KR20240040974A - Method and system for manufacturing multi-function HOE using hologram replication technology - Google Patents

Abstract

The present invention relates to a method of manufacturing a multi-functional HOE using hologram replication technology, comprising the steps of manufacturing single-function HOEs each having different optical characteristics;
manufacturing a master HOE by arranging the manufactured single-function HOEs into a structure optimized for the purpose of use;
It is characterized by comprising the step of producing a multi-functional HOE by recording the interference pattern of the master HOE on a photosensitive medium through hologram replication technology.
In addition, the present invention relates to a multi-functional HOE manufacturing system using hologram replication technology,
Single-function HOE production department (10);
Master HOE Production Department (20);
It consists of a hologram replication unit (30),
According to the present invention, there is a remarkable effect of being able to manufacture a multi-functional HOE and configure a system so that one HOE can perform two or more optical functions.

Description

{Method and system for manufacturing multi-function HOE using hologram replication technology}

The present invention relates to a method and system for manufacturing holographic optical elements (HOE) that can perform complex functions based on holography.

The present invention relates to a method and system for manufacturing a multi-functional HOE so that one HOE can perform two or more optical functions.

Unlike conventional multi-function HOE production systems, the present invention manufactures single-function HOEs with different optical characteristics, arranges these HOEs in a structure corresponding to the user's purpose to produce a master HOE, and uses hologram replication technology to create a single HOE. This relates to a manufacturing method and system for a multi-functional HOE that makes it very easy to design and modify the optical function of the multi-functional HOE and then remanufacture it.

The present invention relates to a multi-functional HOE manufacturing and system that requires a relatively simple optical system since the multi-functional HOE manufacturing process requires only an optical system for manufacturing a single-functional HOE.

The multi-function HOE manufactured in the present invention, unlike conventional HOEs that perform complex functions, relates to a method and system for manufacturing a multi-function HOE without crosstalk between areas that perform different optical roles within a single HOE. will be.

The multi-function HOE manufactured in the present invention relates to a method and system for manufacturing a multi-function HOE without noise caused by a mask by not using a mask during the manufacturing process, unlike conventional HOE manufacturing methods that perform complex functions.

HOE is a technology that uses the principles of holography and is a type of diffractive optical element (DOE). It is in the spotlight as a useful technology that can replace heavy and complex optical elements. HOE is a technology that can replace heavy and complex optical elements by Because it can implement a variety of functions, it can be a mirror, lens, or directional diffuser. Therefore, HOE is widely applied in many fields such as holographic memory, holographic projection screen, holographic printer, and 3D head-mounted display (HMD). As an example of conventional patent technology, registration number 10-2264211 discloses an AR holographic display using an optical waveguide and HOE. Additionally, Publication No. 10-2021-0102344 discloses a method for manufacturing a holographic optical element (HOE) provided for projection in a projection system. Such holographic optical elements, projection devices, spectacle lenses for data glasses and such data glasses.

HOE is a type of diffractive optical element (DOE). Unlike general optical elements that collect or spread light depending on the curvature or shape of the optical element, or change the optical path of light, HOE relies on the principle of diffraction. It performs an optical function by diffracting light and reconstructing the wavefront.

Meanwhile, multi-function HOE has the advantage of simplifying the complexity and size of the system by recording multiple optical characteristics as interference patterns in a single photosensitive material so that one HOE can perform two or more optical functions. Therefore, very active research is being conducted for applications in fields such as augmented reality (AR), head-mounted display (HMD), and digital holography microscopy (DHM), which require new optical devices or systems depending on the wavelength of light or imaging characteristics. It is becoming.

However, there is a disadvantage that a complex optical system setup is required to manufacture a multi-function HOE through a single interference pattern recording process. As the number of optical functions that a multi-function HOE must perform increases, the optical system becomes more expensive. Complexity also increases.

In addition, this increase in the complexity of the optical system acts as a significant disadvantage when redesigning and modifying the optical function performance area of the multi-function HOE and then remanufacturing it.

Additionally, in order to overcome these shortcomings, there is a method of manufacturing a multi-functional HOE by repeating the process of controlling and adjusting the area where the interference pattern will be recorded through masking on a single photosensitive medium several times.

However, the method using masking has the disadvantage of generating unwanted noise when using HOE because the diffraction pattern generated by the mask placed on the photosensitive medium is also recorded in the HOE when recording the interference pattern.

In HOE's replication technology, the master hologram used for optical replication is generally a photopolymer or silver halide that stores the interference pattern information between the reference beam and the object beam, which is composed of high-coherence light such as a laser. ) is produced by recording on the same photosensitive hologram recording medium.

In addition, the replication of HOE is accomplished through the process of bringing the radiator and the covered object into close contact or proximity and then incident a reference beam on them. At this time, the laser beam, which is the light source, mainly uses a plane beam as the incident beam.

Hologram replication is a technology that records the interference pattern between the incident beam and the diffracted beam diffracted from the master hologram on a photosensitive medium.

Hologram replication technology can be broadly classified into transparent and reflective types depending on the method by which the master hologram is produced.

Transmissive hologram replication technology records the interference pattern between the incident beam and the diffracted beam diffracted by the radiator on the radiator (hologram recording medium) after the incident beam first passes through the radiator (master hologram).

Reflective hologram replication technology records the characteristics of the wavefront reflected from the radiator (master hologram) on the radiator after the incident beam first passes through the radiator (hologram recording medium). At this time, the incident beam serves as a reference beam and the reflected beam serves as an object beam.

The purpose of the present invention is to solve the problems of the prior art as described above and to provide a method and system for manufacturing a multi-functional HOE using hologram replication technology.

Another object of the present invention is to manufacture single-function HOEs with different optical characteristics, arrange these HOEs in a structure corresponding to the purpose of use, produce a master HOE, and produce a single multi-function HOE through hologram replication technology. The goal is to provide a manufacturing method and system for a multi-functional HOE that is very easy to design and modify the optical function of the multi-functional HOE and then remanufacture through the process.

Another object of the present invention is to provide a method and system for manufacturing a multi-function HOE in which the size and position of areas that perform two or more different optical functions can be freely set according to the user's intention. .

Another object of the present invention is to provide a multi-functional HOE manufacturing process and a system with a relatively simple optical system structure that requires only an optical system for manufacturing a single-functional HOE in the multi-functional HOE manufacturing process.

Another object of the present invention is to provide a method and system for manufacturing a multi-function HOE without crosstalk between areas performing different optical roles within the multi-function HOE.

Another object of the present invention is to provide a method and system for manufacturing a multi-function HOE without noise caused by a mask that may occur when manufacturing the multi-function HOE.

To achieve this purpose, the method and system for manufacturing multi-functional HOEs using hologram replication technology according to the present invention manufactures single-function HOEs with different optical characteristics and then arranges the manufactured single-function HOEs into a structure optimized for the purpose of use. It is characterized by producing a master HOE and recording the interference pattern of the master HOE on a photosensitive medium through hologram replication technology to produce a multi-functional HOE.

The multi-functional HOE manufacturing method and system is characterized by being composed of a single-function HOE manufacturing unit, a master HOE manufacturing unit, and a hologram replication unit.

In the multi-function HOE manufacturing method and system, the single-function HOE manufacturing unit considers the number of optical characteristics (functions?) to be performed by the final result, the multi-function HOE, and manufactures a single-function HOE corresponding to that number.

The master HOE manufacturing unit of the multi-functional HOE manufacturing method and system is characterized in that the master HOE is manufactured by arranging single-function HOEs that perform different optical functions manufactured in the single-function HOE manufacturing unit according to the user's purpose.

The hologram replication part of the multi-functional HOE manufacturing method and system is characterized in that it replicates the interference pattern of the master HOE onto a photosensitive medium using hologram replication technology to produce a multi-functional HOE in the form of a single film.

The method and system for manufacturing a multi-function HOE manufactures a multi-function HOE through an array of single-function HOEs that perform different optical functions, so the process of manufacturing, designing, modifying, and then remanufacturing the multi-function HOE is very easy. .

The method and system for manufacturing a multi-function HOE requires only an optical system for manufacturing a single-function HOE, and is therefore characterized in that it is possible to manufacture a multi-function HOE and configure the system with a relatively simple optical system.

The multi-function HOE manufacturing method and system considers the number of optical functions to be performed by the multi-function HOE, manufactures single HOEs corresponding to each optical function, and then arranges them according to the purpose of use to produce a master HOE, resulting in the final result. When using a multi-function HOE, there is no crosstalk between areas that perform different optical functions.

The method and system for manufacturing a multi-function HOE is characterized by manufacturing a HOE without noise caused by a mask by not using a mask in the process of manufacturing a multi-function HOE.

According to the present invention, it is possible to manufacture a multi-function HOE and configure a system so that one HOE can perform two or more optical functions.

In addition, the multi-function HOE produced according to the present invention is different from the conventional multi-function HOE production system, where single-function HOEs with different optical characteristics are manufactured, and then these HOEs are arranged according to the user's purpose to produce a master HOE and replicate the hologram. By manufacturing a single multi-functional HOE through technology, it is possible to manufacture a multi-functional HOE and configure a system that is very easy to manufacture, design, modify, and then remanufacture.

In addition, according to the present invention, since only an optical system for manufacturing a single-function HOE is required in the process of manufacturing a multi-function HOE, it is possible to manufacture a multi-function HOE and configure a system with a relatively simple optical system structure.

In addition, unlike conventional HOEs that perform multiple functions, the multi-function HOE manufactured in the present invention can be manufactured without crosstalk between areas that perform different optical roles within a single HOE.

Unlike conventional HOEs that perform multiple functions, the multi-function HOE manufactured in the present invention does not use a mask during the manufacturing process, so it has the remarkable effect of being able to construct a manufacturing method and system for a multi-function HOE without noise caused by a mask. .

1 is a block diagram of the system of the present invention.
Figures 2a, b are optical schematic diagrams for fabricating a single-function HOE of the system of the present invention.
Figures 3a and b show a single-function HOE sample fabrication unit manufactured using the optical design of Figures 2a and b.
Figures 4a and b show the multi-functional HOE master production unit of the present invention system.
5 is an optical schematic for fabricated master replication of the system of the present invention.
Figures 6a and 6b are the schematic diagram of Figure 5, showing an optical fabrication unit for master replication.
Figure 7 is an example of a replicated multi-functional HOE sample.
Figure 8 is a basic conceptual diagram of conventional hologram replication.

The present invention relates to a method of manufacturing a multi-functional HOE using hologram replication technology, comprising the steps of manufacturing single-function HOEs each having different optical characteristics;

manufacturing a master HOE by arranging the manufactured single-function HOEs into a structure optimized for the purpose of use;

It is characterized by comprising the step of producing a multi-functional HOE by recording the interference pattern of the master HOE on a photosensitive medium through hologram replication technology.

In addition, the present invention relates to a multi-functional HOE manufacturing system using hologram replication technology,

Single-function HOE production department (10);

Master HOE Production Department (20);

It is characterized by being composed of a hologram replication unit (30).

In addition, the single-function HOE manufacturing unit 10 manufactures a single-function HOE according to the number of optical characteristics to be performed by the final result, a multi-function HOE,

The master HOE manufacturing unit 20 is characterized in that it manufactures a master HOE by arranging the single-function HOEs that perform different optical functions manufactured in the single-function HOE manufacturing unit 10 according to the user's purpose.

The present invention will be described in detail with the accompanying drawings as follows.

Figure 1 is a schematic diagram of the manufacturing process of a multi-functional HOE using the hologram replication technology of the present invention.

As shown in Figure 1, the multi-functional HOE manufacturing system in the present invention consists of a single-function HOE manufacturing unit, a master HOE manufacturing unit, and a hologram replication unit.

The single-function HOE production department in Figure 1 considers the number of optical functions that the final multi-function HOE must perform and manufactures the number of single-function HOEs.

The single-function HOE production department in Figure 1 produces three single-function HOEs as examples.

The master HOE production department in Figure 1 manufactures the master HOE by arranging the HOEs manufactured from the single-function HOE, taking into account the positions of areas that must perform different optical functions within the final multi-function HOE.

In the hologram replication unit of Figure 1, the interference pattern recorded in the master HOE produced in the master HOE production unit is copied to a photosensitive medium using hologram replication technology to produce the final complex functional HOE.

Figure 2 is a conceptual diagram of an optical system for a single-function HOE manufacturing unit in the multi-functional HOE manufacturing method and system using the hologram replication technology of the present invention.

In Figure 2, M (Mirror) is a mirror, SF (Spatial Filter) is a spatial filter, and BS (Beam Splitter) is a beam splitter.

In Figure 2, the laser beam output from the laser is divided into a reference beam and a signal beam through a beam splitter (BS) located on the optical path.

As shown in FIG. 2, the reference beam and the signal beam pass through each optical path and record an interference pattern on the photosensitive medium. At this time, the wavefront shape of the reference beam and the signal beam is a spherical wave.

The incident angle and distance of the reference beam and signal beam on the holographic recording medium are set considering the characteristics of the system in which the HOE will be used.

Figures 2(a) and (b) are examples of optical designs for manufacturing single-function HOEs. In this example, single-function HOEs with relatively short projection distances can be fabricated through simple adjustment of optical elements in each optical setup (Figure 2(a) )) and a single-function HOE (Figure 2(b)) with a relatively long projection distance can be fabricated.

Figure 3 shows single-function HOE samples actually fabricated using the optical system of Figure 2.

Figure 3(a) shows the HOE, which is a monochromatic light source with a short projection distance, manufactured with a G laser with a reference beam of 0.27 mW and a signal beam of 0.28 mW with an exposure time of 300 s.

Figure 3(b) shows an HOE manufactured with a monochromatic light source G laser with a long projection distance, a reference beam of 0.18 mW, a signal beam of 0.19 mW, and an exposure time of 300 s.

Figure 4 shows an example of the shape and optical characteristics of the master HOE in the multi-functional HOE manufacturing method and system using the hologram replication technology of the present invention.

Figure 4(a) is an example of a master HOE and shows two single-function HOEs, each with different optical characteristics, attached to a glass plate.

Figure 4(b) is an example of the optical characteristics of the master HOE and expresses that the imaging depth for information on a light source input at a fixed position is determined in accordance with the optical characteristics of each HOE constituting the master HOE.

Figure 5 is a conceptual diagram of an optical system for replicating a master HOE in the method and system for manufacturing a multi-function HOE using the hologram replication technology of the present invention. Through this process, the final multi-function HOE is manufactured.

In the picture, M (Mirror) is a mirror, SF (Spatial Filter) is a spatial filter, and Iris is a laser aperture.

The system shown in Figure 5 is a reflective hologram replication technology. As shown in the figure, laser beams output from three laser light sources, R, G, and B, pass through optical elements located on each optical path and are irradiated onto a photosensitive medium. .

Like the principle of reflective hologram replication technology, the incident beam first passes through a photosensitive medium (hologram recording medium), and then the characteristics of the wavefront reflected from the master HOE are recorded on the photosensitive medium. At this time, the incident beam serves as a reference beam and the reflected beam serves as an object beam.

Figure 6(a) is a hologram replication optical system constructed based on the design diagram of Figure 5.

Figure 6(b) is an optical system for finding an optimized diffraction pattern before replicating the master in the process of Figure 4.

Figure 7 is an example of the final multi-functional HOE result replicated from the master HOE.

10: Single-function HOE production department
20: Master HOE Production Department
30: Hologram replication department
1: Laser 2: Shutter
3 : BS 4 : SF
5: IRIS 6: M (mirror)
7 : lens 8 : Hoe
9:Glass 11:MASTER
12: DM(Dichroic Mirror)

Claims (3)

Manufacturing single-function HOEs each having different optical characteristics;
manufacturing a master HOE by arranging the manufactured single-function HOEs into a structure optimized for the purpose of use;
A method of manufacturing a multi-function HOE using hologram replication technology, comprising: manufacturing a multi-function HOE by recording the interference pattern of the master HOE on a photosensitive medium through hologram replication technology. Single-function HOE production department (10);
Master HOE Production Department (20);
A multi-functional HOE production system using hologram replication technology, characterized in that it consists of a hologram replication unit (30). The method of claim 2, wherein the single-function HOE manufacturing unit (10) manufactures the single-function HOE according to the number of optical characteristics to be performed by the final result, the multi-function HOE, and the master HOE manufacturing unit (20) manufactures the single-function HOE. A multi-function HOE production system using hologram replication technology, characterized in that a master HOE is produced by arranging single-function HOEs that perform different optical functions produced in the production unit 10 according to the user's purpose.