JPH07122688B2 - Optical element with carrier - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an optical element with a carrier in which a glass material heated to a moldable temperature is integrally joined with a carrier equipped with a function other than a carrying function.

[Prior Art] Recently, molding means for molding optical elements such as lenses, prisms, and filters by press molding without performing polishing or the like has been adopted. The molding means conveys the glass material that has been heat-softened to a moldable state between the upper and lower molds for molding through a carrier linked to a transporting device, stops it, and then press-molds it through the upper and lower molds for molding. A shaped optical element is obtained.

However, in this type of molding means, there is a problem that the carrier is fused together with the high temperature glass material at the time of molding. A technique has been devised in which the carrier and the optical element are integrally molded by also having a function of holding and assembling at the time or a function of regulating an outer diameter at the time of molding. Such an optical element integrally molded with the carrier is referred to as an optical element with a multifunctional carrier, and the configuration of such an optical element with a multifunctional carrier is disclosed in JP-A-60-63743.

That is, the technology disclosed in JP-A-60-63743 is
By integrally forming an optical element heated to a moldable temperature and an optical element carrying carrier having an assembly holding portion of this optical element or an outer diameter regulating portion at the time of molding, during press molding The work for assembling the optical element and the centering work for assembling the optical element can be facilitated.

[Problems to be solved by the invention]

However, the above-mentioned conventional technique has the following problems. That is, immediately after press-molding the glass material that has been subjected to the heat-softening treatment, the molded optical element and the carrier having multiple functions are integrally combined with each other with a sufficient bonding force. During the cooling process, the take-out process, the mounting process and the use process, there is a change with time between the optical element and the carrier, which may cause looseness between the optical element and the carrier over time or the optical element may come off the carrier. There was a big problem that it would end up.
Further, in the above-mentioned prior art, since no consideration is given to the coefficient of thermal expansion between the glass material of the optical element and the carrier constituent member, when the coefficient of thermal expansion between both materials and members is greatly different, molding is performed. There has been a serious problem that the optical element is cracked or the optical functional surface is distorted in the subsequent cooling process.

The present invention has been made in view of the above-mentioned problems of the prior art, and assures the coupling force between the optical element and the carrier, as well as a high optical element without causing cracks or distortion. An object of the present invention is to provide an optical element with a carrier capable of exhibiting a function of performance.

[Means for Solving the Problems]

The present invention is provided with a glass material heated to a moldable temperature, an assembly holding portion of an optical element after molding, and an outer diameter restricting portion at the time of molding the glass material, and the outer diameter restricting portion is provided with the optical material after molding. The carrier for transportation provided with an oxide film for strengthening the bond with the element is integrally joined and configured at the time of press molding.

[Action]

In the above configuration, when the heated glass material is molded, the molded optical element and the carrier are strongly bonded to each other due to mutual diffusion of the oxides of the both, and it is possible to reliably prevent looseness and omission of the optical element. When the material of the carrier in the above is made of a material that is substantially the same as or slightly smaller than the coefficient of thermal expansion of glass, distortion and cracking of the optical element can be reliably prevented.

〔Example〕

Examples of the present invention will be described below with reference to the drawings. Prior to the description of specific examples, a press molding apparatus for press molding an optical element according to the present invention will be described with reference to FIG.

In the figure, reference numeral 1 designates an upper mold, which is fixed to an upper plate 2 of the apparatus main body. Denoted at 3 is a lower mold which is arranged on the same line as the upper mold 1 so as to be slidable in a direction in which the lower mold 4 comes into contact with and separates from the upper mold 1 through a lower plate 4 fixedly provided in the apparatus main body. Is held. The upper plate 2 and the lower plate 4 are connected to each other by a connecting member (not shown) so that the distance and position between them do not change.

Reference numeral 5 denotes a transfer arm for loading and unloading the glass material 6 which is the object to be molded to and from the molding point between the upper and lower molding dies 1 and 3, and the glass material 6 is molded in a state in which it is placed on the carrier 7. It is set and configured so that it can be carried in and out at points. Reference numeral 8 indicates a heater for heating the glass material 6 to a moldable temperature (moldable state) before the glass material 6 is carried into a molding point. The heater 8 constitutes a heating furnace 9. There is. The temperature in the heating furnace 9 can be set to a predetermined temperature by a temperature measuring device and a temperature control device (not shown). Molding room
The periphery of 10 is composed of an inner wall 11 made of quartz glass,
Care is taken not to oxidize even when the temperature inside the molding chamber 10 becomes high. Further, the molding chamber 10 is connected in communication with the atmosphere gas supply device 12, and is filled with the oxidation-preventing nitrogen gas, inert gas, or reducing gas supplied from the atmosphere gas supply device 12. ing.

The carrier 7 on which the glass material 6 is placed and supported is set and configured so as to have various functions other than the carrying function, that is, a function of assembling and holding a molded product and a function of regulating an outer diameter at the time of molding. When the glass material 6 heat-treated in the heating furnace 9 is press-molded through the upper and lower molds 1 and 3, the carrier 7
The optical element after molding and the optical element after molding are integrally joined. The specific configuration of the carrier 7 and the coupling configuration of the carrier 7 and the optical element will be specifically described in the following examples.

(First Embodiment) FIGS. 2a, 2b, 3 and 4 show a first embodiment of the optical element 20 with a carrier according to the present invention.
a and b are a plan view and a front sectional view showing the structure of the carrier 7, FIG. 3 is a front sectional view showing the state of the optical element with a carrier 20 after press molding, and FIG. 4 is a press molded optical element with a carrier. FIG. 20 is a front sectional view showing an assembled state of 20.

As shown in FIGS. 2a and 2b, the carrier is composed of a cylindrical carrier body 7a and a flange-shaped carrier holding ear 7b. A hole 21 and a support step 22 for mounting and supporting the glass material 6 (see FIG. 1) which is a workpiece is formed in the shaft center portions of the carrier body 7a and the carrier holding ear 7b. The glass material 6 is placed and supported in the hole 21 while being in contact with the support step portion 22. The hole 23 of the support step portion 22 functions as a hole for transmitting light at the time of assembly. Further, the inner peripheral surface of the hole 21 is coated with an oxide film and functions as an outer diameter restricting portion when the glass material 6 is molded. Four (not limited to four) holes 24 for assembling are provided in the flange-shaped carrier holding ear portion 7b so as to be arranged. Assembly hole 24
As shown in FIG. 4, is engaged with a carrier locking pin 26 fixed to a holding frame 25 for holding the optical element 6a integrally formed with the carrier 7 after molding. The hole 24 and the carrier locking pin 26 are engaged with each other when assembled, and the optical element 6a and the holding frame are
The axis of 25 is automatically aligned. The carrier 7 is made of a material having a coefficient of expansion which is substantially the same as or slightly smaller than the expansion coefficient of the glass material 6, and the allowable range of the difference in thermal expansion coefficient depends on the diameter and shape of the optical element 6a.

As described above, a coating film 35 made of an oxide is deposited on the lower part (not limited to the lower part) of the inner peripheral surface of the hole 21 of the carrier, and as shown in FIG. When the glass material 6 is press-molded via the and 3, the optical element 6a is molded, the coating 35 and the glass material 6 can be firmly bonded through the bonding.

That is, since most of the glass material 6 is composed of an oxide, when the glass material 6 is brought into contact with the oxide film 35 at a high temperature, mutual diffusion occurs and the glass material 6 is firmly bonded to each other. It is a thing. The coating film 35 may be formed by oxidizing the carrier 7 itself, or may be formed by ceramic spraying, vapor deposition, or another method. The oxide film used in this example was formed of three kinds of Fe ₂ O ₃ , SiO ₂ , and Al ₂ O ₃ .

Next, the operation based on the above configuration will be described. The glass material 6 placed on the carrier is heat-softened to a moldable state in the heating furnace 9 via the transfer arm 5 as shown in FIG. It is transported to the molding point.

Next, the lower die 3 is moved upward, and the glass material 6 placed on the multi-functional carrier 7 is press-formed through the upper and lower dies 1 and 3 into an optical element 6a having a predetermined shape. During this press molding,
The upper and lower surfaces of the glass material 6 are regulated by the molding surfaces of the upper and lower molds 1 and 3, and the outer peripheral surface is regulated by the inner peripheral surface of the hole 21 of the carrier 7 for molding. Further, for molding, the optical film with carrier in which the oxide film 31 on the inner peripheral surface of the hole 21 and the oxide of the glass material 6 are combined by mutual diffusion to firmly bond the carrier 7 and the optical element 6a together. The element 20 can be molded.

Further, since the material of the multi-functional carrier 7 is made of a material that is almost the same as or slightly smaller than the thermal expansion coefficient of glass, even if a change with time occurs after molding, distortion or cracking of the surface of the optical element 6a does not occur. The occurrence can be reliably prevented. Furthermore, as shown in FIG. 4, when the optical element 20 with a multifunctional carrier is held by the holding frame 25, the hole 24 for mechanical assembly and the locking pin 26 are mechanically assembled without using an adhesive material. Since they are automatically aligned and assembled and held by engaging, accurate and reliable holding is possible.

〔The invention's effect〕

As described above, according to the present invention, when the optical element and the carrier are integrally bonded and configured, the optical element and the carrier can be firmly bonded, and the post-process or assembly after molding, It is possible to reliably prevent looseness and omission of the optical element during use. Further, when the material of the carrier is made of a material having a coefficient substantially equal to or smaller than the coefficient of thermal expansion of glass, it is possible to reliably prevent distortion and cracking of the optical element.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a schematic configuration of a molding apparatus for molding an optical element with a carrier according to the present invention, FIGS.
FIG. 4 and FIG. 4 show a first optical element with a carrier according to the present invention.
It is an explanatory view showing an example of. 1,3 …… Upper and lower molds 6 …… Glass material 6a …… Optical element 7 …… Carrier 35 …… Coating

Claims (2)

[Claims] 1. A glass material heated to a moldable temperature,
For transportation, which is provided with an assembly holding portion for the molded optical element and an outer diameter regulating portion at the time of molding the glass material, and which is provided with an oxide film for strengthening the coupling with the molded optical element. An optical element with a carrier, characterized in that the carrier and the carrier are integrally joined during press molding. 2. The optical element with a carrier according to claim 1, wherein the carrier for transportation is made of a material having a coefficient of thermal expansion substantially equal to or smaller than that of the glass material. .