Device and method for aligning and bonding lens array and PD array with high precision

Patent metadata

Field	Value
Publication number	US-9964717-B2
Application number	US-201415534863-A
Country	US
Kind code	B2
Filing date	Dec 17, 2014
Priority date	Dec 11, 2014
Publication date	May 8, 2018
Grant date	May 8, 2018

Abstract

Device and method are provided to align and bond a lens array to a PD array with high precision, which can implement aligning and bonding of the lens array automatically. A telescopic rod of the stepping actuator is adjusted until photosensitive areas of the PD array form a clear image on the image acquisition CCD through the lens array, an adjusted distance h1 of the telescopic rod is recorded, and a position coordinate (xn, yn) of center of each circular photosensitive area in the image may be obtained, and a slope k1 of a line connecting the centers of the photosensitive areas is calculated. The telescopic rod is adjusted again, and a slope k2 of a line connecting the centers of the apertures of the lens array is calculated. Based on calculated values Δxn, Δyn, arctan(k1)−arctan(k2), the high-resolution adjustment stage is adjusted to adjust position of the lens array.

First claim

The invention claimed is:

1. An aligning bonding device for aligning a lens array to a PD array with high precision, comprising: a cassette holding fixture ( 103 ), a lens array holding fixture ( 104 ), a gantry ( 105 ), a securing frame ( 106 ), an image acquisition CCD ( 107 ), a high-resolution adjustment stage ( 109 ), a first bubble level ( 110 - 1 ), a second bubble level ( 110 - 2 ), a third bubble level ( 110 - 3 ), a slide ( 111 ), a slide platform ( 112 ), a one-axis linear stage ( 113 ), a connecting plate ( 114 ), a transition block ( 115 ), and a stepping actuator ( 116 ), wherein the high-resolution adjustment stage ( 109 ) is fixed on a pedestal of the gantry ( 105 ), the transition block ( 115 ) is fixed on the high-resolution adjustment stage ( 109 ), the first bubble level ( 110 - 1 ) is provided on the transition block ( 115 ), the securing frame ( 106 ) is fixed on the gantry ( 105 ), the slide ( 111 ) is provided within the securing frame ( 106 ), the slide ( 111 ) is embedded in the slide platform ( 112 ), the one-axis linear stage ( 113 ) is provided on the slide platform ( 112 ), a rear surface of the image acquisition CCD ( 107 ) is fixed on the connecting plate ( 114 ), the connecting plate ( 114 ) is fixed on the one-axis linear stage ( 113 ), a rear surface of the connecting plate ( 114 ) is provided with the second bubble level ( 110 - 2 ), the stepping actuator ( 116 ) is positioned below the securing frame ( 106 ) supporting the slide platform ( 112 ), the stepping actuator ( 116 ) functions to move the slide platform ( 112 ) up and down along the slide ( 111 ), the cassette holding fixture ( 103 ) is positioned under the image acquisition CCD ( 107 ), and the third bubble level ( 110 - 3 ) is provided on the cassette holding fixture ( 103 ).

2. The aligning bonding device for aligning a lens array to a PD array with high precision of claim 1 , further comprising a pressure sensor ( 101 ), one end of which is provided on the transition block ( 115 ), and the other end is connected to the lens array holding fixture ( 104 ).

3. The aligning bonding device for aligning a lens array to a PD array with high precision of claim 1 , further comprising a standard CCD ( 108 ) provided at a side of the cassette holding fixture ( 104 ) to observe interior of the cassette ( 117 ).

4. The aligning bonding device for aligning a lens array to a PD array with high precision of claim 3 , wherein the lens array holding fixture ( 104 ) includes two arms, and end holding portions of the two arms are provided with grooves.

5. The aligning bonding device for aligning a lens array to a PD array with high precision of claim 2 , further comprising a controller ( 102 ) in connection with the pressure sensor ( 101 ) to read pressure voltage signal fed back from the pressure sensor ( 101 ).

6. A method for aligning a lens array to a PD array with high precision by using the aligning bonding device for aligning a lens array to a PD array with high precision of claim 1 , comprising the following steps:
holding the lens array ( 121 ) with the lens array holding fixture ( 104 );
fixing the cassette ( 117 ) to be aligned, in which the PD array ( 118 ) to be aligned and a pair of glass blocks ( 119 ) are arranged, on the cassette holding fixture ( 103 ), adjusting the image acquisition CCD ( 107 ) and the cassette ( 117 ) in which the PD array is placed to a completely parallel status so that the image acquisition CCD ( 107 ) has a shooting sight completely perpendicular to the cassette ( 117 );
adjusting the high-resolution adjustment stage ( 109 ) to make the lens array ( 121 ) just be in contact with the pair of glass blocks ( 119 ) and determine a height dimension of the lens array ( 121 );
adjusting a telescopic rod of the stepping actuator connected to the image acquisition CCD ( 107 ) to move the image acquisition CCD ( 107 ) up and down until photosensitive areas of the PD array form a clear image on the image acquisition CCD ( 107 ) through the lens array ( 121 ), recording an adjusted distance h1 of the telescopic rod of the stepping actuator, acquiring an image and determining a position coordinate of center of each circular photosensitive area of the PD array ( 118 ) in the image, a coordinate of the n-th point being recorded as (xn, yn), and calculating a slope k1 of a line connecting the centers of the photosensitive areas;
adjusting the telescopic rod of the stepping actuator again until the lens array ( 121 ) forms a clear image in the field of view of the image acquisition CCD ( 107 ), recording an adjusted distance h2 of the telescopic rod of the actuator, acquiring an image and determining position coordinates of centers of apertures of the lens array ( 121 ) corresponding to the PD array, a coordinate of the n-th point being recorded as (x′n, y′n), and calculating a slope k2 of a line connecting the centers of the apertures of the lens array ( 121 );
calculating difference between the coordinates of the centers of the photosensitive areas and the coordinates of the centers of the corresponding apertures of the lens array, wherein a coordinate difference of the n-th point is recorded as Δxn=xn−x′n, Δyn=yn−y′n;
adjusting the high-resolution adjustment stage ( 109 ) to adjust position of the lens array ( 121 ) based on the calculated values Δxn, Δyn, arctan(k1)−arctan(k2), repeating the above two image acquiring steps, the calculating step and the adjusting step until the following condition is satisfied: for any point n, Δxn=Δyn=0, and k1=k2, thereby achieving coincidence of the centers of the apertures of the lens array with the centers of the photosensitive areas of the PD array.

7. The method for aligning a lens array to a PD array with high precision of claim 6 , wherein a method for making the shooting sight of the image acquisition CCD ( 107 ) completely perpendicular to the cassette ( 117 ) comprises: adjusting the high-resolution adjustment stage ( 109 ) to make the transition block ( 115 ), the cassette holding fixture ( 103 ) and the connecting plate ( 114 ) be in a horizontal status as determined through the first bubble level ( 110 - 1 ), the second bubble level ( 110 - 2 ) and the third bubble level ( 110 - 3 ), respectively.

8. The method for aligning a lens array to a PD array with high precision of claim 6 , wherein a method for adjusting the high-resolution adjustment stage ( 109 ) to make the lens array ( 121 ) and the pair of glass blocks ( 119 ) just be in contact with each other comprises: moving the lens array ( 121 ) to be over the PD array ( 118 ) while observing through the standard CCD ( 108 ), adjusting the high-resolution adjustment stage ( 109 ) to gradually move the lens array ( 121 ) downwards while observing a pressure value indicated on the pressure sensor ( 101 ) installed on the lens array holding fixture ( 104 ), and stopping moving the lens array ( 121 ) downwards when the pressure value changes.

9. The method for aligning a lens array to a PD array with high precision of claim 6 , wherein the high-resolution adjustment stage is adjusted in a manual mode or in an automatic control mode until the centers of the apertures of the lens array ( 121 ) are coincided with the centers of the photosensitive areas of the PD array ( 118 ).

Assignees

• Accelink Tech Co Ltd

Inventors

• Shi Chuan
• Xi Huali
• Jiang Xiong
• Liang Xuerui
• Yin Hualin
• Ma Weidong

Classifications

• G02B6/4239

  Adhesive bonding; Encapsulation with polymer material · CPC title

• G02B6/4221 Primary

  involving a visual detection of the position of the elements, e.g. by using a microscope or a camera · CPC title

• G02B6/4227

  Active alignment methods, e.g. procedures and algorithms · CPC title

• G02B6/4206

  Optical features (G02B6/4207, G02B6/421 take precedence) · CPC title

• G02B6/4219 Primary

  Mechanical fixtures for holding or positioning the elements relative to each other in the couplings; Alignment methods for the elements, e.g. measuring or observing methods especially used therefor · CPC title