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7 Vision Systems S IPLACE 80S/F/G User’s Manual 7.3 Component Vision System Edition 07/97 from Software Version SR.010.xx 7 - 24 Line engine er Position Recognition Syste m for the IC Head for Flip Chips Camera type: SON…

SIPLACE 80S/F/G User’s Manual 7 Vision Systems

Edition 07/97 from Software Version SR.010.xx 7.3 Component Vision System

Line engineer 7 - 23

Component Position Recognition System of the Revolver Placement Head

The revolver placement head's optical system for component position recognition has already been described

in Section 7.3.1.

Component Position Recognition System for the IC Head with IC Sensor

All components of the optical system

–

CCD camera (SONY XC77 camera)

–

lens

–

optical band filter for suppression of unwanted reflections

are accommodated in a dustproof case. The useful field coverage of the CCD camera amounts to 38 mm x 38

mm. For position recognition or for testing leads the IC module is illuminated by three rows of LEDs using the

reflected light method and its image sharply reproduced using the lens on the CCD chip. Digital image pro-

cessing procedures are used to determine parameters for position, rotation angle and condition of leads of

fine-pitch components and BGAs (ball grid arrays).

Component Position Recognition System for the IC Head with FC Sensor

All of the optical components of the system, such as

–

CCD camera (SONY XC75C camera) and

–

lens,

are accommodated in a dustproof case. The visual field of the CCD camera is 12.2 mm x 9.2 mm. For position

recognition or the Ball test the flip chips are illuminated by two rows of LEDs using the reflected light method

and their image sharply reproduced using the lens on the CCD chip. Using digital image processing methods,

the parameters are determined for position, skew of the component and the number and position of the balls.

The vision evaluation unit is described in Section 7.2.1.

7.3.2.2 Technical Data

Position Recognition System for the IC Head for components with lead connections

Camera type: SONY XC77

Number of pixels: camera 768 (H) x 494 (V)

image 640 (H) x 484 (V)

Field of view: 38 mm x 38 mm

Lighting method: incident-light illumination (red light)

three levels of illumination

Image processing: HALE - grey-scale procedure (High Accuracy Lead

Extraction) with small components approx. 140 msec

Screen: RGB monitor (VGA mode) 640 x 484 pixels

Range of recognizable components: fine-pitch up to 55 mm x 55 mm and BGAs (Ball Grid Arrays)

Minimum lead spacing: 0.4 mm

Number of package forms:

≤

2047

7 Vision Systems SIPLACE 80S/F/G User’s Manual

7.3 Component Vision System Edition 07/97 from Software Version SR.010.xx

7 - 24 Line engineer

Position Recognition System for the IC Head for Flip Chips

Camera type: SONY XC75

Number of pixels: Camera 768 (H) x 494 (V)

Image 640 (H) x 484 (V)

Field of view: 12.2 mm x 9.2 mm

Lighting method: Incident-light illumination (red light)

Image processing: approx. 1 sec with standard flip chips

Screen: RGB monitor (VGA mode) 640 x 484 pixels

Range of components recognized: flip chips and fine pitch components up to approx. 15 mm x 15 mm

Minimum ball size: 80

Minimum pitch: 0.2 mm

Number of package forms:

≤

2047

7.3.2.3 Description of Functions

Components are optically centered at the revolver placement head, as described in Section 7.3.1.3 for the

80S machine. With the IC head two optical centering systems are available for the optical centering of compo-

nents:

–

the IC sensor for fine-pitch components up to a size of 55 mm x 55 mm and a minimum pitch of 0.4 mm

and for BGAs (ball grid arrays)

–

the FC sensor for flip chips and fine-pitch components up to a size of 15 mm x 15 mm and a minimum pitch

of 0.2 mm

The IC head picks up the components from the flatpack magazines and positions them over the correspond-

ing optical centering system. Staggered rows of LEDs evenly illuminate the component with red light. The dig-

ital image of the component created by the component camera is transmitted to the vision evaluation unit.

Here the image is evaluated in accordance with the component type. The results of evaluation provide infor-

mation on positional deviations, angle of rotation, lead conditions and the quality of the component image.

For BGAs and flip chips new illumination methods and special algorithms for obtaining component parameters

have been developed which enable this new generation of components to be optically centered as well.

Components which cannot be optically centered will be returned to the flatpack magazine by the IC head for

further analysis.

7.3.3 Criteria for the Registration of Components

●

Shape of the components

With the aid of optical component centering both regular and also irregular components can be centered.

The maximum number of leads permitted in the horizontal and in the vertical directions is 99 in each case.

Criteria for regular components

Definition

SIPLACE 80S/F/G User’s Manual 7 Vision Systems

Edition 07/97 from Software Version SR.010.xx 7.3 Component Vision System

Line engineer 7 - 25

A component is designated as regular when the following four conditions are satisfied:

–

rectangular package form (special case: square shape)

–

only one lead type per side

–

only one lead group per side

–

the lead groups located opposite are in each case symmetrical to the two main axes (x and y axes).

Fig. 7.3.1 Regular component

Criteria for irregular components

Definition

A component is designated as irregular when it does not satisfy the conditions for regular components.

Additional conditions for centering using the component vision system:

–

Up to 3 different lead types are permitted in one row.

–

Up to 15 groups are permitted in one row.