TWI696824B - Positioning device and method before contact lens inpection - Google Patents

Abstract

A positioning device before contact lens inspection includes at least one flat bottom glass and at least one lens positioning mechanism. The flat lens bottom glass defines a inspection pocket having a circular wall, and the flat bottom glass is adapted for holding a contact lens to be inspected. The lens positioning mechanism includes a water injection needle, a water injection control valve and a water pipe. The water injection needle and the water pipe are connected with the water injection control valve, and the water injection control valve is adapted for quantitively injecting water in the water pipe through the water injection needle toward the inspection pocket. The water injection needle has a distal end extending in an extending direction. The point of the circular wall closest to the distal end has a reference tangential direction. When viewed from the angle of the flat bottom glass, there is an angle of less than 30 degrees between the extending direction and the reference tangential direction.

Description

Positioning equipment and method before contact lens inspection

The invention relates to a detection device and a detection method, in particular to a positioning device and a method for contact lens defect detection.

Contact lens is a common vision correction lens, which can be divided into hard and soft contact lenses according to the material. In recent years, color contact lenses have also been widely loved by consumers. It is to sandwich the color material between two pieces of silicon hydrogel to make the pupils appear larger, brighter and more refreshing, or to change the color of the pupils. .

This sandwich sandwich lens is prone to produce interlayer bubbles during the multi-layer bonding process, resulting in burrs, cracks, wrinkles or bubbles in the formed lens. Therefore, after forming the contact lens, it must be checked whether the lens has the above defects .

However, in the prior art, due to the poor matching between the detected jig and the lens, when the lens is placed in the detection cavity, the lens is often unable to be accurately positioned in the center of the detection cavity, and it is easy to rush the lens toward the wall surface when water is injected. The lens is easy to lean against the wall surface, which makes it impossible for machine vision to recognize the lens with a round outline in the detection cavity, and then jump out of the phenomenon of detection failure or misinterpretation as a defective product, which must be further detected manually. In existing detection equipment, the misjudgment rate due to the aforementioned problems is as high as 30% to 40%.

In view of this, the main objective of the present invention is to provide a contact lens positioning device and method that can significantly reduce the detection misjudgment rate through accurate positioning of lenses.

In order to achieve the above and other objects, the present invention provides a positioning device before contact lens inspection, which includes at least one inspection container and at least one lens positioning mechanism. The detection container defines a detection cavity, which has a circular wall surface, the detection container is made of a light-transmissive material, and the detection container is used to hold a contact lens to be tested. The lens positioning mechanism includes a water injection head, a water injection control valve and a water pipe. The water injection head and the water pipe are connected to the water injection control valve. The water injection control valve is used to quantitatively inject the water in the water pipe toward the detection cavity through the water injection head. It extends in an extension direction, and the water injection head has a free end, and the point of the circular wall closest to the free end has a reference tangent direction. Among them, when viewed from the angle of looking down at the detection container, there is only an included angle between the extending direction and the reference tangent direction that is less than 30∘.

In order to achieve the above and other objects, the present invention also provides a positioning method before contact lens inspection, which uses the aforementioned positioning device and includes:

Placing a contact lens to be tested into the testing cavity; and

The water injection control valve is activated, and water is quantitatively injected into the detection cavity through the water injection head, so that water circulates in the detection cavity along the circular wall surface.

In this way, when water swirls in the detection cavity, the contact lens lens that originally leaned on the round wall surface can be rushed toward the center of the detection cavity, because the center of the detection cavity is when the water swirls and flows. The lowest position, so the lens will fall toward the lowest center of the water surface when it is subjected to gravity, thus achieving the purpose of accurately positioning the lens at the center of the detection cavity, and thereby greatly reducing the misjudgment rate of subsequent machine vision recognition.

Please refer to FIGS. 1 to 3, which depicts a first embodiment of a positioning device before contact lens inspection, which includes a plurality of detection containers 10, a plurality of lens positioning mechanisms 20, a detection container fixing frame 30, and a Positioning mechanism fixing frame 40. In this embodiment, the number of detection containers 10 and lens positioning mechanisms 20 are equal; in other possible implementation manners, one lens positioning mechanism can also be used in combination with multiple detection containers 10. The detection container fixing frame 30 and the positioning mechanism fixing frame 40 are respectively used to fix the detection containers 10 and the lens positioning mechanism 20.

The detection container 10 defines a detection cavity 11 having a circular wall surface 12 for holding a contact lens 1 to be tested. The detection container 10 is made of a light-transmissive material, such as glass or plastic. More specifically, the detection container 10 may be a glass or plastic cup, for example. In a possible embodiment, the detection container 10 may have a flat bottom surface or a concave bottom surface. The greater the number of detection containers included in the positioning device, the higher the efficiency of positioning, but the larger the space occupied by the device. Therefore, the number of detection containers can be adjusted to more than one depending on the actual use requirements.

The lens positioning mechanism 20 includes a water injection head 21, a water injection control valve 22 and a water pipe 23. Both the water injection head 21 and the water pipe 23 communicate with the water injection control valve 22. The water injection control valve 22 is used to quantitatively inject the water in the water pipe 23 toward the detection cavity 11 via the water injection head 21. The water injection head 21 has a free end 211, and the water injection head 21 extends into the detection cavity 11 in an extension direction D1, and the point P of the circular wall surface 12 closest to the free end 211 has a reference tangent direction D2.

Among them, as shown in FIG. 3, when viewed from the perspective of the detection container 10 in a plan view, there is an angle θ between the extension direction D1 and the reference tangent direction D2 that is less than 30∘, in addition, the free end 211 and the circular wall surface 12 are most The distance between the point P close to the free end 211 is L1, and the distance between the free end 211 and the center of the detection container 10 is L2. The two satisfy the following relationship: 0 <L1/L2 <0.5. In a possible embodiment, the included angle θ is less than 25∘. In a possible embodiment, the included angle is less than 20∘. In a possible embodiment, the following relationship is satisfied: 0 <L1/L2 <0.4. In a possible embodiment, the following relationship is satisfied: 0 <L1/L2 <0.3. In this embodiment, the included angle is approximately 19∘, and L1/L2 is 0.26. That is, the extension direction D1 of the water injection head 21 is as close as possible to the reference tangential direction D2 of the detection container 20, so that during subsequent water injection, it is easy to form a vortex in the detection cavity.

The first embodiment of the method for positioning a contact lens before detection according to the present invention will be described below with reference to FIGS. 4 to 7, and the positioning device as described above is applied. The positioning method includes:

As shown in Figs. 4 and 5, the contact lens 1 is placed into each detection cavity 11 one by one using a robotic arm or manually; when placed, the lens 1 may not be located in the center of the detection cavity 11 due to operational errors;

Next, as shown in FIGS. 6 and 7, the water injection control valve 22 is activated, and water is quantitatively injected into the detection cavity 11 through the water injection head 21, so that the water swirls and flows in the detection cavity 11 along the circular wall surface 12. Water can flush the lens 1 away from the circular wall surface 12, and automatically flows to the position where the detection cavity 11 approaches the center with the vortex.

Through the above technology, the positioning device and the positioning method of the present invention can greatly reduce the problem of the lens leaning against the circular wall surface, and avoid the situation of misjudgment of machine vision due to the misalignment of the lens. In actual testing, when the lens defect detection is performed after positioning by the positioning device and positioning method of the present invention, the misjudgment rate can be reduced to less than 5%, and most of the misjudgment is not caused by the lens leaning against the circular wall surface; Since the misjudgment rate of the existing equipment reaches 30% to 40%, the technical means provided by the present invention greatly reduce the situation of misjudgment, which is an improved technology with a very significant technical effect.

1: lens 10: Detection container 11: Detect the cavity 12: Round wall 20: Lens positioning mechanism 21: Water injection head 211: Free end 22: Water injection control valve 23: water pipe 30: Inspection container fixing frame 40: Positioning mechanism fixing frame D1: Extension direction D2: Reference tangent direction L1, L2: distance P: point θ: angle

Figure 1 is a perspective view of a first embodiment of a positioning device of the present invention.

Fig. 2 is a top view of the first embodiment of the positioning device of the present invention.

Fig. 3 is an enlarged schematic plan view of the first embodiment of the positioning device of the present invention.

4 to 7 are a schematic plan view and a schematic cross-sectional view of the use state of the first embodiment of the positioning device of the present invention.

10: Detection container

11: Detect the cavity

12: Round wall

21: Water injection head

211: Free end

30: Inspection container fixing frame

D1: Extension direction

D2: Reference tangent direction

L1, L2: distance

P: point

θ: angle

Claims (4)

A positioning device before contact lens inspection includes: at least one detection container, defining a detection cavity, the detection container has a circular wall surface, and the detection container is made of a light-transmissive material, the detection container is used to Containing a contact lens to be tested; and at least one lens positioning mechanism, including a water injection head, a water injection control valve and a water pipe, the water injection head and the water pipe are in communication with the water injection control valve, the water injection control valve is used To quantitatively inject the water in the water pipe toward the detection cavity through the water injection head, the water injection head extends in an extending direction, and the water injection head has a free end, and the point of the circular wall closest to the free end has a Reference tangent direction; wherein, when viewed from an angle that looks down on the detection container, the extension direction and the reference tangent direction have an angle of less than 30°; wherein, when viewed from an angle that looks down on the detection container, the free The distance between the end and the point of the circular wall closest to the free end is L1, and the distance between the free end and the center of the circle of the detection container is L2, and the following relationship is satisfied: 0<L1/L2<0.5. The positioning device according to claim 1, further comprising a detection container fixing frame, the at least one detection container is fixed to the detection container fixing frame. The positioning device according to claim 1, further comprising a positioning mechanism fixing frame, and the at least one lens positioning mechanism is fixed to the positioning mechanism fixing frame. A positioning method before contact lens detection, which uses the positioning device as described in any one of claims 1 to 3, the positioning method comprising: placing a contact lens to be detected into the detection cavity; as well as The water injection control valve is activated, and water is quantitatively injected into the detection cavity through the water injection head, so that water circulates in the detection cavity along the circular wall surface.

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