Wavelength-selective laser beam splitter

• US 6,661,577 B1
• Filed: 09/17/2002
• Issued: 12/09/2003
• Est. Priority Date: 09/17/2002
• Status: Expired due to Term

• Current Assignee: Lumentum Operations, LLC (Lumentum Holdings Inc.)
• Original Assignee: Viavi Solutions, Inc. (Lumentum Holdings Inc.)
• Inventors: Lin, Yinglong, Wu, Li
• Primary Examiner(s): Mack, Ricky
• Application Number:
  US10/244,631
• Time in Patent Office: 448 Days
• Field of Search: 359/618, 359/640, 359/494, 359/495, 359/496, 359/485
• US Class Current: 359/619
• CPC Class Codes: G02B 27/1006 for splitting or combining different wavelengths G02B27/1086, G02B27/141 take precedence
• CPC Class Codes: G02B 27/12 operating by refraction only

Abstract

A beam splitting device for laser field is useful to spatially separate a laser beam created in the process of frequency doubling or three-wave mixing, into sub-beams according to wavelength and polarization state. The device has an optical retarder for wavelength-selective polarization rotation of the laser light, followed by a Wollaston prism and optionally a dual wedge prism to create parallel spatially separated sub-beams. Alternatively, two Wollaston prisms can be arranged to create two parallel spatially separated beams after the polarization rotation.

Claims

1. A laser beam splitting device for spatially separating a laser light beam having two or more wavelengths, the device comprising:

a wavelength-selective polarization rotating means disposed in the path of the laser light beam having two or more wavelengths for imparting a different polarization direction to different wavelengths of the light beam thus forming two or more sub-beams of light having a different polarization characteristics, and

a means disposed in the path of the sub-beams of light for spatially separating the sub-beams of light according to their polarization characteristics.

2. The device of claim 1 further comprising directional means disposed to receive the spatially separated sub-beams and to direct them into spatially separated substantially parallel paths.

3. The device of claim 1 wherein the wavelength-selective means is a wavelength-specific half-waveplate.

4. The device of claim 1 wherein the wavelength-selective means is an interleaver.

5. The device of claim 1 wherein the means for spatially separating the sub-beams comprise a walk-off crystal disposed to angularly separate the differently polarized sub-beams of light.

6. The device of claim 1 wherein the spatially separating means is a Wollaston prism.

7. The device of claim 1 wherein the spatially separating means is a walk-off crystal.

8. The device of claim 4 wherein the spatially separating means is a walk-off crystal.

9. The device of claim 2 wherein the directional means is a Wollaston prism.

10. The device of claim 2 wherein the directional means is a dual wedge prism.

11. The device of claim 1 wherein the wavelength-selective polarization rotating means is selected to correct for an angle between polarization states of the laser light beam.

12. A device of claim 1 wherein the laser light beam comprises two or more wavelengths of which at least one has a different polarization state than another wavelength, the device comprising, before the wavelength-selective polarization rotating means, a means for separating the laser light beam into sub-beams having each one polarization state, such that a selected sub-beam with two or more wavelengths and one polarization state is directed to the wavelength-selective polarization rotating means.