Method for manufacturing phase gratings of a combination pattern-refraction modification type

Claim 2

A process for manufacturing a phase grating having combined pattern modification and refraction modification, comprising the steps of: (1) forming a thin film of composition which includes: (A) a polymer having double bonds between two carbons containing the moiety ##STR7## where R 1 represents a hydrogen atom or an alkyl substituent of one to four carbons, and R 2 represents a substituent including at least one non-conjugated carbon-carbon double bond, and (B) at least one aromatic aldehyde or aromatic ketone which absorbs ultraviolet rays of 300 to 400 nm wavelength; (2) irradiating the thin film in a regularly arranged pattern of ultraviolet rays, whereby compound (B) reacts with polymer (A) in the areas of irradiation; and (3) removing non-reacted compound (B), whereby a regularly pattern of irradiated areas of reaction product having a greater thickness and a greater refractive index than areas not irradiated of polymer (A) without compound (B) is realized.

Claim 3

A process according to claim 1, in which the aromatic aldehyde and the aromatic ketone comprise at least one carbonyl group and have the following general formula (II) or (III): ##STR8## where X 1 to X 6 represent hydrogen, alkyl group of one to seven carbons, alkoxy group or allyloxy group of one to seven carbons, or halogen and X 7 to X 10 represent hydrogen or halogen, and n represents zero or an integer.

Claim 4

A method according to claim 2, in which the aromatic ketone has a triplet energy within a range from 65 kcal/mol to 77 kcal/mol.

Claim 5

A process according to claim 1 in which the mol ratio of said compound (B) to substituent R 2 in polymer (A) is in the range of 10:1 to 1:20.

Claim 6

A method according to claim 4 wherein the mol ratio is in the range of 5:1 to 1:10.

Claim 7

A method according to claim 4 in which the polymer is an acrylic acid or methacrylic acid ester polymer.

Claim 8

A process for manufacturing a phase grating having combined pattern modification and refraction modification, comprising the steps of: (1) forming a thin film of composition which includes: (A) a polymer having double bonds between two carbons containing the moiety ##STR9## where R 1 represents a hydrogen atom or an alkyl substituent of one to four carbons, and R 2 represents a substituent including at least one non-conjugated carbon-carbon double bond, and (B) at least one aromatic aldehyde or aromatic ketone which absorbs ultraviolet rays of 300 to 400 nm wavelength; (2) irradiating the thin film in a regularly arranged pattern of ultraviolet rays, whereby compound (B) reacts with polymer (A) in the areas of irradiation; and (3) removing non-reacted compound (B) by heating under a reduced pressure, whereby a regularly pattern of irradiated areas having a greater thickness and a greater refractive index than areas not irradiated is realized.

Claim 9

A process for manufacturing a phase grating having combined pattern modification and refraction modification, comprising the steps of: (1) forming a thin film of composition which includes: (A) a polymer having double bonds between two carbons containing the moiety ##STR9## where R 1 represents a hydrogen atom or an alkyl substituent of one to four carbons, and R 2 represents a substituent including at least one non-conjugated carbon-carbon double bond, and (B) at least one aromatic aldehyde or aromatic ketone which absorbs ultraviolet rays of 300 to 400 nm wavelength; (2) irradiating the thin film in a regularly arranged pattern of ultraviolet rays, whereby compound (B) reacts with polymer (A) in the areas of irradiation; and (3) removing non-reacted compound (B) by heating under a reduced pressure, whereby a regularly pattern of irradiated areas having a greater thickness and a greater refractive index than areas not irradiated is realized.

Claim 10

A process for manufacturing a phase grating having combined pattern modification and refraction modification, comprising the steps of: (1) forming a thin film of composition which includes: (A) a polymer having double bonds between two carbons containing the moiety ##STR10## where R 1 represents a hydrogen atom or an alkyl substituent of one to four carbons, and R 2 represents a substituent including at least one non-conjugated carbon-carbon double bond, and is the residue obtained upon removal of hydroxyl from a terpene (B) at least one aromatic aldehyde or aromatic ketone which absorbs ultraviolet rays of 300 to 400 μm wavelength; (2) irradiating the thin film in a regularly arranged pattern of ultraviolet rays, whereby compound (B) reacts with polymer (A) in the areas of irradiation; and (3) removing non-reacted compound (B), whereby a regularly pattern of irradiated areas having a greater thickness and a greater refractive index than areas not irradiated is realized.

Claim 11

A process for manufacturing a phase grating having combined pattern modification and refraction modification, comprising the steps of: (1) forming a thin film of composition which includes: (A) a polymer having double bonds between two carbons containing the moiety ##STR10## where R 1 represents a hydrogen atom or an alkyl substituent of one to four carbons, and R 2 represents a substituent including at least one non-conjugated carbon-carbon double bond, and is the residue obtained upon removal of hydroxyl from a terpene (B) at least one aromatic aldehyde or aromatic ketone which absorbs ultraviolet rays of 300 to 400 μm wavelength; (2) irradiating the thin film in a regularly arranged pattern of ultraviolet rays, whereby compound (B) reacts with polymer (A) in the areas of irradiation; and (3) removing non-reacted compound (B), whereby a regularly pattern of irradiated areas having a greater thickness and a greater refractive index than areas not irradiated is realized.

Claim 12

A process for manufacturing a phase grating having combined pattern modification and refraction modification, comprising the steps of: (1) forming a thin film of composition which includes: (A) a polymer having double bonds between two carbons which is a copolymer of methyl methacrylate and 2-butenyl methacrylate, and (B) at least one aromatic aldehyde or aromatic ketone which absorbs ultraviolet rays of 300 to 400 nm wavelength and is benzophenone or 3-benzoyl-benzophenone; (2) irradiating the thin film in a regularly arranged pattern of ultraviolet rays, whereby compound (B) reacts with polymer (A) in the areas of irradiation; and (3) removing non-reacted compound (B), whereby a regularly pattern of irradiated areas having a greater thickness and a greater refractive index than areas not irradiated is realized.

Claim 13

A process for manufacturing a phase grating having combined pattern modification and refraction modification, comprising the steps of: (1) forming a thin film of composition which includes: (A) a polymer having double bonds between two carbons which is a copolymer of methyl methacrylate and 2-butenyl methacrylate, and (B) at least one aromatic aldehyde or aromatic ketone which absorbs ultraviolet rays of 300 to 400 nm wavelength and is benzophenone or 3-benzoyl-benzophenone; (2) irradiating the thin film in a regularly arranged pattern of ultraviolet rays, whereby compound (B) reacts with polymer (A) in the areas of irradiation; and (3) removing non-reacted compound (B), whereby a regularly pattern of irradiated areas having a greater thickness and a greater refractive index than areas not irradiated is realized.

Claim 14

A process for manufacturing a phase grating having combined pattern modification and refraction modification, comprising the steps of: (1) forming a thin film of composition which includes: (A) a polymer having double bonds between two carbons which is a copolymer of methyl methacrylate and geranyl methacrylate, and (B) at least one aromatic aldehyde or aromatic ketone which absorbs ultraviolet rays of 300 to 400 nm wavelength; (2) irradiating the thin film in a regularly arranged pattern of ultraviolet rays, whereby compound (B) reacts with polymer (A) in the areas of irradiation; and (3) removing non-reacted compound (B), whereby a regularly pattern of irradiated areas having a greater thickness and a greater refractive index than areas not irradiated is realized.

Claim 15

A process for manufacturing a phase grating having combined pattern modification and refraction modification, comprising the steps of: (1) forming a thin film of composition which includes: (A) a polymer having double bonds between two carbons which is a copolymer of methyl methacrylate and geranyl methacrylate, and (B) at least one aromatic aldehyde or aromatic ketone which absorbs ultraviolet rays of 300 to 400 nm wavelength; (2) irradiating the thin film in a regularly arranged pattern of ultraviolet rays, whereby compound (B) reacts with polymer (A) in the areas of irradiation; and (3) removing non-reacted compound (B), whereby a regularly pattern of irradiated areas having a greater thickness and a greater refractive index than areas not irradiated is realized.