Uses Gaussian formula: 1/f = 1/u + 1/v. Objects beyond 2f create reduced real images, between f and 2f create magnified real images, and inside f create virtual images.
Concave Lens
Always produces upright, reduced virtual images. Light rays diverge as if coming from a virtual focal point.
Ray Tracing Rules
Parallel ray → through focal point
Central ray → unchanged direction
Focal ray → exits parallel (convex only)
Interactions
Drag the orange candle to move the object. Drag the focal point markers to change focal length.