
intensity required to set the material at a particular point in a
predetermined period of time. Means is provided for splitting the beam of
coherent electromagnetic radiation into a plurality of beams. Scan control
means is provided for directing the plurality of beams to converge
simultaneously at a point. This point of convergence is scanned
sequentially through a plurality of points in the material to form a three
dimensional object by means of causing the point of convergence to scan
the entirety of a three dimensional object. After scanning is complete,
any material which has not been set is removed thereby leaving the three
dimensional object.
BRIEF DESCRIPTION OF THE DRAWINGS
For the purpose of illustrating the invention, there are shown in the
drawings forms which are presently preferred; it being understood,
however, that this invention is not limited to the precise arrangements
and instrumentalities shown.
FIG. 1 is a view in perspective of a vehicle mounted direct laser printing
apparatus in accordance with the present invention.
FIG. 2 is a schematic diagram in block diagram form of a scanning apparatus
suitable for placing scan type image information into a computer memory
means.
FIG. 3 is a schematic diagram in block diagram form of a direct laser
printing apparatus in accordance with the present invention.
FIG. 4 is a vacuum type squeegee which includes a solvent applicator which
may be used in accordance with the principles of the present invention for
removing ink which has not been set.
FIG. 5 is a schematic diagram of an apparatus in accordance with the
present invention for forming three dimensional objects utilizing two
beams of radiation.
FIG. 6 is a schematic diagram of an apparatus in accordance with the
present invention for producing three dimensional objects utilizing three
beams of coherent electromagnetic radiation.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings in detail, there is shown in FIG. 1 a two
dimensional printing apparatus 10 carried by a trailer truck 12. However,
it is understood that any suitable vehicle may be used to transport the
two dimensional printing apparatus to the desired locations. The two
dimensional printing apparatus 10 is comprised of a scannable or
directable energy radiation source which may be an electromagnetic
radiation source, such as a laser, and scanning means contained in housing
14. Without being limiting, the terms coherent electromagnetic radiation
source or laser will be used hereinafter. Housing 14 is mounted on a
positionable boom 16. The electronics for controlling the laser in housing
14, ink supply means, ink removal means and other necessary equipment are
contained in the trailer portion 18 of trailer truck 12.
In brief overview, on a surface 20 such as the side of a building to be
printed, alignment markers 22 are placed or formed on the surface 20. The
alignment markers 22 define the area which is to be printed. Preferrably,
alignment markers 22 will be located at the four corners of a square or
rectangle which defines the area to be printed with the markers being
placed outside of the actual printing area. The alignment markers 22 may
be placed on the surface in any suitable manner, such as painting,
adhesively attached markers or other suitable means. The markers may be of
any suitable shape and may include cross hairs for precision alignment.
The alignment markers are used for both printing site definition and
alignment of successive printings of separate colors. They may be detected
by reflection or they may be sensors with connecting means to provide
signal information to the electronics control system upon being
irradiated. The markers may be active or passive sensors, light sources or
any other suitable type of alignment marker.
After the tractor trailer or other suitable vehicle 12 is positioned in
front of the surface 20 to be printed, a means for detecting the alignment
markers 22 is energized. This detector means may preferrably comprise a
separate detector laser and detector optics assembly mounted within the
housing 14. The information obtained from detecting the position of the
alignment markers 22, by angular position sensors (not shown) contained in
the boom 16 control mechanism, is fed into a computer which determines
various parameters for the scanning of the area to be printed. A setable
ink material is then applied to surface 20 within the area defined by
alignment markers 22. The printing laser mounted in housing 14 scans
surface 20 within the area defined by markers 22. The scanning and
intensity of the laser are controlled by information stored in the
computer program, which will be described more fully hereinafter. It is
understood that although lasers are referred to throughout the detailed
description as the presently preferred embodiment, it is understood thay
any suitable source of directable energy radiation may be used within the
sphere and scope of the present invention. Although the two-dimensional
printing apparatus is illustrated as producing a single color or multi
color image on a large object from a distance (for example 20 to 30 feet),
it is understood that the present invention may be used to print on any
size surface, including smaller surfaces, and to print on the surfaces,
such as panelling or sign boards, in an assembly line or conveyor type of
arrangement from shorter distances. In such applications it may be
preferrable to use a different type of energy radiation, such as a
focusable electron beam.
The setable ink which was applied to surface 20 is scanned point by point
by the laser. The intensity of the laser is varied over a complete range
from on to off. Where the setable ink is scanned with the laser beam on,
the ink is set at that point. The plurality of points set by the laser
produce the desired image on surface 20. The terms "set" or "setting"
include any type of ink or substance which polymerizes, hardens or cures
upon being irradiated by electromagnetic radiation. Preferrably, the ink
or setable material undergoes a chemical reaction such as polymerization
and not fusing. By sequentially applying a plurality of coats which are
each individually set by a separate scan of the laser, raised printing may
be produced on the surface.
After the setable ink at a plurality of points has been set by the laser
scan in accordance with the information stored in the computer memory, the
ink or material on surface 20 which has not been set is removed to leave
the desired image. The ink which has not been set is removed by any
suitable means including manually wiping or cleaning the surface. However,
one preferred type of suitable means is shown in FIG. 4 which comprises a
vacuum squeegee and a solvent applicator. Referring to FIG. 4, a suitable
removal means is shown at 30. The removal means comprises a housing 32
mounted on a handle 34. Housing 32 is provided with a plurality of rollers
36 to aid the movement of face 38 of housing 32 over surface 20.
Preferrably, face 38 is moved upwardly along surface 20 with the face 38
moving in the direction of arrow 40.
A suitable removal device may comprise a vacuum squeegee alone, or the
vacuum squeegee device may be used in conjunction with a solvent
applicator. The removal device illustrated in FIG. 4 combines a vacuum
squeegee with a solvent applicator. The solvent is applied to the surface
20 through delivery hose 42 through handle 34, and out of a plurality of
nozzles 44. The solvent and ink which has not been set is removed through
vacuum port 46 which is provided with a vacuum trough 48. The face 38 of
housing 32 is provided with shield or seal 50 and squeegee 52. The leading
part 50 is very soft and flexible providing a seal or shield to prevent
splashing of solvent from spray jets 44 and enhancing the vacuum action
provided by vacuum port 46 and vacuum trough 48. Squeegee 52 is comprised
of a firmer material than seal or shield 50 and provides the squeegee
action in removing residual ink from surface 20. The ink which has been
removed from surface 20, along with the solvent, is carried through vacuum
trough 48, vacuum port 46, handle 34 and vacuum removal hose 54.
Referring now to FIG. 2, there is shown apparatus for generating the
computer usable stored information for controlling the laser in the
production of a printed image. There is shown in FIG. 2 a computer 60
which receives a clock input from clock circuitry 62. The computer 60 is
capable of transferring information to and receiving information from
master program memory 64, tape memory 66, keyboard and display unit 68 and
data and control processor circuitry 70. Although memories 66 and 86
(FIGS. 2 and 3) will be referred to herein as tape memories, it is
understood that any suitable type of memory may be used and may
preferrably be a cassette type disk memory in some applications. These
components are known to those skilled in the art. By way of example, but
not by way of limitation, the computers 60 and 80 (FIGS. 2 and 3) may be a
PDP model 11 computer, the keyboard and display unit 68 may be a model VT
52 Video Display Terminal, and the data and control processor 70 may be a
model ICS Control Subsystem and model AD11-KT Data Acquisition Subsystem,
all of which are manufactured by Digital Equipment Corporation and which
are commercially available. Data and control processor 70 controls laser
72 and laser scan driver 74 under the control of computer 60 and the
master program stored in master program memory 64. A platen 76 is provided
on which an image or picture to be scanned is placed. In the scanning of a
black and white picture for storage in memory 66 and subsequent
reproduction, the print, picture or image is placed on platen 76. The
operator initiates the scan through keyboard and display unit 68, which
signals computer 60 to access master program memory 64. Under the control
of the master program, computer 60 causes data and control processor 70 to
turn on laser 72 which generates a laser beam 73 which is applied to laser
scan driver 74. Data and control processor 70 controls laser scan driver
74 via connection 75. Laser unit 72 includes a sensor (not shown) which
receives light information reflected from the point of scanning of the
image on platen 76 being scanned. As scan driver unit 74 scans the laser
beam across the image on platen 76, the sensor contained within the laser
unit receives the optical information, which is converted into an
electrical signal by the sensor, and the information is transmitted to
data and control processor 70. Data and control processor 70 processes the
data and transmits it to the computer 60, which stores the data on tape
memory 66. At the end of the master program, a signal is transmitted from
compouter 60 to data and control processor 70, which turns off laser 72,
scan driver 74 and tape memory 66. The keyboard and display unit 68 is
then signaled to indicate the end of the processing of image data into
tape memory 66. The information on the tape, disk or other memory means
may then be readily transferred to the electronics in trailer 18 for
control to the printing process either by physically transferring the tape
or by electronic signal transfer means such as radio transmission,
combination on land line and radio transmission, or other suitable
communication systems.
In placing information in tape memory 66 relating to printing in color, the
apparatus of FIG. 2 may be operated in sequence on several color
separation mechanicals placed on platen 76. In other words, a blue color
separation mechanical may be placed on platen 76. After the laser scan is
completed and the information relating to the blue color separation is
stored in the tape memory 66, a red color separation may be placed on
platen 76 and the process repeated. This may be carried out for the
desired number of color separations. The blue and red color separations
are given by way of example, and are not intended to be limiting. The
making of color separation mechanicals or prints from colored images is
well known in the art and equipment is commercially available for such
purposes. The color separation data may be made directly from a multi
color image placed on platen 76 by the use of appropriate color filters.
Referring now to FIG. 3, there is shown a schematic diagram in block
diagram form, of the two dimensional printing apparatus 10 previously
discussed in connection with FIG. 1. There is shown in FIG. 3 a computer
80 which receives a clock input from clock circuitry 82. Clock circuitry
82 may produce a clock output signal of substantially the same frequency
as clock circuit 62 in FIG. 2. Computer 80 receives information from and
transmits information to master program memory 84, tape memory 86,
keyboard and display unit 88, online program storage memory 90 and data
and control processor 92. By way of example, but not by way of limitation,
computer 80 and data and control processor 92 may be of the type of
equipment manufactured by Digital Equipment Corporation which was
mentioned in connection with computer 60 and data and control processor
70, respectively.
Connected with data and control processor 92 are the laser units 94 and 96.
Laser unit 94 preferrably includes a sensor which is not shown. However,
in applications where the alignment markers 22 are sensors connected to or
in communication with the electronics to provide a signal when irradiated,
no sensor is necessary in laser unit 94. Laser unit 96 is provided with a
modulator which forms a part of laster unit 96. Laser unit 94 receives
information from data and control processor 92 and transmits information
back to data and control processor 92. Laser unit 96 receives information
from data and control processor 92 for the control and modulation of the
laser beam 100. The laser beam 98 of laser unit 94, when turned on, and
the laser beam 100 of laser unit 96, when turned on, are applied to
optical switch 102. Optical switch 102 selects the beam which is applied
to scan driver unit 104. Scan driver 104 deflects the laser beam across
the surface 20 to be printed.
In operation, the tape generated in the apparatus of FIG. 2 in tape memory
66 is transferred to tape memory 86. The alignment markers 22, as shown in
FIG. 1, are placed on the surface to be printed. The alignment markers 22
may be, but do not have to be retroflective. They may be sensors that are
wired back to the system, or sensors which contain miniature transmitters
to relay the information back to the system. However, it is understood
that the present invention is not limited to any of these particular types
of markers, but may be of any suitable type which serves the purpose
within the spirit of the present invention.
The operator, after suitable positioning of housing 14 in FIG. 1 with
respect to the surface 20 to be printed, initiates the process through
keyboard and display unit 88. Keyboard and display unit 88 signals
computer 80 to access master program memory unit 84, and particularly a
scanning and set up program 106. The computer 80 in response to scanning
and set up master program 106, via data and control processor 92, switches
optical switch 102 to receive laser beam 98 from laser unit 94 and then
turns on laser unit 94. Data and control processor 92 controls scan driver
unit 104 causing the laser beam output of laser unit 94 to be scanned
across the surface 20 to be printed, and particularly scans for the
detection of alignment markers 22. The detection of alignment markers 22
is done preferrably by means of a sensor in laser unit 94. The information
from the sensor in laser unit 94 is transmitted to data and control
processor unit 92 for further transmission to computer 80, which causes
the information to be stored in online program storage unit 90 at 108. At
the end of the scanning and set up program 106, a signal is transmitted
through computer 80 to data and control processor 92 which turns off laser
unit 94 and scan driver 104. The keyboard and the display unit 88 is then
signaled to indicate the end of the scanning operation.
The operator then initiates the generation of the print program through
keyboard and display unit 88 by signaling computer 80 to access master
program memory 84 for master print program generation program 110 to cause
the computer to access the data in tape memory 86 and combine this data
with the data stored in on-line storage memory 108 to formulate the print
program. The formulated print program is stored in on-line storage unit
112. Assuming that it is desired to print a color image on surface 20, the
operator then applies to surface 20 the color corresponding to the color
information presently stored in storage 112. Application of the ink may be
by a precision roller or by a spray device which applies an even coating
of setable ink over the surface 20 to be printed. The spray device may
preferrably be an airless spray gun.
Upon completion of the application of the setable ink or material to the
surface 20, computer 80 initiates the actual printing process or setting
of the ink by accessing a master print program 114 in master program
memory 84. The computer 80, in accordance with the master print program
114, uses the data stored in on-line program memory 112 for control of
data and control processor 92. Data and control processor 92, in response
to this information, switches optical switch 102 to proper position for
laser unit 96. Data and control processor 92 turns on laser unit 96 and
controls scan driver 104 via connection 103. Data and control processor
92, provides data to simultaneously control the modulator of laser unit
96. The laser beam 100, as deflected by scan driver unit 104, scans the
surface 20 to be printed while being simultaneously modulated in
accordance with the print data. Upon the completion of the print data from
on-line storage 112, a signal is transmitted from print program 114
through computer 80 to data and control processor 92 which turns off laser
unit 96 and scan driver unit 104. Keyboard and display unit 88 is then
signaled to indicate the end of the printing scan for that particular
color.
The ink which has not been set during the scanning process is then removed
as previously described in connection with FIGS. 1 and 4. The process may
then be repeated for additional separate colors. The scanning process by
laser unit 94 for subsequent colors detects the same alignment markers 22
thereby insuring that the subsequent separate color printing will be
accomplished in exact registry with the image previously printed on
surface 20. It is also within the present invention to produce raised
printing on the surface 20 by repeatedly printing, coating and setting the
setable material, with the same subject matter being printed, thereby
building up the printed material to an extent where it is raised from the
surface.
In accordance with the present invention, three dimensional objects may be
formed. The forming of the three dimensional objects may be from
information obtained by scanning a similar object at a remote or nearby
location. Alternatively, the information for the formation of the object
in accordance with the present invention may be computer generated from
instructions, that is, not generated in response to the scanning of
another object.
Generally, and in accordance with the present invention, a transparent
container is provided for containing a quantity of material which is
setable upon being irridiated by energy radiation. The source of energy
radiation may be a source of coherent electromagnetic radiation such as a
laser, preferrably operating in the ultra violet frequency spectrum. The
energy radiation may preferrably be a focusable electron beam or Fourier
distribution beams to reduce losses in passing through the material.
However, without intending to limit the types of energy radiation which
may be used in practicing the present invention, the invention will be
described herein as utilizing a source of coherent electromagnetic
radiation such as a laser. A computer system, similar to that used in the
two dimensional system, with an expansion to accept information and
controls relating to a third dimension may be utilized. The
electromagnetic radiation used to set (polymerize, harden or cure) the
setable material selectively to form the object is derived from a coherent
beam of electromagnetic radiation, such as a laser beam, which is of
sufficient intensity to set the material at the normal scanning rate, but
is preferrably less than twice the minimum required intensity. The
coherent electromagnetic radiation beam or laser beam is split into two or
more beams which are deflected or directed to recombine at a point within
the setable material. The recombination point is caused by the deflection
means to scan the form of a three dimensional object. The point at which
the beams recombine receives sufficient electromagnetic radiation to cause
setting of the setable material. As the composite point is caused to scan
the entirety of a three dimensional object, such three dimensional object
is formed in the setable material. Upon completion of the scanning, any
unset material is removed. In this manner complete and accurate
reproduction of objects can be produced at a remote point in the setable
material. In this manner, an object may be scanned in New York, the
information electronically transmitted to the west coast with the object
reproduced on the west coast by means of the present invention. The
present invention may also be used to produce objects locally from various
forms of computerized data. For example, the present invention may be used
in conjunction with axial tomography in the medical field wherein the data
is presently recorded and displayed on paper or a video display. This data
may now be produced in the form of a three dimensional object. For
example, the computerized axial tomography data of a patient's heart with
a bad mitral valve may be produced in exact exterior and interior detail
in a three dimensional object. Physicians and surgeons may then dissect
the valve area and evaluate a prosthetic valve for fit within the area
concerned. Similarly, various other volumetric measurements may now be
computed simply with this system by the placing of fluids into the heart
chanbers of a model produced in accordance with the present invention, and
then measuring the quantity of the fluid removed from the object. This
would provide accurate measurements of volumes which now can only be
approximated because of the elaborate dimensions of the interior of each
individual' s heart. Costly anatomic models may be produced by the present
invention inexpensively and in precise detail.
Referring now to FIGS. 5 and 6, the apparatus of a system for producing
three dimensional objects in accordance with the present invention is
shown in greater structural detail. Referring now particularly to FIG. 5,
there is shown a source of electro-magnetic radiation 200 which may be in
the form of a laser, and will be referred to herein as a laser. However,
it is understood that other suitable sources of coherent electromagnetic
radiation may be used in the present invention. The laser 200 produces a
laser beam output 202 which is split in laser beam splitter and deflector
means 204 into laser beams 206 and 208. The intensity of laser beam 202 is
of sufficient magnitude to set the setable material upon being irradiated
at the normal scan rate. The intensity of laser beam 202 is selected or
adjusted so that the individual beams 206 and 208 are of insufficient
intensity to set the setable material at the normal scan rate. However,
when the plurality of beams are recombined at a single point within the
setable material, setting does occur. In essence, the laser beam output of
laser 200 is split into a plurality of beams, each of which is
insufficient to cause the setting of the setable material at the normal
scan rate, but which when recombined at a point cause a sufficient
intensity of electromagnetic radiation at that point to set the setable
material.
Laser beam 208 may be deflected by a fixed mirror or surface 210 to
deflecting or scanning means 212. The deflection means or scanning means
in laser beam splitter and deflector 204 and deflector means 212 cause the
laser beams 206 and 208 to be recombined at a point within the setable
material identified by number 214. The deflection means within laser beam
splitter and deflector means 204 and deflector means 212 cause the
recombination point 214 to be scanned throughout the material to form the
object to be created.
The setable material is contained within a transparent container 216. The
transparent container may be provided with a recirculation means 218. The
recirculation means may be provided to prevent any possible setting of the
material at undesired locations due to a single portion of the laser beam,
such as split portion 206 or split portion 208 being scanned repeatedly
through a particular point. The recirculation means may be operated
intermittently between periods of scan of the laser beams to prevent any
possible interference with the desired object formation.
Computer control circuitry 220 is indicated to provide the intensity
control to laser 200, and the scanning or deflecting control signals to
the deflector in laser beam splitter and deflector means 204 and deflector
means 212. Both of the deflector means are capable of deflecting the laser
beams in two orthogonal directions. The computer control circuitry may be
similar in structure to that disclosed with respect to the two dimensional
printing system described in connection with FIG. 3 with the addition of
controls for the additional scanning in three dimensions.
Referring now to FIG. 6, there is shown another embodiment of an apparatus
in accordance with the present invention for producing three dimensional
objects in which the laser beam is split into three beams which are
recombined at a point in the setable material by three scanners which may
be referred to as the "X", "Y" and "Z" scanners. Referring to FIG. 6 there
is shown a s | | |
