Rectangular Refraction Acrylic Block, 115 x 65 x 18mm Subcategory_Spectroscopy Hand-driven Newton's color disc that

Hand-driven Newton's color disc that spins seven painted segments fast enough to merge into apparent white through persistence-of-vision and additive color mixing

Adjustable iris from closed to a 30mm maximum aperture inside a 3-inch black metal body

5% accuracy on a 60mm scale

the moderate curvature spreading light gently for divergence and virtual-image-formation work in refraction demos

and PVC for comparative density and material-properties exploration

Rectangular Refraction Acrylic Block, 115 x 65 x 18mm Subcategory_Spectroscopy Hand-driven Newton's color disc thatMid size 115 by 65 by 18mm acrylic rectangular refraction block, the lightweight lab safe body matching glass block teaching geometry without the mass or fragility.