CPC Subgroup
G03B 21/132 Overhead projectors, i.e. capable of projecting hand-writing or drawing during action (epidiascopic projectors G03B21/08)
Full Title
Projectors or projection-type viewers; Accessories therefor (devices for changing pictures G03B23/00) > Overhead projectors, i.e. capable of projecting hand-writing or drawing during action (epidiascopic projectors G03B21/08)