ULTRA HIGH PRECISION BEAM SPLITTING MIRROR LAWRENCE LIVERMORE NATIONAL LABS BERKELEY CALIFORNIA

Ultra high precision 1980s beam steering or beam splitting wedge mirror from Lawrence Livermore National Laboratories in Berkeley California. The wedge design and label “RW 2.45°” indicates the mirror is designed to deflect a light beam by 2.45 degrees. The glass is extremely flat, precision-ground — probably a λ/10 or better flatness (very high quality).

The gold/orange coating strongly suggests the mirror is designed for high-power laser applications — gold coatings are often used for infrared (IR) wavelengths, especially around 10.6 microns (CO₂ lasers).

Based on the construction of this mirror and the label attached to it, it may have been associated with LLNL’s Mirror Fusion Test Facility (MFTF) or its successor, MFTF-B. These facilities were significant projects in magnetic confinement fusion research during the late 1970s and 1980s. The MFTF-B, completed in 1986, was a large-scale experiment aiming to demonstrate the feasibility of tandem mirror fusion reactors.

The label on the mirror reads:

CUSTOMER: LLNL

P.O. # B064526

S.P.O. #82-16241

W.O. 89891 RW 2.45°

P/N: 87-107017-0A

PART NAME: MIRROR

SN# 03

The mirror is 8 inches in diameter, 1 3/4 inches thick, with one flat edge. It weighs 7 3/4 pounds.

Appears to be in excellent condition with no cracks or defects. In the original protective case. Untested and not guaranteed to meet any particular specifications. Offered as a collectible display item.