Orthographic projection

In this slide i define the projection.

1. Orthographic projection By- Bhupendra Kumar Singh Lecturer- Mech. Engg. Govt. Poly. Etah (U.P.)

2. Projection is the representation of an object on the picture plane viewed by an observer from some distance. It is most valuable means of communication in engineering drawing. Aim of projection mean is to describe the shape of any object in refrence plane. PROJECTION

3. Orthographic projection (or orthogonal projection) is a means of representing a three dimensional object in two dimensions. It is a form of parallel projection, where all the projection lines are orthogonal to the projection plane. ORTHOGRAPHIC PROJECTION

4. QUADRANTS In 1 st and 2 nd quadrants the object is above the H.P. In 3 rd and 4 th quadrants the object is below the H.P.

5. Here projection are obtained keeping an objects in 1 st quadrants. Here objects remains in between observer and projection. As the picture plane remains behind the objects. FIRST ANGLE ORTHOGRAPHIC PROJECTION

6. Another example of first angle orthographic projection is shown below

7. In this method the object is kept in 3 rd quadrant. All reference plane is treated as transparent. Here projections are in between objects and observer. THIRD ANGLE ORTHOGRAPHIC PROJECTION

8. Example of third angle orthographic projection is shown in below

9. Another example of first angle orthographic projection is shown below

10. THANK YOU