Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
79 words
A laser system for eroding a surface, comprising laser means and locating means for locating the surface accurately relative to an optical axis, the laser means being operable to deliver pulses of laser energy along the optical axis to a surface located by the said locating means to erode it, characterised in that the system further comprises means to control and vary the size of the area on the surface to which the pulses of laser energy are delivered.
Claim 2
Dependent Claim
79 words
A laser system for eroding a surface, comprising laser means and locating means for locating the surface accurately relative to an optical axis, the laser means being operable to deliver pulses of laser energy along the optical axis to a surface located by the said locating means to erode it, characterised in that the system further comprises means to control and vary the size of the area on the surface to which the pulses of laser energy are delivered.
Claim 3
Dependent Claim
28 words
A laser system according to claim l further comprising means to control and vary the shape of the area of the surface to which the pulses are delivered.
Claim 4
Dependent Claim
38 words
A laser system according to claim l or claim 2 in which variation of the size of the said area by the said means to control and vary does not substantially vary the energy density of the pulses.
Claim 5
Dependent Claim
138 words
A laser system according to any one of the preceding claims in which the said means to control and vary the size of the area on the surface to which the pulses are delivered comprises an optical system for receiving a laser beam provided by the laser means, for providing a region of divergence and/or a region of convergence of the beam and for subsequently collimating the beam, the said means to control and vary further comprising a beam- shaping stop means movable axially along the beam in a said region, the stop means having a beam-shaping window and/or a beam-shaping stop portion, whereby the proportion of the total beam cross-section which passes through the said window or strikes the said stop portion varies with movement of the stop means axially of the beam in the said region.
Claim 6
Dependent Claim
31 words
A laser system according to claim 4 which further comprises a further optical system to focus an image of the window or the stop portion on the surface to be eroded.
Claim 7
Independent Claim
102 words
A method of eroding a surface by laser energy in which: (a) a surface is located accurately relative to an optical axis along which a laser means is operable to deliver pulses of laser energy to the surface, and (b) the laser means is operated to deliver pulses of laser energy along the optical axis, characterised in that the size of the area on the surface to which the pulses are delivered is adjusted in a controlled manner prior to the delivery of the pulses of laser energy, thereby selecting the size of the area on the surface eroded by the pulses.
Claim 8
Independent Claim
102 words
A method of eroding a surface by laser energy in which: (a) a surface is located accurately relative to an optical axis along which a laser means is operable to deliver pulses of laser energy to the surface, and (b) the laser means is operated to deliver pulses of laser energy along the optical axis, characterised in that the size of the area on the surface to which the pulses are delivered is adjusted in a controlled manner prior to the delivery of the pulses of laser energy, thereby selecting the size of the area on the surface eroded by the pulses.
Claim 9
Dependent Claim
39 words
A method according to claim 6 in which the shape of the area on the surface to which the pulses are delivered is adjusted in a controlled manner thereby selecting the shape of the area eroded by the pulses.
Claim 10
Dependent Claim
35 words
A method according to claim 6 or claim 7 in which the size of the area to be eroded by said pulses is varied in a controlled manner during said step of operating the laser.
Claim 11
Dependent Claim
43 words
A method according to claim 6 or claim 7 in which following said step of adjusting the size of the area to be eroded the size of said area to be eroded is maintained substantially constant during said step of operating the laser.
Claim 12
Dependent Claim
31 words
l0. A method according to claim 8 in which the energy density of the pulses is maintained substantially constant during said variation of the size of the area to be eroded.