Technical Drawings in Interiors

TECHNICAL DRAWINGS IN INTERIORS 4(1+3)

Lesson 6:Oblique Projection Drawings

Definition and method

"Oblique projection" is a type of parallel projection. Thus, it projects an image by intersecting parallel rays ("projectors") from the three-dimensional source object with the drawing surface ("projection plane"). In both "oblique projection" and orthographic projection (the other type of "parallel projection"), parallel lines of the source object produce parallel lines in the projected image. The "projectors" in "oblique projection" intersect the "projection plane" at an angle to produce the projected image, as opposed to the perpendicular angle used in orthographic projection.
In oblique projection

• Projectors from an object are parallel to each other and inclined to the plane of projection
• The object is placed in such a way that one of its prominent faces remains parallel to the plane of projection.
• The object is drawn with the actual dimensions
• The faces of the object which are perpendicular to the plane of projection will be distorted in shape and size
• The choice of position of the object depends upon the shape and size