Solid imaging system

Claim 1

A process for maintaining a constant exposure level during fabrication of an integral three-dimensional rigid object from successive thin layers of a liquid photohardenable composition comprising the steps of: storing graphic data, corresponding to the shape of the rigid object desired to be fabricated, in a first computer control means, placing the liquid photohardenable composition in a vessel, generating a radiation beam having an intensity by using radiaton means, using said first computer control means, controllably deflecting said radiation beam in a vector scanning mode to predetermined positions on the successive thin layers in order to induce photohardening of preselected portions of the liquid photohardenable composition to a depth of photohardening, and also deflecting the radiation beam with an acceleration from zero level to a maximum accelertion, and with a velocity from zero level to a maximum velocity by using deflection means, coupling a second computer control means with, said deflection means, and said first computer control means, said second computer control means being used in conjunction with a modulation means for controllably modulating the intensity of the radiation beam from a substantially zero intensity level to a maximum intensity, in proportion to the velocity of said beam, thereby providing a substantially constant exposure level, said exposure level being substantially independent of the velocity of said beam, on the predetermined portions of the liquid photohardenable composition in order to achieve substantially constant depth of photohardening within each successive thin layer, supporting the rigid object on a movable substantially flat table within the vessel, controllably moving the flat table by using placement means, the placement means being controlled by the first computer control means, and forming the successive thin layers of the liquid photohardenable composition by layer forming means, the layer forming means being controlled also by the first computer control means.

Claim 14

An apparatus for maintaining a constant exposure level during fabrication of an integral three-dimensional rigid object from successive thin layers of a liquid photohardenable composition comprising: a vessel for containing the liquid photohardenable composition, radiation means for providing a radiation beam, the radiation beam having an intensity, modulation means for modulating the intensity of the radiation beam from substantially zero intensity level to a maximum beam intensity, deflection means for controllably deflecting the radiation beam in a vector scanning mode to predetermined positions on the successive thin layers in order to induce photohardening of pre-selected portions of the liquid photohardenable composition to a depth of photohardening, the deflection means also controllably deflecting the beam with an acceleration from zero level to a maximum acceleration, and with a velocity from zero level to a maximum constant velocity, first computer control means for storing graphic data corresponding to the shape of the desired rigid object, second computer control means coupled with said modulation means, said deflection means, and said first computer control means, said second computer control means being for providing a substantially constant exposure level, said exposure level being substantially independent of the velocity of said beam, on the predetermined portions of the liquid photohardenable composition in order to achieve substantially constant depth of photohardening within each successive thin layer, a substantially flat movable table within the vessel for supporting the rigid object, placement means controlled by the first computer control means for providing a motion to the movable table in order to accurately control placement of the moveable table within the vessel, and layer forming means located over the movable table, the layer forming means also being controlled by the first computer control means for forming the successive thin layers of the liquid photohardenable composition.

Claim 15

An apparatus for maintaining a constant exposure level during fabrication of an integral three-dimensional rigid object from successive thin layers of a liquid photohardenable composition comprising: a vessel for containing the liquid photohardenable composition, radiation means for providing a radiation beam, the radiation beam having an intensity, modulation means for modulating the intensity of the radiation beam from substantially zero intensity level to a maximum beam intensity, deflection means for controllably deflecting the radiation beam in a vector scanning mode to predetermined positions on the successive thin layers in order to induce photohardening of pre-selected portions of the liquid photohardenable composition to a depth of photohardening, the deflection means also controllably deflecting the beam with an acceleration from zero level to a maximum acceleration, and with a velocity from zero level to a maximum constant velocity, first computer control means for storing graphic data corresponding to the shape of the desired rigid object, second computer control means coupled with said modulation means, said deflection means, and said first computer control means, said second computer control means being for providing a substantially constant exposure level, said exposure level being substantially independent of the velocity of said beam, on the predetermined portions of the liquid photohardenable composition in order to achieve substantially constant depth of photohardening within each successive thin layer, a substantially flat movable table within the vessel for supporting the rigid object, placement means controlled by the first computer control means for providing a motion to the movable table in order to accurately control placement of the moveable table within the vessel, and layer forming means located over the movable table, the layer forming means also being controlled by the first computer control means for forming the successive thin layers of the liquid photohardenable composition.