KR20100000413U - Rectangular optical glass lens - Google Patents

Abstract

The present invention relates to a rectangular optical glass lens, wherein a rectangular glass blank is placed between an upper mold and a lower mold of a multi-cavity mold, and then heated so that the rectangular glass blank is molded into a lens sheet having a plurality of lenses. And pressurized.

The rectangular glass blank is molded into a lens sheet having a plurality of optical surfaces and the lens sheet is cut to form a plurality of rectangular optical glass lenses. The rectangular optical glass lens manufactured by the above-described method includes two optical surfaces serving as rectangular annular surfaces in an optical region and a non-optical region surrounding the optical surface.

The annular surface is a rectangular portion having four right angles at each corner, and the right angle and the rectangular shape are cut and formed by the lens sheet. Therefore, the manufacturing method of the rectangular optical glass lens is simple and the manufactured lens can be easily assembled with the lens module.

Optical Glass Lens, Rectangle, Mold, Lens Sheet, Camera

Description

Rectangular optical glass lens {RECTANGULAR OPTICAL GLASS LENS}

The present invention relates to a rectangular optical glass lens, and more particularly, to a rectangular optical glass lens having an optical surface, a right-angular circumference, and applicable to a camera phone at a low production cost. Use an easy-to-use sensor such as a coupled device or a complementary metal-oxide semiconductor (CMOS).

Many electronic devices such as digital cameras, PC cameras, network cameras, mobile phones or personal digital assistants (PDAs) are required to be manufactured with image capture devices. In order to be convenient for the user and portable, the image capturing apparatus generates high quality images, has a compact size, and is inexpensive.

Glass precision molding technology is used to produce aspherical mold glass lenses that meet high resolution, high quality reproduction and low cost, such as those proposed in patents US2006 / 0107695, US2007 / 0043463, TW095101830, TW095133807, JP63-295448, etc. Apply.

The glass preform is moved to the mold forming step to undergo a heating and casting step. At this time, the increasing pressure in the upper mold and the lower mold of the mold forming step to deliver the flexible glass forms the same shape as the surface of the upper mold and the lower mold.

Molded glass lenses are produced after the cooling step. US 7,312,933, which describes a rectangular monoblock optical lens 1a for reducing the manufacturing cost, is manufactured from a rectangular glass unit molded as shown in FIG.

Looking at JP63-304201 and US Patent Publication 2005/041215, lens arrays manufactured by press-molding are disclosed. Looking at JP 02-044033, the flat glass 2a of Fig. 2 is heated and pressed in the mold to be formed into a lens. In Fig. 2, each lens 1b is obtained by cutting the flat glass 2a.

Looking at US 2004/165095, a lens having an infrared filter produced by a multi-cavity glass molding method is disclosed. The insulator multilayer film is provided as one of the surfaces of the planar convex lens of glass and cut with a number of infrared filters. Multi-cavity glass molding methods can be applied to glass molding technology, but such methods are only feasible in the manufacture of aspherical, planar-convex and planar-convex lenses. When applying an aspherical lens in a mini camera or camera phone, residual air remains in the mold cavity during the heating and pressing processes. This reduces the accuracy of the aspherical lens.

Several methods for solving the problem with the residual air are presented. For example, referring to JP2002-003225, JP05-286730, JP06-191861, US 20050172671, and EP0648712, the problem of residual air can be solved by pressure control, temperature control or surface roughness. Looking at JP1-291424, TWI248919, JP2000-044260, TW200640807, US2005 / 0242454, air channels are provided in the mold to release residual air.

Many molten glass, however, is flooded with air exhaust channels to form brims. In addition, the process needs to form a brim. Or as shown in JP61-291424, JP08-337428, and US 7,159,420, grooves or ventilative holes are provided in the molding unit, in particular in the lower molding unit. However, the above-described design causes projections to occur in the molded lens and causes problems in subsequent manufacturing or assembly processes.

In general, the air discharge effect is exhibited by the air discharge efficiency δ which is the same as the cross-sectional area of the air discharge channel divided by the volume of the mold cavity (δ = cross-sectional area of the air discharge channel / volume of the mold cavity). In the molding process, the open emission efficiency δ is larger and the air accumulation is smaller. In contrast, when the air emission efficiency δ becomes small, it is difficult to discharge the air. It is preferable that δ is larger than 0.25 in order to discharge air efficiently. According to the multi-cavity mold, especially the cavity is close to the center of the mold core, which makes it difficult to evacuate the air. After a long time experiment, the results show that the rectangular glass should have a mold cavity value greater than 0.25 near the end of the mold. The δ value of the mold cavity should be proportional to the distance from the mold cavity to the mold and increases exponentially. Therefore, while producing multi-cavity optical glass lenses by precise molding glass technology, the molds must be designed with high δ values without creating protrusions on the lens to meet the requirements of mass production and high yield rate. .

An object of the present invention is to place a rectangular optical glass lens and a rectangular glass blank between an upper mold and a lower mold of a multi-cavity mold, and then heat the rectangular glass blank to be molded into a lens sheet having a plurality of lenses. It is to provide a manufacturing method that is pressurized.

The lens sheet is cut to form a plurality of lenses. The rectangular lens produced by the method described above comprises two aspherical optical surfaces and a rectangular circumference of the non-optical region around the optical surface. The annular surface is a rectangular portion having four right angles in each configuration, while the square and the quadrangle are formed by the cutting of the glass blank. Therefore, the manufacturing process of the rectangular optical glass is simple and the manufactured lens is combined with the conventional lens module.

Another object of the present invention is to provide a rectangular optical glass lens and a method of manufacturing the same. The surfaces of the upper and lower molds of the multiple cavity mold are provided with a plurality of protrusions. During the manufacturing process, air in the mold cavity is released from the gaps around the formed protrusions due to the height difference between the protrusions and the rectangular glass blanks. Therefore, the air discharge efficiency δ of the mold cavity around the mold is not less than 0.25 (δ≥0.25), and the air emission efficiency near the center of the mold cavity of the mold is not less than 0.5 (δ≥0.5). The air in the cavity is effectively released during the molding process to avoid residual air in the mold cavity resulting in aspherical ill-precision. Corresponding grooves are also formed in the rectangular annular surface of the lens sheet.

It is also an object of the present invention to provide a rectangular optical glass lens and a method of manufacturing the lens. A plurality of reverse V-shaped strip protrusions are provided on the cavity surface of the multiple cavity mold at predetermined intervals in the longitudinal and / or transverse directions. The reverse V-shaped strip protrusion forms a corresponding V-shaped cutting groove on the lens sheet. The cutting groove is used as a cutting line portion of the lens sheet and the lens sheet is cut into a plurality of rectangular lenses of the same size.

In order to achieve the above object, the present invention is formed by cutting a lens sheet having a plurality of lens structures manufactured by a rectangular glass blank which is heated and pressed between the upper mold and the lower mold of the multiple cavity mold. A rectangular optical glass lens comprising: an aspherical first optical surface provided on one side of a lens; An aspherical second optical surface provided on the opposite side of the first optical surface; And a rectangular annular surface provided around the first optical surface and the second optical surface, wherein the first optical surface and the second optical surface are optical regions of a rectangular optical glass lens, and the rectangular annular surface is a non-optical region. And a quadrangular shape having four corners, wherein the rectangular annular surface is formed by cutting the lens sheet.

As described above, the rectangular optical glass lens according to the present invention is a rectangular glass blank is placed between the upper mold and the lower mold of the multi-cavity mold, the rectangular glass blank is a lens sheet having a plurality of lenses Heated and pressurized to be molded, the lens sheet is cut to form a plurality of rectangular optical glass lens, in particular, the rectangular portion of each corner having a right angle is a simple manufacturing method and the lens manufactured by the manufacturing method is a lens module and It can be easily assembled.

Hereinafter, in order to be described in detail so that those skilled in the art can easily implement the present invention, the most preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. . Other objects, features, and operational advantages, including the object, operation, and effect of the present invention, will become more apparent from the description of the preferred embodiment.

First Embodiment

3 and 4, the rectangular optical glass lens 1 according to the present invention is composed of a first optical surface 12, a second optical surface 13 and an annular surface 11. The first optical surface 12 and the second optical surface 13 are convex and concave surfaces, respectively. Both surfaces are aspherical. The annular surface 11 is a rectangular member having four right angles at each corner, and may be referred to as a rectangular annular surface. The focal length of the lens 1 is 1.87 mm in the embodiment. When assembled in the lens module 3 as shown in Figs. 5 and 6, the rectangular annular surface 11 is fixed on the lens holder 31, the light is aperture 32 and CMOS sensor It passes through the first and second optical surfaces 12, 13 through the focus on (not shown). The diagonal of the CMOS sensor is less than 1/7 "inch. In an embodiment of the present invention, the relational parameters for the first optical surface and the second optical surface are designed by the aspherical surface equation (1) and are shown in Table 1.

Aspheric Equation (1)

C = 1 / R in the above equation

X (sag value) is the distance from the tangent plane at the vertex of the aspherical surface relative to the aspherical position.

Y is the distance from the optical axis to the Y axis.

C is a curve in the X axis; Inverse of the radius of the curve at the vertex

K: conic constant

A ₂ -A _n : each aspherical coefficient, 2nd to nth power of Y

As shown in Fig. 9, the manufacturing method of the rectangular optical glass lens 1 includes the following steps.

Providing a rectangular glass blank 4 formed of H-BAL42 glass material having a predetermined thickness to reduce heating and pressurization during the molding process;

Providing a multiple cavity mold (5) having an upper mold, a lower mold (51, 52) and a cavity surface (50) provided with a plurality of convex aspherical surfaces and corresponding concave / convex aspherical surfaces;

Heating the glass transition temperature by the heater (53), and setting the glass blank (4) between the upper mold and the lower mold (51, 52); In this step, the upper and lower molds 51, 52 for molding such that the rectangular glass blank 4 is molded into a rent sheet 2 having a plurality of first optical surfaces 12 and corresponding second optical surfaces 13. Heating and pressurization)

Cutting the lens sheet 2 with respective rectangular optical glass lenses 1 comprising a rectangular circumference, a first optical surface 12 (convex aspherical surface) and a second optical surface 13 (concave aspherical surface). It includes; step.

In the cutting process, the lens 1 is formed by the lateral cutting and the longitudinal cutting of the lens sheet 2. Even if each configuration of the rectangular annular surface 11 is formed into irregular corners in the cutting process, the optical function of the first optical surface and the second optical surface 12, 13 is not affected. It also eliminates the need for an irregular globular polish of rectangular toroidal surfaces to effectively reduce manufacturing costs. In the assembling step, the slot 33 is provided at each corner of the lens holder 31 of the lens module 3 and the rectangle of the rectangular annular surface 11 for easy assembling step as shown in FIGS. 5 and 6. Corresponds to the configuration. Alternatively, in Figures 7 and 8 bumps 34 are provided on four sides of the lens base 31 to form slots 33 between two adjacent bumps 34 for alignment and easy assembly.

Second Embodiment

10 and 11, the rectangular optical glass lens 1 having both sides convex according to the present invention includes a first optical surface 12, a second optical surface 13, and an annular surface 11. The focal length of the lens is 1.796 mm in the present invention. 12 and 13, when assembled with the lens module 3, the lens is applied to a CMOS sensor whose diagonal of the CMOS sensor is smaller than 1/10 ". In the embodiment of the present invention, the first optical surface And the relevant parameters at the second optical surface are designed by the aspherical equation (1) and shown in Table 2.

12 and 13, the lens module 3 includes a rectangular optical glass lens 1, a lens base 31, and an aperture 32. The rectangular annular surface 11 is fixed to the lens base 31 and the first optical surface 12 and the second optical surface 13 are focused on light entering the aperture 32 of the CMOS sensor (not shown). It is an optical area that fits.

The manufacturing method of the rectangular optical glass lens 1 of the embodiment of the present invention is similar to the first sealing example shown in FIG. However, both surfaces of the cavity surface 50 of the mold 5 are convex. This means that not only the cavity surface 50 of the upper mold 51 but also the lower mold 52 is a concave aspherical surface, and the lens 1 to be pressed and molded becomes an aspherical lens having both surfaces convex. The lens 1 of the present invention has an assembly design similar to that of the first embodiment. Unpolished irregular corners are mounted inside the corresponding slots 33 of the lens module 3, and the assembly accuracy is not affected. The cost is also reduced by omitting the policy step.

Third embodiment

As shown in Fig. 17, the rectangular optical glass lens 1 is manufactured by being molded together with the projection 54 as shown in Figs. In the conventional molding process of glass lenses, the air inside the mold cavity is generally released by vacuum pumping to avoid bubbles caused by residual air in the mold cavity which may adversely affect lens accuracy. In the molding process, the glass preform presses the lower mold and the air inside the mold cavity becomes difficult to discharge. There are several techniques that can solve the problem in the molding process of a single cavity mold. However, air release is still a problem in multi-cavity glass molding processes.

9 and 14, the rectangular optical glass lens 1 of the present invention can be a convex-concave, double-sided convex or other type of aspherical lens as in the first and second embodiments, and the process of the manufacturing method is Similar to the process of the first embodiment. A plurality of protrusions 54 having similar heights in the mold 5 of the embodiment are provided around the aspherical cavity surface 50 of the upper mold and the lower mold cores 51, 52.

The upper mold 51 may be provided without the protrusion 54. The provisioning method and the number of protrusions 54 depend on the number of cavity surfaces 50 and the calculation result (experimental result). During the vacuum pumping process in the initial stage of the molding fixation, the air in the mold cavity is discharged from the gaps around the protrusions 54 formed by the height difference to achieve a high discharge efficiency δ. As can be seen in FIG. 16, the corresponding groove 15 is formed in the lens sheet 2 by each projection 54. As shown in FIG. After the lens sheet 2 is cut, each groove 15 will still be left on the annular surface of the rectangular optical glass lens 1 according to the position of the projection 54 or the cutting line as shown in FIG. will be. However, the groove 15 does not affect the annular plane accuracy and size of the rectangular optical glass lens in the step of assembling with the lens holder 31.

Therefore, the present invention has the disadvantages of the air discharge slot provided in the conventional mold to guide the projection to the annular surface of the lens and the disadvantage that the accuracy and size of the annular surface 11 of the rectangular optical glass lens 1 are affected by the protrusion. It is to solve. By the mold 5 provided with the projections 54, the yield rate of the lens 1 according to the present invention is increased and the design of the mold as described above will not affect the assembly step.

Fourth Embodiment

Referring to FIG. 20, in the embodiment of the present invention, the rectangular optical glass lens 1 is formed by a mold having bar-shaped protrusions in FIG. The above-described design is suitable for the mold 5, which is difficult to discharge air because the mold is deeper and the cavity surface 50 has a larger diameter.

In order to increase the air discharge efficiency δ, the projection 54 of the third embodiment is replaced by the bar-shaped projection 55 and is provided in the outer ring surrounding the cavity surface 50 of the lower mold and / or the upper mold 51. . As shown in FIG. 18, the bar-shaped protrusion 55 extends from the perimeter 56 of the cavity surface 50 to the perimeter 57 of the mold 5. The manufacturing method of the above preferred embodiment is the same as in the previous embodiment. Referring to FIG. 19, the molded lens sheet 2 includes a bar protrusion 55 and a strip groove 14 corresponding thereto. Referring to FIG. 20, after cutting, the rectangular optical glass lens 1 includes a first optical surface 121, a second optical surface 13, and a rectangular annular surface 11. There are also some strip grooves 14 provided in the rectangular annular surface 11, which do not affect the size and accuracy of the annular surface. Therefore, the mold 55 having at least one bar-shaped protrusion 55 improves the yield rate of the lens 1 and has no negative influence in the assembly process.

Fifth Embodiment

Referring to Fig. 22, in the embodiment of the present invention, the rectangular optical glass lens 1 is formed by a mold having a plurality of inverted V-shaped strip protrusions. The inverted V-shaped strip projections 58 having a similar height are provided on the cavity surface 50 at predetermined intervals in the longitudinal and / or transverse directions, and the air in the cavity is formed of the rectangular glass blank 4 and the inverted V-shaped strip projections. The gap formed by the height difference between 58) is released during the mold forming process to improve the air discharge efficiency. As shown in Fig. 22, the inverted V-shaped strip protrusion 58 forms a corresponding V-shaped cutting groove 16 in the lens sheet 2, and the cutting groove 16 is a cutting line of the lens sheet 2. It can be used as part of. The lens sheet 2 may be cut into a plurality of rectangular lenses 1 having the same size.

As shown in Fig. 23, the above-described inverted V-shaped strip protrusion 58 is provided in a discontinuous structure. This means that a plurality of V-shaped strip protrusions 58 are provided discontinuously. A gap 59 is formed between two adjacent reverse V-shaped strip protrusions 58 to improve the air discharge efficiency. The molded lens sheet 92 as shown in Fig. 24 includes a plurality of discontinuous V-shaped cutting grooves 17 which can work with a cutting lens, which facilitates the cutting operation of the lens.

For reference, the specific embodiments of the present invention are only presented by selecting the most preferred embodiments to help those skilled in the art from the various possible examples, the technical spirit of the present invention is not necessarily limited or limited only by this embodiment. In addition, various changes, additions, and changes are possible within the scope of the technical spirit of the present invention, as well as other equivalent embodiments.

Figure 1 shows a rectangular optical glass lens according to the prior art,

Figure 2 shows a lens sheet according to the prior art,

Figure 3 shows the front of the lens according to the present invention,

4 shows the side of FIG.

Figure 5 shows the side of the lens applied to the lens module by the present invention,

6 illustrates the front of FIG. 5;

Figure 7 shows another view of the lens applied to the lens module,

FIG. 8 illustrates the front of FIG. 7;

9 is a flowchart showing a manufacturing process according to the present invention,

10 is a front view of another embodiment according to the present invention,

11 illustrates the side of FIG. 10,

12 illustrates a side of another embodiment of the present invention applied to a lens,

Fig. 13 shows the front of Fig. 12,

Figure 14 shows a lower mold of another embodiment according to the present invention,

Figure 15 shows an upper mold of another embodiment according to the present invention,

Figure 16 shows a lens sheet of another embodiment according to the present invention,

Figure 17 shows a perspective view of another embodiment according to the present invention,

Figure 18 shows a lower mold of another embodiment according to the present invention,

Figure 19 shows a lens sheet of another embodiment according to the present invention,

20 is a perspective view of another embodiment according to the present invention,

Figure 21 shows a lower mold of another embodiment according to the present invention,

Figure 22 shows a lens sheet of another embodiment according to the present invention,

Figure 23 shows another mold of another embodiment according to the present invention,

Figure 24 shows another lens sheet of another embodiment according to the present invention.

Claims (7)

Claims [1] A rectangular optical glass lens formed by cutting a lens sheet having a plurality of lens structures manufactured by a rectangular glass blank heated and pressed between an upper mold and a lower mold of a multiple cavity mold. An aspherical first optical surface provided on one side of the lens; An aspherical second optical surface provided on the opposite side of the first optical surface; And A rectangular annular surface provided around the first optical surface and the second optical surface, wherein the first optical surface and the second optical surface are optical regions of the rectangular optical glass lens, and the rectangular annular surface is a non-optical region. The rectangular optical glass lens, characterized in that the rectangular shape having four corners, the rectangular annular surface is formed by the cutting of the lens sheet. The method of claim 1, And the first optical surface and the second optical surface are formed by a convex aspheric surface and a concave aspheric surface. The method of claim 1, A rectangular optical glass lens, wherein the first optical surface and the second optical surface are two convex aspherical surfaces. The method of claim 1, At least one surface of the rectangular circumference includes at least one groove, wherein the groove is formed and molded on the lens sheet due to an air discharge protrusion provided around the cavity of the upper or lower mold. Rectangular optical glass lens. The method of claim 1, At least one surface of the rectangular circumference includes at least one strip groove, the strip groove being formed around the cavity of the upper or lower mold bar-like protrusions provided by the lens sheet Rectangular optical glass lens, characterized in that formed on the top and molded. The method of claim 1, The lens sheet includes a plurality of V-shaped cutting grooves at predetermined intervals in the longitudinal axis and / or the horizontal axis direction, and the V-shaped cutting grooves are formed due to the air discharge reverse V-shaped strip protrusions provided around the cavity of the upper or lower mold. Rectangular optical glass lens, characterized in that formed on the lens sheet and molded. The method of claim 6, The V-shaped cutting groove formed in the lens sheet is a rectangular optical glass lens, characterized in that used as a cutting line to form a right angle (right angle) with a rectangular shape of a rectangular annular surface.

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