Custom Fiber Laser Quartz End Caps

Parameter	Typical Range
Fiber bore / fit	125–400 µm, matched to fiber cladding OD
OD	0.4–3 mm
Length	0.5–5 mm
End-face angle	0° (perpendicular) standard; angled (e.g. 8°) on request
End-face flatness	λ/4 to λ/10 @ 633 nm
Surface quality	20/10 to 10/5 Scratch-Dig
Concentricity	±2–5 µm

Inquiry

Quartz end caps fusion-spliced or bonded to fiber ends to expand the beam before it exits — sized to your fiber and finished to the end-face angle your assembly needs.

Fiber bore/fit, OD, and end-face spec move together — a tight fiber fit at a small OD limits how much end-face polishing margin is left before the cap gets too thin near the edge. Confirm fiber OD alongside cap OD and length.

Available Fiber Laser Quartz End Caps Configurations

End caps come as either a solid rod fused directly to the fiber end, or a short capillary-bore piece the fiber slides into before fusing — tell us which your splicing process uses, since it changes whether "bore" refers to a fiber-fit hole or the cap is solid stock.

Fiber Bore, Taper and End-Face Options

A straight bore or solid rod is standard; a tapered transition from fiber OD up to cap OD is available where the assembly needs a gradual mode-field expansion rather than a step change. End-face angle matters for back-reflection control — a perpendicular face is standard, an angled face (commonly around 8°) reduces reflections back into the fiber for high-power systems.

Fiber Laser Quartz End Caps Factory Standard & Manufacturing Limit

The table above is what's repeatable without added lead time. Bore tolerance, concentricity, and OD tolerance all tighten together at small sizes — pushing one to its limit generally means the other two need confirming too, not assumed.

End-Cap Geometry for Fiber Laser Assemblies

Length is short by design, and even a small end-face flatness deviation matters more here than on a longer optic, since there's little material to average it out over. Chamfer at the OD edge is standard to prevent chipping during handling and splicing; it doesn't affect the optical end-face itself.

1064 nmAR Reference Band

1090 nmAR Reference Band

3Optical Quote Levels

Straight / WedgeEnd-Face Options

Bore + ODAlignment Datums

SyntheticFused Silica Option

Fiber Interface

Define the Bore Axis Before the Optical End Face

Controlled Feature	Reference Capability / Requirement
Material	Synthetic fused silica selected for transmission, homogeneity and laser service
Outer Diameter / Length	Matched to the ferrule, holder or splice assembly drawing
Fiber Bore	Diameter and depth specified from the fiber and joining process
Bore Tolerance	Controlled against insertion, splice and alignment requirements
Concentricity	Bore axis referenced to the outside diameter or optical axis
End-Face Angle	Normal, angled or wedged face defined by the optical design
Surface Quality / Figure	Specified over the clear optical area
AR Coating	1064 nm, 1090 nm or a custom working band; angle of incidence must be stated

Optical Levels

Three Reference Grades for Quoting

Level	Surface / Figure	Angle / Size	Typical Use
Standard	80/50 · 5λ	3′ · ±0.2 mm	Mechanical protection and development assemblies
Precision	60/40 · 1λ	1′ · ±0.1 mm	Fiber delivery and amplifier assemblies
Ultra	40/20 · λ/4	30″ · ±0.05 mm	Alignment-sensitive high-power laser interfaces

Available Forms

End-Cap Geometry Options

Straight End CapParallel body for standard holder and splice arrangements

Wedged End FaceControlled exit angle used to manage back reflection

Tapered TransitionReduced fiber-side section transitioning to a larger optical aperture

Bored End CapPrecision bore aligned to the outside diameter and polished face

Applications

Fiber-Laser Integration

High-Power Fiber LasersExpanded exit aperture at the fiber termination

Fiber AmplifiersControlled bore alignment and wavelength-specific end-face coating

Beam-Combining AssembliesCustom geometry matched to multi-component optical packages

Laser DevelopmentPrototype end caps for splice, coating and thermal trials

Need an end cap matched to your fiber and working wavelength?Send fiber diameter, bore depth, OD, length, end-face angle, coating band, clear aperture and inspection level.

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Engineering Data