CN1776472A - New optical fiber collimator packaging process - Google Patents

Abstract

Before assembly, phase of inclined end face of self-focusing lens is determined and in fixed position. Using CCD imaging system detects and adjusts phase of inclined end face of optical fiber connector pin to ensure parallel between two inclined end faces of the connector pin and self-focusing lens (GRIN) respectively basically. Then, being inside sleeve in stainless steel, the connector pin makes feed motion to adjust gap between the connector pin and the self-focusing lens inside sleeve. Under monitoring light signal from optical fiber to output of the self-focusing lens by optical instrument, the connector pin makes micro rotation in order to reach optimum position, maximal output optical power.

Description

A kind of new optical fiber collimator packaging process

Technical field:

The advanced person who the invention belongs to optical communication device makes the field, and it relates to a kind of optical fiber collimator encapsulation new technology.

Background technology:

Optical fiber collimator is the base components of light source components and parts.The effect of optical fiber collimator is that the diverging light with outgoing in the optical fiber becomes parallel beam or parallel beam converged to enter in the optical fiber and goes after collimating apparatus, to improve the coupling efficiency of optical fibre device.

Optical fiber collimator is (as laser instrument, detector, optoisolator, optical circulator, photoswitch, optical attenuator, light wavelength division multiplexing etc.) extensive application in optic communication device.Along with optical communication system to the developing rapidly of high capacity, two-forty direction, also more and more higher to the technical requirement that the industrialization manufacturing of optical fiber collimator proposes.And the packaging efficiency of optical fiber collimator and quality are one of " bottleneck " problems of its batch process manufacturing of restriction.

Optical fiber collimator (Collimator) is the basic optical device in optical fiber telecommunications system and the optical fiber sensing system, and it is made up of the GRIN Lens (GRIN) of 1/4th pitches and the contact pin and the stainless steel metal sleeve that have optical fiber.The material of GRIN Lens and optical fiber, contact pin is SiO ₂It is the inclined-plane (γ is generally 8 °) (as shown in Figure 1) of γ that GRIN Lens and contact pin respectively have with end plane angle.

The assembly technology of present existing optical fiber collimator is generally: the first step is contained in a end in the opaque small eccentric stainless steel metal sleeve regularly with GRIN Lens.Second step, the inclined-plane contact pin that will have optical fiber inserts the stainless steel metal sleeve other end, and do feeding and rotatablely move, the depth of parallelism and gap with optical fiber contact pins angled end-face and GRIN Lens angled end-face in the adjusting stainless steel metal sleeve, use optical instrument (as light power meter) to being incident in optical fiber and monitoring simultaneously by the light signal of GRIN Lens outgoing, when detected light-transfer characteristic is best (when reaching maximum), think that then the inclined-plane contact pin adjusted to the optimum position as the luminous power of output.Apply fixing glue to contact pin then, realize encapsulation.In the encapsulation process, the heating of collimation device element, so that viscose glue solidifies.

The gordian technique that collimating apparatus manufacturing at present is anxious to be solved is to realize obtaining minimum stable insertion loss with the shortest time and minimum cost.In the factor that influences collimating apparatus insertion loss, it is generally acknowledged to occupy an leading position in the depth of parallelism and the gap of optical fiber contact pins and GRIN Lens two angled end-faces, promptly its assembly technology directly influences the performance parameter of entire device.But the depth of parallelism of regulating optical fiber contact pins angled end-face and GRIN Lens angled end-face in opaque stainless steel metal sleeve has suitable difficulty.Therefore existing optical fiber collimator packaging process is further improved.

Summary of the invention:

Deficiency at prior art exists the object of the present invention is to provide a kind of new optical fiber collimator packaging process, to enhance productivity, guarantees the product workmanship.

The technical scheme of technical solution problem of the present invention is as follows: a kind of new optical fiber collimator packaging process, and its processing step is as follows:

A, GRIN Lens is installed on a end in the opaque stainless steel metal sleeve;

B, optical fiber contact pins lie in a horizontal plane in the other end outside of stainless steel metal sleeve, the CCD imaging system is vertical with surface level, the object lens of CCD imaging system be positioned at horizontal positioned optical fiber contact pins following or above, then the end face of optical fiber contact pins is exaggerated on the photosurface that images in CCD; Regulate imaging system, just can obtain the projected image of fiber end face by CCD, utilize the relation of this projected image and original image, obtain the phase information of optical fiber contact pins, and thus the anglec of rotation of optical fiber contact pins is regulated, make the angled end-face of optical fiber contact pins parallel with the angled end-face of GRIN Lens;

C, keep the contact pin horizontal direction to insert the stainless steel sleeve then, make optical fiber contact pins in the stainless steel sleeve, do feed motion, to regulate contact pin and the gap of GRIN Lens in the stainless steel metal sleeve, optical fiber contact pins is done little rotation simultaneously, with optical instrument to being incident in optical fiber and monitoring by the light signal of GRIN Lens outgoing, just can make the inclined-plane contact pin reach the optimum position apace, it is maximum that the luminous power of output reaches;

D, apply fixing glue to contact pin then, realize encapsulation.

The angled end-face of optical fiber contact pins and projection thereof are as shown in Figure 2.In assembling, optical fiber contact pins is placed surface level, and the CCD imaging system is vertical with surface level, and optical fiber contact pins is placed on following (or top) of the object lens (micro objective) of CCD imaging system, and then the end face of optical fiber contact pins is exaggerated on the photosurface that images in CCD.Regulate imaging system, just can obtain the projected image of clear fiber end face by CCD.Utilize the relation of this projected image and original image, obtain the phase information of optical fiber contact pins, and thus optical fiber contact pins is rotated adjusting, make the angled end-face of optical fiber contact pins parallel, for next work step is got ready with the angled end-face of GRIN Lens (GRIN).

By geometrical optics, the area of the projection plane of primary plane and reality has following relation:

Wherein, S is the area on plane, and α is the angle of projection plane and primary plane.Because the image that obtains of ccd video camera is exactly the image of optical fiber contact pins angled end-face projection plane, the image area of supposing to obtain the projection of optical fiber contact pins angled end-face is S _{Image projection}, the line enlargement ratio of imaging system is β, then Shi Ji projected area is:

If the fitter's bench plane is a surface level.When microscope and CCD camera are placed perpendicular to fitter's bench, projection plane be exactly table plane be surface level.So the angle α of optical fiber contact pins angled end-face and surface level can be obtained by following formula:

So have:

The method vector of supposing the optical fiber contact pins angled end-face is positioned at the XOZ plane, shown in first figure of Fig. 3.And the per unit system vector of establishing surface level is ${\stackrel{\→}{n}}_1=(1,\mathrm{0,0}).$

Because the processed inclined-plane that is polished to γ of ferrule end-face, when z axis rotated, the method vector was also around the rotation of Z axle at the optical fiber contact pins angled end-face, but the end points of method vector is all the time on a circle, shown in first figure of Fig. 3.When optical fiber when axis rotates the θ angle, the angle of fiber end face and surface level can be tried to achieve by the angle of method vector separately.

The motion diagram that second figure of Fig. 3 is method vector end points, the length of subjunctive vector OP is unit length l, then the length of O ' P is sin γ, when optical fiber during around Z axle rotation θ angle, the method vector is cos γ at the OO ' of Z axial projection, and the projection on X-axis, Y-axis is respectively-sin γ cos θ and sin γ sin θ, so its method vector is: ${\stackrel{\→}{n}}_2=(-\sin \mathrm{\γ}\cos \mathrm{\θ},\sin \mathrm{\γ}\sin \mathrm{\θ},\cos \mathrm{\γ}).$ So the angle α of surface level method vector and fiber end face method vector can be tried to achieve by following formula, that is:

$\cos \mathrm{\&alpha;}=\frac{|x_1\&CenterDot;x_2+{\mathrm{<figure-callout\; id="1"\; label="y"\; filenames="A20051011156700121.png,A20051011156700122.png"\; state="\{\{state\}\}">y</figure-callout>}}_1\&CenterDot;{\mathrm{<figure-callout\; id="2"\; label="y"\; filenames="A20051011156700121.png"\; state="\{\{state\}\}">y</figure-callout>}}_2+{\mathrm{<figure-callout\; id="1"\; label="z"\; filenames="A20051011156700121.png,A20051011156700122.png"\; state="\{\{state\}\}">z</figure-callout>}}_1\&CenterDot;{\mathrm{<figure-callout\; id="2"\; label="z"\; filenames="A20051011156700121.png"\; state="\{\{state\}\}">z</figure-callout>}}_2|}{\sqrt{x_1^2+{\mathrm{<figure-callout\; id="1"\; label="y"\; filenames="A20051011156700121.png,A20051011156700122.png"\; state="\{\{state\}\}">y</figure-callout>}}_1^2+{\mathrm{<figure-callout\; id="1"\; label="z"\; filenames="A20051011156700121.png,A20051011156700122.png"\; state="\{\{state\}\}">z</figure-callout>}}_1^2}\&CenterDot;\sqrt{x_2^2+{\mathrm{<figure-callout\; id="2"\; label="y"\; filenames="A20051011156700121.png"\; state="\{\{state\}\}">y</figure-callout>}}_2^2+{\mathrm{<figure-callout\; id="2"\; label="z"\; filenames="A20051011156700121.png"\; state="\{\{state\}\}">z</figure-callout>}}_2^2}}---\left(5\right)$

With surface level method vector With fiber end face method vector

Substitution formula (5):

cosα＝|-sinγcosθ|＝sinγcosθ (6)

Simultaneous formula (3) and formula (6) finally can obtain the angle θ (counterclockwise) that optical fiber contact pins need rotate:

Wherein the fiber end face image area is S _{Image projection}Algorithm be:

Utilize the projected area of the method calculating ferrule end-face of Digital Image Processing.To the digital picture that comprises ferrule end-face that collects with CCD, earlier remove noise with filtering algorithm, color (or gray scale) information according to the ferrule end-face image adopts serial boundary segmentation algorithm that image is handled then, be partitioned into target, and pass through scan image, calculate fiber end face target shared pixel in image, can accurately calculate the image area of fiber end face.If calculating the shared pixel of image end face by Flame Image Process is N ₁, and the area of display plane is S _{Display area}, exploration on display resolution ratio is N, then image end face projected area can be calculated with following formula:

Optical fiber collimator packaging process of the present invention, because GRIN Lens (GRIN) angled end-face phase place is determined before assembling and is in a fixed position, and direction vector is in the XOZ plane, make optical fiber contact pins again before not inserting the stainless steel metal sleeve, by detecting and adjust optical fiber contact pins angled end-face phase place, guaranteed two angled end-faces parallel of optical fiber contact pins and GRIN Lens (GRIN) substantially.Then, as long as keep contact pin to insert the stainless steel sleeve with correct attitude, and make optical fiber contact pins in the stainless steel sleeve, do feed motion, to regulate contact pin and the gap of GRIN Lens in the stainless steel metal sleeve, optical fiber contact pins is done little rotation simultaneously, with optical instrument (as light power meter) to being incident in optical fiber and monitoring by the light signal of GRIN Lens outgoing, just can make the inclined-plane contact pin reach the optimum position soon, guarantee the luminous power maximum of output, to enhance productivity, guarantee the product workmanship.

Description of drawings

Fig. 1 is the structural representation of optical fiber collimator structure;

Fig. 2 is the synoptic diagram of optical fiber contact pins angled end-face and projection;

Fig. 3 is the method schematic vector diagram at optical fiber rotation θ angle and the motion diagram of method vector end points;

Fig. 4 is an optical fiber contact pins angled end-face angle measurement apparatus structure synoptic diagram.

The number in the figure explanation

1-optical fiber contact pins 2-self-focusing camera lens

3-metal sleeve 4-CCD imaging system

5-anchor clamps 6-optical fiber

Embodiment

How further specify the present invention below in conjunction with accompanying drawing realizes:

Embodiment

In implementation process, the CCD model of the CCD imaging system of employing is

JVC colour TV camera T K-C921EC

1/3 " CCD, the horizontal resolution of 440,000 pixels, 535 tv lines

0.7Lux minimal illumination (F1.2,25%,, AGC open)

The high s/n ratio of 50dB (AGC OFF)

Built-in revolutionary 10bit Digital Image Processor (DSP)

The full functionality of CCTV purposes video camera is provided:

Can open/close electronic shutter

Can open/close automatic gain control (AGC)

Can be from motion tracking (ATW)/manual white balance mode of setting

Can open/close automatic backlight compensate function (BLC)

Can select two kinds of lens apertures of Video/DC to drive

The lens interface of compatible C and CS type

Small size, compact appearance design

Can accept two kinds of power supply supplies of 24V AC and 12V DC

Microscope is:

Model: Nikon E200 biological microscope

Amplification frequency scope: 40X-1500X (observation), 8X-500X (35mm microscope)

Eyepiece stalk: E2-TF hinge type three eyepiece inspection sections (30 ° at pitch angle, binocular interpupillary distance: 47mm-75mm)

Object lens: CFI E flat field achromatism 4X, NA=0.10

Converter: the formula of inclining four hole converters

Worktable: rectangle 216mmX54mm, stroke 78Xmm54Xmm adopts the coaxial handle of lower position X/Y

Illuminator: 6V 20W Halogen lamp LED

Thick fine setting is burnt: finely tune every circle 0.2mm, and the every circle of coarse adjustment 37.7mm, minimum scale 2 μ m (being positioned at the trimming hand wheel left side), coarse adjustment moment is adjustable, has from recovering focusing as platform, and the worktable handle is the same far away from the operator with focusing handwheel.

Light source is a metal halid lamp.

With collimating apparatus in the U.S. New Focus company circulator (C-I, C-II) is example:

The diameter D=1.8mm of the GRIN Lens of this model collimating apparatus, angled end-face drift angle γ is 8 °, calculates the area S original area=2.57mm of GRIN Lens angled end-face ², adopting the enlargement factor of imaging device is 160.As shown in Figure 4, GRIN Lens 2 is installed on a end in the opaque stainless steel metal sleeve 3; Outside the other end of stainless steel metal sleeve 3, optical fiber contact pins 1 is placed on surface level, CCD imaging system 4 is vertical with surface level, optical fiber contact pins 1 be placed on CCD imaging system 4 object lens below, then the end face of optical fiber contact pins 1 is exaggerated on the photosurface that images in CCD; Regulate imaging system, utilize the projected area of the method calculating ferrule end-face of Digital Image Processing.To the digital picture that comprises ferrule end-face that collects with CCD, earlier remove noise with filtering algorithm, color (or gray scale) information according to the ferrule end-face image adopts serial boundary segmentation algorithm that image is handled then, be partitioned into target, and pass through scan image, calculate fiber end face target shared pixel in image, can accurately calculate the image area of optical fiber 6 end faces, computing method are as follows:

If by digital image processing techniques, calculating the shared pixel of fiber end face image is N ₁=65288 pixels, and for 17 inches display, its effective area is 111.4558 square inches, i.e. S _{Display area}=719.0682 square centimeters, when exploration on display resolution ratio N is 1024*768, obtains image end face projected area and be:

Then pass through to calculate, can get by this method:

Be about to optical fiber contact pins 1 and press counterclockwise rotation 49.3 degree, keep contact pin 1 horizontal direction to insert the stainless steel sleeve then with anchor clamps 5, make optical fiber contact pins in the stainless steel sleeve, do feed motion, to regulate contact pin 1 and the gap of GRIN Lens 2 in stainless steel metal sleeve 3, optical fiber contact pins 1 is done little rotation simultaneously, with optical instrument to being incident in optical fiber and monitoring by the light signal of GRIN Lens 2 outgoing, the luminous power of output reaches maximum and promptly reaches the optimum position, applies fixing glue and heat to contact pin then to encapsulate.

Error analysis:

Optical fiber contact pins depends primarily on collection and its area Calculation Method of optical fiber contact pins angled end-face projected image with respect to the error of condenser lens angle (or phase place).The projected image area of fiber end face calculates accurate more, and the calculating of angle (or phase place) is also accurate more.Adopt Gaussian filter and mean filter that image is carried out pre-service, help to improve the computational accuracy of projected image area.Adopt serial boundary segmentation algorithm that optical fiber target is cut apart, how much ask its area according to the shared pixel of target again, this algorithm has very high precision.

By experimental verification repeatedly, the realization assembly method that the present invention proposes, the error of phase place can be controlled in margin tolerance ± 5 °, the accuracy requirement of optical fiber phase-detection in the time of can guaranteeing the optical fiber collimator assembling fully.

Claims (3)

1, plant new optical fiber collimator packaging process, its processing step is as follows:

A, GRIN Lens are installed on the end in the opaque stainless steel metal sleeve;

B, optical fiber contact pins lie in a horizontal plane in the other end outside of stainless steel metal sleeve, the CCD imaging system is vertical with surface level, the object lens of CCD imaging system be positioned at horizontal positioned optical fiber contact pins following or above, then the end face of optical fiber contact pins is exaggerated on the photosurface that images in CCD; Regulate imaging system, just can obtain the projected image of fiber end face by CCD, utilize the relation of this projected image and original image, obtain the phase information of optical fiber contact pins, and thus the anglec of rotation of optical fiber contact pins is regulated, make the angled end-face of optical fiber contact pins parallel with the angled end-face of GRIN Lens;

C, keep the contact pin horizontal direction to insert the stainless steel sleeve then, make optical fiber contact pins in the stainless steel sleeve, do feed motion, to regulate contact pin and the gap of GRIN Lens in the stainless steel metal sleeve, optical fiber contact pins is done little rotation simultaneously, with optical instrument to being incident in optical fiber and monitoring by the light signal of GRIN Lens outgoing, just can make the inclined-plane contact pin reach the optimum position apace, it is maximum that the luminous power of output reaches;

D, apply fixing glue to contact pin then, realize encapsulation.

2, a kind of new optical fiber collimator packaging process according to claim 1 is characterized in that: the optical fiber contact pins angled end-face is forwarded to by random phase derives as follows with the angle θ of the parallel required rotation of self-focusing camera lens angled end-face:

By geometrical optics, the area of the projection plane of primary plane and reality has following relation:

Wherein, S is the area on plane, and α is the angle of projection plane and primary plane;

S _{Image projection}Be the image area of optical fiber contact pins angled end-face projection, β is the line enlargement ratio of imaging system; So the angle α of optical fiber contact pins angled end-face and surface level can be obtained by following formula:

So have:

The method vector of supposing the optical fiber contact pins angled end-face is positioned at the XOZ plane, and the per unit system vector of establishing surface level is ${\stackrel{\&RightArrow;}{n}}_1=\left(\mathrm{1,0,0}\right),$ And ${\stackrel{\&RightArrow;}{n}}_2=(-\sin \mathrm{\&gamma;}\cos \mathrm{\&theta;},\sin \mathrm{\&gamma;}\sin \mathrm{\&theta;},\cos \mathrm{\&gamma;}),$ Wherein γ is the inclination angle of inclined plane of fine contact pin end face, and θ is that optical fiber is around the axis rotation angle;

The angle α of surface level method vector and fiber end face method vector can be tried to achieve by following formula, that is:

$\cos \mathrm{\&alpha;}=\frac{|x_1\&CenterDot;x_2+y_1\&CenterDot;y_2+z_1\&CenterDot;z_2|}{\sqrt{x_1^2+y_1^2+z_1^2}\&CenterDot;\sqrt{x_2^2+y_2^2+z_2^2}}---\left(5\right)$

With surface level method vector

With fiber end face method vector

Substitution formula (5):

cosα＝|-sinγcosθ|＝sinγcosθ (6)

Simultaneous formula (3) and formula (6) finally can obtain the angle θ (being rotated counterclockwise direction) that optical fiber contact pins need rotate:

3, a kind of new optical fiber collimator packaging process according to claim 2, it is characterized in that: the projected area of described ferrule end-face is S _{Image projection}Computing method be: to the digital picture that comprises ferrule end-face that collects with CCD, earlier remove noise with filtering algorithm, color or half-tone information according to the ferrule end-face image adopts serial boundary segmentation algorithm that image is handled then, be partitioned into target, and pass through scan image, calculate fiber end face target shared pixel in image, can calculate the projected area of fiber end face.

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