Post Mounting Angle Blocks
- Angle Blocks for Ten Discrete Angles from 4° to 54.7°
- 8-32 (M4) Tapped Hole or #8 (M4) Counterbore on Top
- Ø1/2" and Ø1" (Ø25 mm) Post Mountable
- 35.3° and 54.7° Angle Blocks for Magic Angle Pump-Probe Experiments
#8 (M4) Counterbore
8-32 (M4) Tapped Hole
8-32 (M4) Tapped Hole
Application Idea
KS05 Mirror Mount on an AM16C 16° Angle Block
AM16C
16°
AM8T
8°
AM353T
35.3º (Magic Angle)
Please Wait
Click to Enlarge This photo shows a GL15-B Glan-Laser Polarizer secured to a KM100B Platform Mount by a PM3 Clamping Arm. The AM353T Angle Block helps orient the polarizer at a 35.3° angle.
Our Angle Blocks can be used to orient mirror mounts and other optomechanics at several fixed angles from 4° to 54.7°. They are available with either an 8-32 (M4) tap on top or a #8 (M4) counterbore on top. The bottom of the angle block has an 8-32 (M4) tapped hole for our Ø1/2" and Ø1" (Ø25 mm) posts. They are manufactured from black-anodized aluminum and are engraved with the part number for easy identification of the angle.
Additionally, Thorlabs offers an adjustable flip platform with tick marks engraved in 15° increments which can be used to hold components fixed at various angles.
Application Note: The Magic Angle
Our 35.3° and 54.7° angle blocks are designed to help orient polarizers in rectangular housings, such as Glan-Laser polarizers, at the magic angle used in certain ultrafast pump-probe measurements. In this family of experiments, which includes fluorescence lifetime measurements, transient absorption spectroscopy, and vibrational spectroscopy, it is advantageous to polarize the probe beam at the magic angle of 54.7° (relative to the pump beam's polarization). This angle makes the probe beam insensitive to unwanted anisotropies that would otherwise be convolved with the measured signal.
When using Thorlabs' Glan-Laser polarizers, we recommend securing the polarizer to a Kinematic Platform Mount, as shown in the photo to the right. The kinematic mount enables fine angle tuning and leaves a large clear edge around the polarizer, making it easier to maintain overlap of the pump and probe beams through the sample. In the photo, a 35.3° angle block is used, which requires the pump beam to be vertically polarized; this configuration allows the clamping arm to avoid touching the sides of the housing that have escape windows.
For ultrafast experiments, Thorlabs also offers optical delay line kits, as well as low-GDD dielectric mirrors.
Posted Comments: | |
Hyeokjin Cho
 (posted 2022-10-25 13:42:44.923) It would be useful if both sides are counterbore. It can be used for more general purpose (post mounting still available through M4 bolt). ksosnowski
 (posted 2022-10-25 03:09:23.0) Thanks for reaching out to Thorlabs. I am adding this insight to our forum for internal development. This is an interesting idea as it could also allow the part to be used universally with metric or imperial hardware. tmagnan2
 (posted 2015-07-08 16:59:21.183) For ultrafast measurements/applications, having a block like one of these set to magic angle and/or its complement (54.7 or 35.3 deg.) would be rather useful. It would serve as an efficient and economic way to set the angle of a polarizer to eliminate the effects of polarization anisotropy. Just a thought, thanks! besembeson
 (posted 2015-09-23 10:03:22.0) Response from Bweh at Thorlabs USA: Thanks for the feedback. We will review this. bdada
 (posted 2012-02-13 19:04:00.0) Response from Buki at Thorlabs to acable:
Thank you for participating in our feedback forum. You raise a valid point and we have passed this on to our production team. Depending on what you want to mount at 45 degrees, there may be a few alternative solutions for you to consider in the short term:
1. MA45-2 - 45° Mounting Adapter, on which you can mount our KM100 or KM200 mirror mount
2. H45B2 - 45° Optic Holder for 1" diameter optics
The product page below has more information on these products:
http://www.thorlabs.com/NewGroupPage9.cfm?ObjectGroup_ID=785 acable
 (posted 2012-02-13 12:46:41.0) Seems like you stopped short of the most useful angle, can you add a 45 degree design. bdada
 (posted 2012-02-02 19:12:00.0) Response from Buki at Thorlabs:
Thank you for participating in our feedback forum. The angle blocks are made from aluminum, which is non-magnetic. This information is included in the bottom right corner of the drawing linked below:
http://www.thorlabs.com/Thorcat/22200/22297-E0W.pdf shane
 (posted 2012-02-02 17:14:37.0) Could you tell me what materials are used in these? We have an application for which we need non-magnetic parts. Thanks. |
- Top Surface has an 8-32 (M4) Tapped Hole for Attaching Optomechanical Components
- Bottom Surface has an 8-32 (M4) Tapped Hole
- 4°, 8°, 16°, 24°, 30°, 32°, 35.3°, 40°, 45°, and 54.7° Versions Available
These Angle Blocks contain an 8-32 (M4) tapped hole that is designed to mate with optomechanical components that have a counterbored mounting hole, such as our Kinematic Platform Mounts and most of our Kinematic Mirror Mounts. The bottom of the angle block has an 8-32 (M4) tapped hole for post mounting.
- Top Surface has a #8 (M4) Counterbore for Attaching Optomechanical Components
- Bottom Surface has an 8-32 (M4) Tapped Hole for Posts
- 4°, 8°, 16°, 24°, 30°, 32°, 35.3°, 40°, 45°, and 54.7° Versions Available
These Angle Blocks contain a #8 (M4) counterbore that is designed to mate with optomechanical components that have a tapped mounting hole, such as our KM05(/M) Ø1/2" Kinematic Mirror Mount and Fixed Lens Mounts. The bottom of the angle block has an 8-32 (M4) tapped hole for post mounting.