B&L 7x50 Wide Field Mark41
Mfr: Bausch & Lomb, Rochester, USA
Date: WWII
AFOV: 70 degrees
Eye Relief: ~20mm
The B&L 7x50 Wide Field is perhaps the most impressive American handheld binocular ever made. Its combination of such a wide field and comfortable eye relief is only found in one other American binocular from WWII (to my knowledge), the Sard 6x42. The B&L 7x50 WF has the advantage of a higher power than the Sard. Commercially marked versions of the B&L 7x50 WF were sold after WWII. The Mark 41 was originally issued with a large rubber eyeshield shown in one of the pictures below. Also shown below is the rubber case for the Mark 41 made by Hood, and the inscription inside the case.
The prisms in the B&L 7x50 WF are approximately 30mmx60mm, much larger than normal in order to capture more of the light for the wide field. A prism cluster attached to the eyepiece is shown below, and also an inside view of the body with the prisms removed. The one piece construction of the prisms and eyepiece allows easy servicing.
Wooden shims were used under the prism clamps. A fault commonly found with the B&L 7x50 WF is the loosening of the prisms when the little bits of wood dry out. This can be fixed by replacing the shims with thin pieces of rubber or similar material.