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How do enantiomers affect plane-polarized light differently?

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Two diagrams show the three-dimensional structure of a methane molecule: panel A uses a ball-and-stick model with a central carbon atom connected to four hydrogen atoms in a tetrahedral arrangement, while panel B illustrates the bond angle of 109.5 degrees and bond length of 1.09 angstroms between carbon and hydrogen atoms. — isomerism Tetrahedral geometry of methane: (A) stick-and-ball model and (B) diagram showing bond angles and distances. (Plain bonds represent bonds in the plane of the image; wedge and dashed bonds represent those directed toward and away from the viewer, respectively.)

Enantiomers are pairs of molecules that are non-superimposable mirror images of each other, similar to a person's left and right hands. While they share identical physical and chemical properties in most environments, they interact differently with plane-polarized light, a phenomenon known as optical activity.123

When a beam of plane-polarized light passes through a solution containing one of these enantiomers, the molecule rotates the plane of polarization. The two enantiomers in a pair will rotate the plane by the exact same magnitude, but in opposite directions:432

Dextrorotatory (+ or d): The enantiomer rotates the plane of polarized light to the right (clockwise).43
Levorotatory (- or l): The enantiomer rotates the plane of polarized light to the left (counterclockwise).43

This ability to rotate light is a key method used in polarimetry to distinguish between enantiomers and determine the purity of a substance. Because their interaction with polarized light is opposite, a mixture containing equal amounts of both enantiomers (a racemic mixture) will result in zero net rotation of the light.532