Improved optical interface for a magneto-optical current transducer

Claim 2

An optical interfacing device for communicat­ing a light signal to a light operative device, comprising: a spacer lens element receptive of such light signal; and characterized in that a collimator segment having a surface formed in the shape of a paraboloid of revolution is connected to said spacer lens segment and is effective such that, such light signal which enters said collimator segment as a divergent bundle of light, is focussed by a parabolic surface associated with said paraboloid of revolution into a parallel beam of light; and said spacer lens element and said collimator segment, when connected, form a collimating lens element having a monolithic configuration and which is connected to said light operative device such that said parallel beam of light is directed thereto.

Claim 3

An optical interfacing device as set forth in claim 1 further comprising a polarizing element connected between said light operative device and said collimating lens element such that, said parallel beam of light is polarized thereby.

Claim 4

An optical interfacing device as set forth in claim 1 wherein said collimating lens element has said parabolic surface formed at one end and a flat surface formed at the opposite end by an edge of said spacer lens element, which flat surface extends to the focal length of said parabolic surface.

Claim 5

An optical interfacing device as set forth in claim 3 wherein said focal length is selectively set so as to establish a specific diameter associated with said parallel beam of light.

Claim 6

An optical interfacing device as set forth in claim 2 wherein said polarizing element is connected to an edge of said light operative device at a right angle and said collimating lens element is connected to said polariz­ing element at a right angle, thereby providing that said collimating lens element is disposed parallel relative to said edge of said light operative device.

Claim 7

An optical interfacing device as set forth in claim 1 wherein said spacer lens element and said collimator segment are constructed of the same optical material and are secured in a surface-to-surface manner so as to eliminate any air gaps formed therebetween.

Claim 8

An optical interfacing device as set forth in claim 6 wherein said surfaces of said spacer lens element and said collimator segment are coated before connection such that, contamination of said surfaces is prevented.

Claim 9

An optical interfacing device as set forth in claim 1 wherein said collimator segment is formed by slicing a segment off of a parabolic lens element.

Claim 10

An optical interfacing device as set forth in claim 8 wherein said parabolic lens element has formed around the outer periphery thereof, a reference ring which, in the process of slicing said parabolic segment, is effective for establishing a center axis of said parabolic lens, said reference ring being essentially flat on the outer edge adjacent the parabolic surface of said parabolic lens element.

Claim 11

A magneto-optical current measuring device utilizing the optical interface device of claim 1 and effective for measuring the current in an energy transmis­sion line, comprising: a calibrated light source; a magneto-optical current sensing means disposed in surrounding proximity to said energy transmission line for imparting a change in planar orientation of a polarized beam of light as a function of a magnitude of current in said energy transmission line; and characterized in that, said collimator segment being receptive of the output of said calibrated light source and further being effective such that said calibrated light source output which enters said collimator segment element as a divergent beam of light, is focussed by a parabolic surface associated with said paraboloid of revolution into a parallel beam of light; a polarizing element connected between said collimator segment and said magneto-optical current sensing means and effective such that said parallel beam of light is polarized thereby; and, logic means connected to said magneto-optical current sensing means for evaluating said change in polar orientation of said polarized beam of light and determining therefrom, said magnitude of current.

Claim 12

A magneto-optical current measuring device as set forth in claim 10 wherein said magneto-optical current sensing means includes a Faraday rotator and further wherein said Faraday rotator has a collimating lens element and polarizing element disposed on one edge for inputting said polarized beam of light thereto, and a second collimating lens element and polarizing element disposed on an adjacent edge such that said logic means can be connected thereto.

Claim 13

A magneto-optical current measuring device as set forth in claim 11 wherein said Faraday rotator, said collimating lens elements, and said polarizing elements are constructed of the same optical material and are secured together in a surface-to-surface manner so as to eliminate any air gaps therebetween.

Claim 14

A magneto-optical current device as set forth in claim 10 wherein said collimator segment has said parabolic surface formed at one end and a flat surface formed at the opposite end by a surface of said spacer lens portion, which flat surface extends to the focal length of said parabolic surface.

Claim 15

A magneto-optical current measuring device as set forth in claim 11 wherein said Faraday rotator has associated therewith a cross-sectional area of specific dimension and further wherein said parallel beam of light has associated therewith a diameter preselectively estab­lished at a dimension substantially less than said cross-sectional dimension of said Faraday rotator.

Claim 16

A magneto-optical current measuring device as set forth in claim 10 wherein said collimating lens element and said polarizing element are aligned on said magneto-optical current sensing means by use of a visible wavelength light signal, and further wherein said collimating lens element and said polarizing element are secured to said magneto-optical current sensing means using an ultraviolet wavelength light signal and further, wherein said output of said calibrated light source is a light signal of an infrared wavelength at which wavelength said magneto-optical current sensing means is operative.