Digitizing device

Claim 2

A digitizing device comprising means for generating three beams of light, means for spreading each beam to a fan-shaped beam, means for moving each fan-shaped beam through a working environment in a direction at right angles to the plane on each beam and at right angles to each other, light-sensitive means in said environment which gives rise to electrical signals when light is incident thereon, and positioning means responsive to the electrical signals to relate the position of the lightsensitive means in the environment to the relative positions of the light beams when striking the light-sensitive means during each sweep through the working environment.

Claim 3

A device according to claim 1 wherein each fan-shaped beam is reflected from a rotatable convex reflector which spreads a substantially cylindrical beam to the fan-shaped beam, rotation of the convex reflector causing the fan-shaped beam to sweep through the working environment.

Claim 4

A device according to claim 1 wherin the light-sensitive means comprises at least one detector having a translucent, spherical tip and a photosensitive semiconductor connected to the tip by a shielded light pipe, said semiconductor producing said electrical signals when light from one of the fan-shaped beams strikes the tip.

Claim 5

A device according to claim 1 wherein said positioning means includes three pairs of light-sensing elements each pair being associated with one of the fan-shaped beams and positioned adjacent the boundaries of the working environment to produce electrical pulsed signals when struck by the associated light beam but being shielded from the other light beams, said pairs of elements defining reference positions in relation to the working environment for the associated light beam.

Claim 6

A device according to claim 4 and further including a pair of counter means associated with each light beam, means for causing the counters of each pair to count at a constant rate, means for simultaneously starting both counters of each pair when the associated light beam strikes one of the light-sensing elements, means for stopping one of the light-sensing elements, means for stopping one of the counters of each pair when the associated light beam strikes the light-sensitive means and means for stopping the other of each pair when the associated light beam strikes the other of the associated light-sensing elements.

Claim 7

A device according to claim 5 further including means to reduce the counting rate of the other counter when the associated light beam is first incidenT on the light-sensitive means, and means to stop the first counter when the light beam is no longer incident thereon.

Claim 8

A device according to claim 1 wherein the light beams are generated by a laser.

Claim 9

A device according to claim 1 wherein two or more light beams sweep the working environment simultaneously or in sequence.

Claim 10

A device according to claim 1 further including a digital computer having means to plot digital coded co-ordinates of the light-sensitive means to determine the relative position thereof in the working environment for any number of sweeps of each of the light beams.

Claim 11

A digitizing device comprising means for generating at least one beam of light of circular cross-section, means for spreading each said beam to a fan shape, means to cause at least one of said fan-shaped beams, to sweep across a working environment from at least two directions; light-sensitive target means which gives rise to electrical signals when light is incident thereon; and means responsive to the electrical signals of the said light-sensitive target means to relate the position of said light-sensitive target means in the working environment to the relative position of the fan shaped light beams when striking light-sensitive reference means during each sweep thereof through the working environment.

Claim 12

A digitizing device comprising means for generating at least one beam of light of circular cross-section, means for spreading each said beam to a fan shape, means to cause at least one of said fan-shaped beams, to sweep across a working environment from at least two directions; light-sensitive target means which gives rise to electrical signals when light is incident thereon; and means responsive to the electrical signals of the said light-sensitive target means to relate the position of said light-sensitive target means in the working environment to the relative position of the fan shaped light beams when striking light-sensitive reference means during each sweep thereof through the working environment.

Claim 13

A device according to claim 10 wherein said means for causing the fan shaped light beam to sweep across the working environment comprises a rotatable reflector and two fixed reflectors located adjacent peripheral boundaries of the environment, means for directing the generated light beam onto the rotatable reflector which thereby causes the beam to sweep across the environment on rotation of the reflector, each said fixed reflectors further reflecting the rotating beam to cause additional sweeps of the beam across the environment on a single rotation of the rotatable reflector, characterised in that at least one of the rotatable reflector and the two fixed reflectors are of convex shape.

Claim 14

A device according to claim 11 wherein the light-sensitive target means comprises a detector pen having a part-spherical tip of translucent material, a light pipe connected to the tip and a photosensitive semiconductor on the other end of the light pipe and producing pulsed electrical signals when light from said beam is incident on the tip.

Claim 15

A device according to claim 12 wherein light- sensitive reference means, which give rise to electrical signals when struck by the said fan-shaped beam or beams, are positioned adjacent peripheral boundaries of the environment to define reference points to which the position of the light-sensitive target means is related through association of the movement of the said light beam sweeps between the said light-sensitive reference means and the respective electrical signals of the said light-sensitive reference means and the detector pen.

Claim 16

A device according to claim 13 and further including a pair of counters, means for supplying each counter simultaneously with an electrical pulse train, means for starting both counters when the said fan-shaped light beam sweeps past a reference position in the environment, means for stopping one of the counters when the light beam sweeps past a second reference position.

Claim 17

A device according to claim 14 further including electrical circuit means to slow the first counter to one half the counting rate of the second counter when the light beam is first incident on the detector pen tip and to stop the first counter when the light beam is no longer incident on the tip.

Claim 18

A device according to claim 15 wherein the rotatable reflector is caused to rotate at a substantially constant rate and a pulse train is generated by a master clock of a stable frequency.

Claim 19

A device according to claim 10 wherein any light beam is generated by a laser.

Claim 20

A digitizing device comprising means for generating at least one beam of light of circular cross-section; means to cause at least one of the bEams of light, to sweep across a working environment from at least two directions; light-sensitive target means which gives rise to electrical signals when light is incident thereon; and means responsive to the electrical signals of the light-sensitive means to relate the position of said means in the working environment to the relative position of the light beams during each sweep thereof through the working environment, and further including a pair of counters, means for supplying each counter simultaneiously with an electrical pulse train means for starting both counters when the light beam sweeps past a reference position in the environment, means for stopping one of the counters when the light beam sweeps past a second reference position, and further including electrical circuit means to slow the first counter to one-half the counting rate of the second counter when the light beam is first incident on the light-sensitive target means and to stop and first counter when the light beam is no longer incident on the said target means.

Claim 21

A digitizing device comprising means for generating at least one beam of light of circular cross-section; means to cause at least one of the bEams of light, to sweep across a working environment from at least two directions; light-sensitive target means which gives rise to electrical signals when light is incident thereon; and means responsive to the electrical signals of the light-sensitive means to relate the position of said means in the working environment to the relative position of the light beams during each sweep thereof through the working environment, and further including a pair of counters, means for supplying each counter simultaneiously with an electrical pulse train means for starting both counters when the light beam sweeps past a reference position in the environment, means for stopping one of the counters when the light beam sweeps past a second reference position, and further including electrical circuit means to slow the first counter to one-half the counting rate of the second counter when the light beam is first incident on the light-sensitive target means and to stop and first counter when the light beam is no longer incident on the said target means.

Claim 22

A device according to claim 18 wherein the light-sensitive target means comprises a detector pen having a part-spherical tip of translucent material, a light pipe connected to the tip and a photosensitive semiconductor on the other end of the light pipe and producing pulsed electrical signals when light from said beam is incident on the tip.

Claim 23

A device according to claim 18 wherein any light beam is generated by a laser.

Claim 24

A device according to claim 18 wherein a rotatable reflector is used to cause the beam to sweep across the working environment such reflector rotating at a substantially constant rate and wherein the said electrical pulse train is generated by a master clock of a stable frequency.