Prior art

Most Relevant Prior Art for US12240054B2

The analysis of prior art for US Patent 12240054B2 focuses on patents cited by the examiner, indicated by an asterisk (*) in the provided patent document, and those explicitly discussed in the "BACKGROUND" section of US12240054B2.

1. DE3833992C2

• Full Citation: DE3833992C2 - "LIGHT GUIDE AND RADIATION DEVICE", Assignee: Messerschmitt-Boelkow-Blohm Gmbh.
• Publication/Filing Date: Priority Date: 1988-10-06, Publication Date: 1992-03-19.
• Brief Description: This patent describes a method for achieving specific laser beam properties by coupling laser beams from two laser beam sources into a conventional optical fiber at different coupling angles. The resulting beam comprises various wavelengths selected to suit biological or medical processing tasks. The method can also employ a single laser source with a variable wavelength, where coupling conditions into the optical fiber depend significantly on the wavelength.
• Potential Anticipation (35 U.S.C. § 102): DE3833992C2 anticipates the general concept of modifying laser beam properties by coupling into an optical fiber. However, US12240054B2 distinguishes itself by utilizing a multi-clad fiber (specifically, a double-clad fiber) and selectively coupling laser beams into different cores (inner fiber core or outer ring core) to generate varying beam profile characteristics, potentially with a single wavelength. DE3833992C2's reliance on wavelength dependence and a conventional fiber does not disclose the specific multi-clad fiber structure or the selective core coupling mechanism required by independent claims 1 and 11 of US12240054B2. Specifically, claims 1 and 11 explicitly require "a multi-clad fiber having an inner fiber core and at least one outer ring core" and coupling "at least into the inner fiber core" or "at least into at least one outer ring core," which are not present in the teachings of DE3833992C2.

2. US5461692A

• Full Citation: US5461692A - "Multimode optical fiber coupling apparatus and method of transmitting laser radiation using same", Assignee: Amoco Corporation.
• Publication/Filing Date: Priority Date: 1993-11-30, Publication Date: 1995-10-24.
• Brief Description: This patent describes an apparatus and method for efficiently coupling and transmitting high-power laser radiation, particularly from a solid-state laser, through a multimode optical fiber. The invention focuses on matching the laser beam characteristics to the fiber's acceptance characteristics (numerical aperture and core diameter) to achieve efficient coupling and minimize losses. It also includes a lens system for focusing the beam into the fiber, emphasizing long-distance transmission of high-power laser radiation.
• Potential Anticipation (35 U.S.C. § 102): While US5461692A addresses the general coupling of laser radiation into an optical fiber for high-power transmission, it does not disclose the specific structure of a "multi-clad fiber having an inner fiber core and at least one outer ring core." Crucially, it does not teach the elective coupling of a single laser beam or different laser beams/sub-beams into distinct cores (inner vs. outer ring core) of such a multi-clad fiber to generate different beam profile characteristics as explicitly defined in claims 1 and 11 of US12240054B2. Its objective is efficient transmission, not the active manipulation and switching of output beam profiles via selective core engagement in a multi-clad fiber. Therefore, it does not anticipate the key structural and functional elements of claims 1 and 11.

3. JP3645013B2

• Full Citation: JP3645013B2 - "Optical transmission device, solid-state laser device, and laser processing device using them", Assignee: 三菱電機株式会社 (Mitsubishi Denki Kabushiki Kaisha).
• Publication/Filing Date: Priority Date: 1994-10-14, Publication Date: 2005-05-11.
• Brief Description: This patent describes an optical transmission device where a laser beam is introduced into an optical fiber via a condensing lens. The fiber includes a mode conversion optical fiber where light is guided through multiple cores, specifically mentioning a "main core" and a "sub-core (or ring core)". The invention teaches a method to switch between coupling into the main core or both cores to achieve different beam qualities, aiming to maintain beam quality even with a large diameter fiber and reduce fiber end damage.
• Potential Anticipation (35 U.S.C. § 102): JP3645013B2 is highly relevant as it explicitly discloses key elements of US12240054B2. It describes an optical fiber with "multiple cores" including a "main core" and a "sub-core (or ring core)," directly anticipating the "multi-clad fiber having an inner fiber core and at least one outer ring core" of claims 1 and 11. Furthermore, the method to "switch between coupling into the main core or both cores to achieve different beam qualities" strongly anticipates the selective coupling and generation of different beam profile characteristics central to US12240054B2. The primary point of distinction for US12240054B2's independent claims (Claims 1 and 11) might be the explicit requirement for "a first optical fiber configured to guide a first input laser beam to the multi-clad fiber; and a second optical fiber configured to guide a second input laser beam to the multi-clad fiber," and the coupling of these distinct input beams. While JP3645013B2 mentions "a laser beam is introduced," suggesting a single input being switched, it does not explicitly disclose the dual-fiber, dual-input laser beam arrangement.

4. US20060219673A1

• Full Citation: US20060219673A1 - "Apparatus for the industrial processing of a material by optical radiation", Assignee: Spi Lasers Uk Ltd.
• Publication/Filing Date: Priority Date: 2003-12-05, Publication Date: 2006-10-05.
• Brief Description: This patent application describes an apparatus for industrial material processing utilizing optical radiation, particularly a fiber laser. It features a laser source providing a primary beam and a separate auxiliary beam (or beams) that can be directed to a workpiece or into the same delivery fiber as the primary beam. The auxiliary beam can serve purposes like pre-heating, post-heating, or modifying the main beam's effect. It explicitly mentions using different cores of a multi-clad fiber for these different beams, such as the primary beam in a central core and the auxiliary beam in an outer cladding or ring. The intensity distribution of the combined output beam can be varied.
• Potential Anticipation (35 U.S.C. § 102): US20060219673A1 is highly anticipatory of US12240054B2. It describes an apparatus that includes a multi-clad fiber with different cores (e.g., central core, outer cladding/ring) for guiding distinct laser beams ("primary beam" and "auxiliary beam"). This directly anticipates the "multi-clad fiber having an inner fiber core and at least one outer ring core" of claims 1 and 11. Furthermore, the concept of coupling "different input laser beams into the different cores" to modify the combined beam's effect and vary its intensity distribution (and thus beam profile characteristics) aligns closely with the alternative embodiments described in US12240054B2 where "a first laser beam is coupled at least into the inner fiber core... and a different, second laser beam is coupled at least into one outer ring core." The specification also implies the use of two input sources that could be guided by optical fibers. This patent appears to anticipate the fundamental structural and functional aspects of claims 1 and 11, particularly concerning the use of multiple input beams into different cores of a multi-clad fiber to achieve variable output beam characteristics.