Patent ID: 8083307

Claim:
A method of fabricating a three-dimensional structure, the method comprising the steps of: depositing a droplet of curable ink on a substrate; curing the ink deposited on the substrate; and building up the ink in layers by repeatedly depositing a droplet of curable ink on the cured ink and curing the deposited ink, while doing at least one of a control of a contact angle between the droplet of ink to be deposited and cured ink at the landing position where the droplet of ink is to be deposited and a control of a volume of the droplet of ink to be deposited so as to satisfy the condition d n ≦d n−1 , where d n represents the landing diameter of a droplet of ink to be deposited and d n−1 represents the diameter of cured ink at a landing position where the droplet of ink is to be deposited, wherein the building up step uses the following formula to calculate the contact angle θ n or the droplet volume V n V n = 24 π ⁢ { d n 3 ( 2 - 3 ⁢ ⁢ cos ⁢ ( ϕ n - 1 + θ n ) + cos 3 ⁡ ( ϕ n - 1 + θ n ) sin 3 ⁡ ( ϕ n - 1 + θ n ) - 1 tan 3 ⁢ ϕ n - 1 ) - d n ⁢ 3 ⁢ ⁢ d n - 1 2 tan ⁢ ⁢ ϕ n - 1 ⁢ sin 2 ⁢ θ n - 1 - 2 ⁢ d n - 1 3 sin 3 ⁢ θ n - 1 } where θ n is the contact angle between the droplet of ink to be deposited and the cured ink at the landing position of the droplet of ink to be deposited, θ n−1 is the contact angle between the cured ink at the landing position of the droplet of ink to be deposited and a body on which the cured ink at the landing position of the droplet of ink to be deposited has landed, Φ n−1 is an angle between a tangent on the surface of the cured ink at the landing position where the droplet of ink is to be deposited, at a point of contact between the surface of the droplet of ink to be deposited and the cured ink at the landing position of the droplet of ink to be deposited, and a plane which is parallel to the surface of the substrate, and V n is the volume of the droplet of ink to be deposited.