Design Nomenclature / Systems & Spec
First-angle projection
Also called European projection, ISO projection, first angle
This entry has not been translated yet and is shown in English.
The multiview arrangement in which the object sits between the viewer and the plane, so each view is projected through it and lands on the far side: the right-side view falls to the left of the front view, the top view below it. ISO practice — standard across Europe and most of Asia.
Not to be confused with
- Third-angle projectionThe arrangement in which the plane sits between the viewer and the object, so each view appears on the side it is seen from: the right-side view to the right of the front view, the top view above it. ASME practice — standard in the United States, Canada, and Japan.
- Orthographic projectionProjection along parallel lines perpendicular to the picture plane, so faces parallel to that plane record true size and shape with no perspective convergence. The basis of the multiview drawing — front, top, side, arranged by convention — supplemented by section, detail, and exploded views where one face can't say enough.
Origin
Named for the first quadrant of the two intersecting planes the object is imagined to occupy. The “European” tag only records where the convention stuck after the ISO and ANSI standards diverged.