Inspection accuracy ③.

The pixel resolution is 30μm (0.03mm),

Calculate the field of view range by applying the following formula.

 

PIXEL RESOLUTION = HORIZONTAL (X)/VERTICAL (Y) FIELD OF VIEW ÷ HORIZONTAL (X)/VERTICAL (Y) RESOLUTION

 

FIELD OF VIEW IN X DIRECTION

0.03 [mm/pixel] = X [mm] ÷ 640 [pixels].

X = 19.2 [mm].

 

FIELD OF VIEW IN Y DIRECTION

0.03 [mm/pixel] = Y [mm] ÷ 480 [pixels].

Y = 14.4 [mm].

 

The field of view is 19.2 × 14.4 [mm].

It is clear that a 300,000 pixel camera can only handle much smaller workpieces.

However, this does not mean that 30μm size defects can always be detected stably.

 

Minimum detection size = 4 [pixel square].

 

In general, the above formula is used.

Let's put it this way.

 

0.03 [mm/pixel] × 4 [pixel square] = 0.12 [mm square

 

If the workpiece is 19.2 × 14.4 mm or smaller,

We believe that a defect of 0.12 × 0.12 mm is stably detectable.