Home▸Forensic Toxicology & Analytical Chemistry▸Glass Refractive Index Matching (GRIM) — 2D Hot-Stage Lab

Glass Refractive Index Matching (GRIM) — 2D Hot-Stage Lab

Interactive 2D glass refractive-index-matching simulator: heat a silicone immersion oil on a virtual hot stage until its index matches a forensic glass fragment and the Becke line vanishes, with a live n(T) graph and a Snell's-law ray diagram showing exactly why the halo moves -- the real GRIM technique used to compare crime-scene glass to a suspect's.

Forensic Toxicology & Analytical Chemistry2DModerate60 FPS📱 Mobile-adapted⇄ 3D version

A real glass fragment sits in a droplet of silicone immersion oil on a heated microscope stage. Choose a forensic glass type, then heat the oil and watch the refractive-index mismatch — and the bright Becke line tracing the fragment's edge — shrink toward zero exactly where the oil's index crosses the glass's own index. A live dispersion graph tracks n(oil) against n(glass) as you heat the stage, and a Snell's-law ray diagram shows the actual refraction that produces the halo. This is the real GRIM technique crime labs use to compare trace glass evidence, right down to the rule that raising the objective sends the Becke line into whichever medium has the higher index.

⚙ Under the hood

Heat a silicone immersion oil on a simulated hot stage until its refractive index matches a forensic glass fragment and the Becke line disappears -- with a live n(T) dispersion graph and a Snell's-law ray diagram that shows exactly why the halo shifts sides, the real GRIM technique crime labs use to compare trace glass evidence.

forensicsopticsrefractive indexglass analysistrace evidenceGRIMsnell's law

2D · HTML5 Canvas 2D · 60 FPS target · runs fully client-side, no install