TRF90/M

• Designed to hold Ø1" (25–25.4 mm) round optics.
• Provides a convenient 90° flip motion for quickly moving an optic into or out of the optical path.
• Detent positions at 0° and 90° provide positive positioning.
• Can be locked at any angle between 0° and 90° using the integrated nylon-tipped setscrews.
• <25 µrad angular repeatability at the 0° and 90° positions.
• M4 mounting thread for metric optical posts and bases.
• Can be post-mounted individually.
• Can also be rod-mounted for stacking multiple flip mounts.
• Compact design for easy integration into optical setups.
• Includes one retaining ring for securing the optic.
• Suitable for frequently changing filters and optical components during experiments.

The Thorlabs TRF90/M is a compact 90° flip mount designed for Ø1" (25–25.4 mm) filters and optical components. It provides a fast and convenient way to insert an optic into the beam path or move it completely out of the way without removing the optic from the optical setup.

The mount uses a precision detent mechanism that provides holding force at both the 0° and 90° positions. This allows users to quickly switch between two defined positions—for example, placing a bandpass filter into the beam path for measurement and then flipping it away when the filter is not required.

For applications requiring an intermediate position, the integrated nylon-tipped setscrews allow the mount to be locked at any angle between 0° and 90°. This provides additional flexibility when the optic needs to be positioned at a specific angle rather than simply inserted or removed from the beam.

The TRF90/M can be post-mounted as an individual component, or ER-rod-mounted for stacking multiple mounts in series. This makes it useful for optical systems containing several filters that need to be independently introduced into the beam path.

The mount is also used in a variety of research optical systems, including microscopy and photonics setups, where multiple filters or optics need to be rapidly switched during experiments.

Product Type: 90° Flip Mount
Part Number: TRF90/M
Optic Diameter: Ø1" / Ø25–25.4 mm
Optic Type: Round Filters and Optics
Flip Range: 0°–90°
Detent Positions: 0° and 90°
Angular Repeatability: <25 µrad at 0° and 90°
Mounting Thread: M4
Optic Retention: Retaining Ring
Mounting Options: Post-Mounted / ER-Rod-Mounted
Locking: Lockable at Any Angle from 0°–90°
Design: Stackable
Primary Function: Rapid Insertion/Removal of Optics

Thorlabs specifies the TRF90/M as the metric version of the TRF90 and lists it as a 90° flip mount for Ø1" filters and optics with an M4 tap.

The TRF90/M is suitable for:

• Optical Filter Mounting
• Bandpass Filter Switching
• Neutral Density Filter Switching
• Laser Beam Filtering
• Laser Beam Alignment
• Optical Path Selection
• Spectroscopy
• Microscopy
• Fluorescence Imaging
• Photonics Research
• Quantum Optics
• Laser Experiments
• Optical Instrumentation
• Beam Shaping
• Laboratory Optical Setups
• Educational Optical Experiments

Typical Applications

1. Quick Filter Switching
Install a bandpass or neutral-density filter in the TRF90/M and flip it into the beam whenever required.

2. Optical Path Alignment
Use the flip mechanism to temporarily remove an optic from the beam path without disturbing its alignment.

3. Multiple Filter Systems
Several TRF90/M mounts can be stacked using compatible cage rods, allowing multiple filters to be independently inserted into the same optical path.

4. Research & Prototyping
Particularly useful when an optical experiment requires frequent changes between different filters, lenses, or other Ø1" optics.