Conversion of circular dichroism spectropolarimeter to linear dichroism measurement mode

Claim 2

In a spectro-polarimeter having a source generating an electromagnetic radiation beam, a detector, the beam having a path extending between said source and detector, a linear polarizer in said path, and first converter means in said path to convert linearly polarized radiation from the linear polarizer to elliptically polarized radiation, the combination comprising: a. second converter means including a quarter-wave retarder in said path for converting elliptically polarized radiation from the first converter means to linearly polarized radiation, and b. means defining a sample space in the path of the linearly polarized beam passing from said second converter means, and c. said detector located to receive the linearly polarized radiation transmitted from the sample space.

Claim 3

The combination of claim 1 wherein said retarder has total internal reflection surfaces for intercepting said beam.

Claim 4

The combination of claim 1 wherein said retarder comprising a Fresnel rhomb.

Claim 5

The combination of claim 1 wherein said second converter means is characterized as located to operate upon the beam to alternate its polarization state between first and second linear states corresponding respectively to left and right circular states associated with said elliptically polarized radiation, said linear states having mutually orthogonal axes.

Claim 6

The combination of claim 4 including third converter means responsive to the beam passing from the second converter means to convert its polarization state to alternation between right and left circular.

Claim 7

The combination of claim 5, in which the third converter means is located to deflect the beam passing from the second converter means into coincidence with an optical axis defined by the beam passing through the first converter means.

Claim 8

The combination of claim 6 wherein said third converter means comprises a Fresnel rhomb.

Claim 9

In a spectropolarimeter having a source for generating an electromagnetic radiation beam, a detector, the beam having a path extending along an optical axis between said source and detector, a linear polarizer in said path, and first converter means in said path to convert linearly polarized radiation from the linear polarizer elliptically-polarized radiation, the combination comprising: a. second converter means including a quarter-wave retarder in the form of a Fresnel rhomb in said path for converting elliptically polarized radiation from the first converter means to linearly polarized radiation, b. means defining a sample space in the path of the beam passing from the rhomb, and c. mirror means located to deflect the optical axis of the beam passing from the rhomb into coincidence with that of the beam incident on the rhomb.

Claim 10

In a spectropolarimeter having a source for generating an electromagnetic radiation beam, a detector, the beam having a path extending along an optical axis between said source and detector, a linear polarizer in said path, and first converter means in said path to convert linearly polarized radiation from the linear polarizer elliptically-polarized radiation, the combination comprising: a. second converter means including a quarter-wave retarder in the form of a Fresnel rhomb in said path for converting elliptically polarized radiation from the first converter means to linearly polarized radiation, b. means defining a sample space in the path of the beam passing from the rhomb, and c. mirror means located to deflect the optical axis of the beam passing from the rhomb into coincidence with that of the beam incident on the rhomb.

Claim 11

In a spectropolarimeter having a source for generating an electromagnetic radiation beam, a detector, the beam having a path extending between the source and detector, a linear polarizer in said path, and first converter means in said path to convert linearly polarized radiation from the linear polarizer to elliptically-polarized radiation, the combination comprising: a. second converter means in said path extending from the first converter means for operating upon the beam to alternate its polarization state between first and second linear states corresponding respectively to left and right circular states associated with said elliptically polarized radiation, said linear states having mutually orthogonal axes, b. third converter means responsive to the beam passing from the second converter means to convert its polarization state to alternation between right and left circular, and c. means defining a sample space located in the path of the beam passing between said second and third converter means.

Claim 12

In a spectropolarimeter having a source for generating an electromagnetic radiation beam, a detector, the beam having a path extending between the source and detector, a linear polarizer in said path, and first converter means in said path to convert linearly polarized radiation from the linear polarizer to elliptically-polarized radiation, the combination comprising: a. second converter means in said path extending from the first converter means for operating upon the beam to alternate its polarization state between first and second linear states corresponding respectively to left and right circular states associated with said elliptically polarized radiation, said linear states having mutually orthogonal axes, b. third converter means responsive to the beam passing from the second converter means to convert its polarization state to alternation between right and left circular, and c. means defining a sample space located in the path of the beam passing between said second and third converter means.

Claim 13

The combination of claim 9 including another sample space located in the path of the beam passing between the first and second converter means.

Claim 14

The combination of claim 10 including a further sample space located in the path of the beam passing from the third converter means.

Claim 15

The combination of claim 11 including samples in said spaces between the first and second converter means and following the third converter means.

Claim 16

In a spectropolarimeter having a source for generating an electromagnetic radiation beam, a detector, the beam having a path between said source and detector, and a linear polarizer in said path, the combination comprising a. first and second converter means located in said path so that the beam passes through the second converter means prior to passage through the first converter means, b. The first converter means responsive to incident linearly polarized radiation to produce elliptically-polarized radiation, and the second converter means responsive to incident elliptically polarized radiation to produce linearly polarized radiation, the linear polarizer located in the path between the first converter means and the detector, and c. means defining a sample space in the path of the beam passing between the source and the second converter means.

Claim 17

In a spectropolarimeter having a source for generating an electromagnetic radiation beam, a detector, the beam having a path between said source and detector, and a linear polarizer in said path, the combination comprising a. first and second converter means located in said path so that the beam passes through the second converter means prior to passage through the first converter means, b. The first converter means responsive to incident linearly polarized radiation to produce elliptically-polarized radiation, and the second converter means responsive to incident elliptically polarized radiation to produce linearly polarized radiation, the linear polarizer located in the path between the first converter means and the detector, and c. means defining a sample space in the path of the beam passing between the source and the second converter means.