Faraday rotator device including lithia-silicate glass articles containing Tb2 O3 and methods of using same

Claim 2

A Faraday rotator device comprising 1. means for supplying polarized electromagnetic radiation, 2. a glass article capable of effecting Faraday rotation when subjected to a magnetic field, and 3. magnetic means for inducing a magnetic field in the glass article for rotating the polarized electromagnetic radiation within the glass, said glass article having a high Verdet constant, having good light transmission, having good melt properties, having a high damage threshold, having good forming properties including a relatively wide working temperature at approximately log 4 viscosity, being relatively seed-free and being easily homogenized, said glass having a composition approximately as follows: INGREDIENTS MOLE PERCENT ______________________________________ SiO.sub.2 61-80 Li.sub.2 O 15-27.5 Na.sub.2 O 0-10 K.sub.2 O 0-5 CaO 0-5 Al.sub.2 O.sub.3 0-3 B.sub.2 O.sub.3 0-3 La.sub.2 O.sub.3 0-3 Tb.sub.2 O.sub.3 3-9 ______________________________________ wherein the sum of Li 2 O + Na 2 O + K 2 O + CaO is no greater than about 32.5 mole percent.

Claim 3

A device as defined in claim 1 in which the composition of the glass is approximately as follows: INGREDIENTS MOLE PERCENT ______________________________________ SiO.sub.2 61-71 Li.sub.2 O 20-27.5 Na.sub.2 O 0-5 K.sub.2 O 0-3 CaO 0-3 Al.sub.2 O.sub.3 0-3 B.sub.2 O.sub.3 0-3 Tb.sub.2 O.sub.3 7-9. ______________________________________

Claim 4

A device as defined in claim 1 in which the glass composition is approximately as follows: INGREDIENTS MOLE PERCENT ______________________________________ SiO.sub.2 61 Li.sub.2 O 27.5 Al.sub.2 O.sub.3 2.5 Tb.sub.2 O.sub.3 9. ______________________________________

Claim 7

A method as defined in claim 4 in which the glass composition is approximately as follows: INGREDIENTS MOLE PERCENT ______________________________________ SiO.sub.2 61-71 Li.sub.2 O 20-27.5 Na.sub.2 O 0-5 K.sub.2 O 0-3 CaO 0-3 Al.sub.2 O.sub.3 0-3 B.sub.2 O.sub.3 0-3 Tb.sub.2 O.sub.3 7-9. ______________________________________

Claim 8

A method as defined in claim 4 in which the glass article has a composition approximately as follows: INGREDIENTS MOLE PERCENT ______________________________________ SiO.sub.2 61 Li.sub.2 O 27.5 Al.sub.2 O.sub.3 2.5 Tb.sub.2 O.sub.3 9. ______________________________________

Claim 9

The new use for a glass article in which the glass has a composition approximately as follows: INGREDIENTS MOLE PERCENT ______________________________________ SiO.sub.2 61-80 Li.sub.2 O 15-27.5 Na.sub.2 O 0-10 K.sub.2 O 0-5 CaO 0-5 Al.sub.2 O.sub.3 0-3 B.sub.2 O.sub.3 0-3 La.sub.2 O.sub.3 0-3 Tb.sub.2 O.sub.3 3-9 ______________________________________ wherein the sum of Li 2 O + Na 2 O + K 2 O + CaO is no greater than about 32.5 mole percent, the new use comprising the steps of 1. placing the glass article in a magnetic field, and 2. directing polarized electromagnetic radiation into the glass article for effecting Faraday rotation of the radiation.

Claim 10

The new use for a glass article in which the glass has a composition approximately as follows: INGREDIENTS MOLE PERCENT ______________________________________ SiO.sub.2 61-80 Li.sub.2 O 15-27.5 Na.sub.2 O 0-10 K.sub.2 O 0-5 CaO 0-5 Al.sub.2 O.sub.3 0-3 B.sub.2 O.sub.3 0-3 La.sub.2 O.sub.3 0-3 Tb.sub.2 O.sub.3 3-9 ______________________________________ wherein the sum of Li 2 O + Na 2 O + K 2 O + CaO is no greater than about 32.5 mole percent, the new use comprising the steps of 1. placing the glass article in a magnetic field, and 2. directing polarized electromagnetic radiation into the glass article for effecting Faraday rotation of the radiation.

Claim 11

The new use as defined in claim 7 in which the electromagnetic radiation is plane polarized.

Claim 12

The new use as defined in claim 7 in which the electromagnetic radiation is circularly polarized.

Claim 13

The new use as defined in claim 7 in which the electromagnetic radiation is eliptically polarized.

Claim 14

A Faraday rotator device comprising a source of light for providing a monochromatic light beam, light polarizing means for polarizing the monochromatic light beam to provide a monochromatic polarized light beam, a glass article capable of effecting Faraday rotation of the monochromatic polarized light beam when subjected to a magnetic field, and magnetic means for inducing a magnetic field for rotating the polarized monochromatic light beam within the glass article, said glass article having a high Verdet constant, good light transmission, good melt properties, high damage threshold, good forming properties including a relatively wide working temperature at approximately log 4 viscosity, being relatively seed-free and being easily homogenized, the glass having a composition approximately as follows INGREDIENTS MOLE PERCENT ______________________________________ SiO.sub.2 61-80 Li.sub.2 O 15- 27.5 Na.sub.2 O 0-10 K.sub.2 O 0-5 CaO 0-5 Al.sub.2 O.sub.3 0-3 B.sub.2 O.sub.3 0-3 La.sub.2 O.sub.3 0-3 Tb.sub.2 O.sub.3 3-9. ______________________________________ wherein the sum of Li 2 O + Na 2 O + K 2 O + CaO is no greater than about 32.5 mole percent.

Claim 15

A Faraday rotator device comprising a source of light for providing a monochromatic light beam, light polarizing means for polarizing the monochromatic light beam to provide a monochromatic polarized light beam, a glass article capable of effecting Faraday rotation of the monochromatic polarized light beam when subjected to a magnetic field, and magnetic means for inducing a magnetic field for rotating the polarized monochromatic light beam within the glass article, said glass article having a high Verdet constant, good light transmission, good melt properties, high damage threshold, good forming properties including a relatively wide working temperature at approximately log 4 viscosity, being relatively seed-free and being easily homogenized, the glass having a composition approximately as follows INGREDIENTS MOLE PERCENT ______________________________________ SiO.sub.2 61-80 Li.sub.2 O 15- 27.5 Na.sub.2 O 0-10 K.sub.2 O 0-5 CaO 0-5 Al.sub.2 O.sub.3 0-3 B.sub.2 O.sub.3 0-3 La.sub.2 O.sub.3 0-3 Tb.sub.2 O.sub.3 3-9. ______________________________________ wherein the sum of Li 2 O + Na 2 O + K 2 O + CaO is no greater than about 32.5 mole percent.

Claim 16

A device as defined in claim 11 in which there is provided analyzing means for analyzing the rotated polarized monochromatic light beam that travels through the glass article.

Claim 17

A device as defined in claim 12 in which the glass composition has the following approximate formulation: INGREDIENTS MOLE PERCENT ______________________________________ SiO.sub.2 63.5 Li.sub.2 O 27.5 Tb.sub.2 O.sub.3 9. ______________________________________

Claim 18

A device as defined in claim 1 in which the glass has the approximate composition as follows: INGREDIENTS MOLE PERCENT ______________________________________ SiO.sub.2 61 Li.sub.2 O 27.5 Al.sub.2 O.sub.3 2.5 Tb.sub.2 O.sub.3 9. ______________________________________

Claim 19

A device as defined in claim 1 in which the glass has a composition approximately as follows: INGREDIENTS MOLE PERCENT ______________________________________ SiO.sub.2 61-80 Li.sub.2 O 15-27.5 Tb.sub.2 O.sub.3 3-9. ______________________________________

Claim 20

A device as defined in claim 1 in which the glass has a composition approximately as follows: INGREDIENTS MOLE PERCENT ______________________________________ SiO.sub.2 61- 71 Li.sub.2 O 20- 27.5 Tb.sub.2 O.sub.3 7- 9. ______________________________________

Claim 21

A device as defined in claim 1 in which the glass has a composition approximately as follows: INGREDIENTS MOLE PERCENT ______________________________________ SiO.sub.2 63.5 Li.sub.2 O 27.5 Tb.sub.2 O.sub.3 9. ______________________________________

Claim 22

A method as defined in claim 4 in which the glass has a composition approximately as follows: INGREDIENTS MOLE PERCENT ______________________________________ SiO.sub.2 61-80 Li.sub.2 O 15-27.5 Tb.sub.2 O.sub.3 3-9. ______________________________________

Claim 23

A method as defined in claim 4 in which the glass has a composition approximately as follows: INGREDIENTS MOLE PERCENT ______________________________________ SiO.sub.2 61-71 Li.sub.2 O 20-27.5 Tb.sub.2 O.sub.3 7-9. ______________________________________

Claim 24

A method as defined in claim 4 in which the glass has a composition approximately as follows: INGREDIENTS MOLE PERCENT ______________________________________ SiO.sub.2 63.5 Li.sub.2 O 27.5 Tb.sub.2 O.sub.3 9. ______________________________________

Claim 25

The new use as defined in claim 7 in which the glass has the approximate composition as follows: INGREDIENTS MOLE PERCENT ______________________________________ SiO.sub.2 61 Li.sub.2 O 27.5 Al.sub.2 O.sub.3 2.5 Tb.sub.2 O.sub.3 9. ______________________________________

Claim 26

The new use as defined in claim 7 in which the glass has the approximate composition as follows: INGREDIENTS MOLE PERCENT ______________________________________ SiO.sub.2 63.5 Li.sub.2 O 27.5 Tb.sub.2 O.sub.3 9. ______________________________________