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SIPLACE 80S/F/G User’s Manual 7 Vision Systems Edition 07/97 from S oftware Version SR.010.xx 7. 3 Compo nent Vision System Line engi neer 7 - 23 Component Position Recognition S ystem of the Revolver Placement Head The …

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 - 22 Line engineer

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

Component sizes: 1 mm x 0.5 mm ... 18 mm x 14 mm

Range of recognizable components: TSOP, LCC, PLCC, QFP, SO series and so on

basically all components with J and gullwing leads

Minimum lead spacing: 0.5 mm

Number of package forms:

≤

2047

7.3.1.3 Description of Function

One segment of the placement head picks up a component at star station 1. As the revolving star advances,

further components are picked up. Star station 8 accommodates the optical unit of the component vision sys-

tem. On its arrival the component is evenly illuminated with red light by staggered rows of LED's. The lens cre-

ates sharp imaging of components up to a height of 5 mm on the CCD chip of the camera.

The digital imaging of the component created by the component camera is transmitted to the vision evaluation

unit. Using digital image processing (HALE procedure) the evaluation unit compares the component image

with an artificial model previously created with the GF editor (GF= package form). The parameters obtained

from this provide information on positional deviations, rotational angle, lead condition, and component reiden-

tification. The HALE procedure has proved to be highly resistant to interference factors such as interference

reflections, the differing reflection characteristics of lead, incidental light influences, and so on. Once mea-

surement has been successfully completed the segment rotates the component in star station 9 in the correct

placement direction. In star station 1 the component is then placed correctly oriented onto the circuit board.

7.3.2 Component Vision System in the SIPLACE 80 F Placement

Systems

7.3.2.1 System Description

The component vision system consists of

●

the optical system for recognizing the position of components.

The revolver head is equipped with a component position recognition system in star station 8

(see Fig. 7.1.2).

Up to two component vision systems can be used for the IC placement head. These are mounted perma-

nently on the machine base (see Fig. 7.1.5). One (vision system) is used for the optical centering of con-

ventional components with leads. The other - with a FC sensor - optically centers flip chips (see Section

7.6.3.4 Option “Measure component”).

●

the vision evaluation unit

The vision evaluation unit for both PCB and component position recognition is accommodated in the con-

trol unit (see Fig. 7.1.6).

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