KR20080098255A - A beam conversion apparatus - Google Patents

Abstract

A beam conversion device is provided to maximize collection efficiency and illuminance uniformity by converting an irradiated two-dimensional beam as the one-dimension beam. In a beam conversion device, a first lens(110) refracts an inputted two-dimensional beam so that the length of the first axis direction of inputted two dimension beam is expanded. A beam converting lens(130) condenses the two-dimensional beam to one-dimensional beam far from the predetermined intervals in the second axis direction so that the length of the first axis direction is expanded and crossed with the second axis direction. A second lens(120) is at the front side or the backplane of above beam converting lens and controls the divergence angle to which the length of the first axis direction is expanded.

Description

A beam conversion apparatus

1A is a view showing a display device using the beam conversion device of the present invention.

Figure 1b is a view showing one side and the other side of the beam conversion apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a table showing magnification characteristics when an input two-dimensional beam is magnified in a first axis direction through a first refractive surface of the present invention. FIG.

3A and 3B are graphs showing an increase in illuminance uniformity of a beam when it passes through the beam conversion apparatus of the present invention.

4A is a diagram illustrating one surface of a beam conversion apparatus according to an embodiment of the present invention illustrated in FIG. 1B, and FIG. 4B is a diagram illustrating actual implementation data of the beam conversion apparatus illustrated in FIG. 4A.

FIG. 5A is a diagram illustrating one surface of a beam conversion apparatus according to another embodiment of the present invention, and FIG. 5B is a diagram illustrating actual implementation data of the beam conversion apparatus shown in FIG. 5A.

FIG. 6A is a diagram showing one surface of a beam conversion apparatus according to another embodiment of the present invention, and FIG. 6B is a diagram illustrating actual implementation data of the beam conversion apparatus shown in FIG. 6A.

7A and 7B illustrate the structure of an optical modulator, which is one of the incident objects of the one-dimensional beam converted by the beam conversion apparatus of the present invention.

7C and 7D are diagrams for explaining the light modulation principle in the light modulator of FIG. 7A.

<Description of the symbols for the main parts of the drawings>

110: first lens 115: first refractive surface

120: second lens 125: second refractive surface

130: beam conversion lens 140: light modulator

The present invention relates to a lighting apparatus, and more particularly, to a beam converting apparatus for converting a two-dimensional beam into a one-dimensional beam.

Recently, various apparatuses and methods for efficiently concentrating a beam irradiated from a light source have been proposed while an imaging apparatus, a projection system, and the like are miniaturized. In particular, technology for embedding an imaging device or a projection system inside a small digital device (eg, a mobile phone, a PMP, etc.) has been developed. For this reason, an improvement in light collection efficiency is an important problem in an optical device or an illumination device. It is becoming.

However, according to the prior art, in order to improve the light collection efficiency, a method of complexly combining a plurality of lenses that are responsible for refraction of the beam projected on the X and Y axes is used. However, attempts to improve the light collection efficiency by using a plurality of lenses as described above do not meet the recent trend of miniaturization of optical devices by increasing the volume thereof, and have a problem of lowering the precision of the manufacturing process.

Accordingly, the present invention provides a beam converting apparatus capable of maximizing the condensing efficiency and improving the illuminance uniformity of the converted one-dimensional beam in converting (condensing) the two-dimensional beam irradiated from the light source into a one-dimensional beam. It is to provide.

In addition, the present invention is to provide a beam conversion device that can be applied to a large display device as well as small digital devices such as mobile phones, PMP by simplifying the configuration of the optical device (or lighting device) and reducing the volume of the manufactured optical device will be.

Other objects of the present invention will be readily understood through the following description.

According to an aspect of the invention, the first lens for refracting the input two-dimensional beam so that the length in the first axis direction of the input two-dimensional beam; Converts the two-dimensional beam into a one-dimensional beam by condensing the length in the second axial direction orthogonal to the first axial direction of the two-dimensional beam in which the length in the first axial direction is enlarged through the first lens to one focal point at a predetermined distance. A beam conversion lens; And a second lens positioned at a front surface or a rear surface of the beam conversion lens, and configured to adjust a divergence angle of the two-dimensional beam in which the length in the first axial direction is enlarged through the first lens.

Here, the refractive surface in the first axial direction of the first lens may be an aspheric profile.

Here, the beam conversion lens may maintain the length in the first axis direction of the two-dimensional beam in which the length in the first axis direction is enlarged through the first lens. In this case, the beam conversion lens may have a curvature only in one direction surface, and one direction surface in which the curvature exists in the beam conversion lens may be a surface corresponding to the same direction as the second axis direction of the 2D beam. As the beam conversion lens, a cylinder lens may be used.

Here, the second lens may adjust the divergence angle so that the two-dimensional beam having a length in the first axial direction is extended through the first lens in parallel.

Here, one focal point at a predetermined distance from the beam conversion lens is present on the light modulator for modulating the incident beam, and the one-dimensional beam converted by the beam conversion lens may be transferred to the light modulator. At this time, the optical modulator, the substrate; An insulating layer on the substrate; A lower light reflection layer disposed on the insulating layer and reflecting or diffracting incident light; A structure layer having a central portion spaced apart from the insulating layer by a predetermined distance; An upper light reflection layer positioned on a central portion of the structure layer and reflecting or diffracting incident light; And a piezoelectric driver positioned on the structure layer and moving the central portion of the structure layer up and down.

Hereinafter, a beam conversion apparatus according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings, and the same or corresponding components are denoted by the same reference numerals regardless of the reference numerals, and redundant description thereof will be omitted. Shall be. In describing the present invention, when it is determined that the detailed description of the related well-known technology may obscure the gist of the present invention, the detailed description thereof will be omitted.

In addition, terms including ordinal numbers such as first and second to be used below may be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component. The term and / or includes a combination of a plurality of related items or any item of a plurality of related items.

When referred to herein as being "irradiated", "incident", etc. from one component to another, it may be directly irradiated or directly projected to that other component, but in the intervening through other components It will be understood that or may be entered. On the other hand, when it is referred to as "directly irradiated" or "directly entered" from one component to another, it should be understood that it does not go through other components in the middle.

The terminology used herein is for the purpose of describing particular embodiments of the invention only and is not intended to be limiting of the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. The terms "comprise" or "have" herein are intended to indicate that there is a feature, number, step, action, component, part, or combination thereof described on the specification, but one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

1A is a diagram illustrating a display apparatus using the beam conversion apparatus of the present invention. FIG. 1A is a diagram for briefly illustrating an example of a field to which the beam conversion apparatus of the present invention is applied, taking the case of a display apparatus as an example before explaining the beam conversion apparatus according to the present invention. Therefore, in the case of a color display device, a three-color light source will be used. However, in FIG. 1A, a case where an image is implemented on one screen from one light source will be briefly described. In addition, the detailed description of the beam conversion apparatus of the present invention will be described later in FIG. 1B and the following drawings, and the detailed description thereof will be omitted. 1A illustrates one surface of the display device (in this embodiment, the X-axis direction surface).

Referring to FIG. 1A, the display apparatus includes the beam conversion apparatus (see identification code A of FIG. 1A) of the present invention, and as other components, the light source 100, the light modulator 140, the reflection mirror 150, It further includes a projection lens 160, the scanner 170. In this case, the two-dimensional beam irradiated from the light source 100 is converted into a one-dimensional beam while passing through the first lens 110, the second lens 120 and the beam conversion lens 130 of the beam conversion apparatus of the present invention and incident light The light is incident on the optical modulator 140 to perform modulation. The incident one-dimensional beam is modulated by diffracted light while passing through the optical modulator 140, and is then projected onto the screen 180 via the reflective mirror 150, the projection lens 160, the scanner 170, and the like. Here, the reflective mirror 150 changes the optical path of the diffracted light emitted from the light modulator 140 and assists the light to be transmitted to the screen 180 by a shorter path, and the projection lens 160 serves to diffract light. Serves to enlarge the projection. However, the reflective mirror 150 and the projection lens 160 may be omitted in some cases.

1B is a view showing one side and the other side of the beam conversion apparatus according to an embodiment of the present invention. Here, FIG. 1B (a) illustrates a case where the beam conversion apparatus according to the exemplary embodiment of the present invention is viewed from one surface (for example, the first axis direction, for example, the Y axis direction), and FIG. 1B (b). Is a view of the beam conversion apparatus according to an embodiment of the present invention seen from the other surface (second axis direction, for example, X axis direction), and FIGS. 1B (c) to (f) illustrate the present invention. Illustrates the shape of the beam that changes as it passes through each component of the beam conversion apparatus according to an embodiment.

Referring to (a) and (b) of FIG. 1B, a beam conversion apparatus according to an embodiment of the present invention may include a first lens 110 having a first refractive surface 115 and a first lens having a second refractive surface 125. Two lenses 120 and a beam conversion lens 130.

The first lens 110 receives an input (incident) of a two-dimensional beam (assuming a shape as shown in FIG. 1B (c)) emitted from the light source 100 (see (d) of FIG. 1B). In this case, the input two-dimensional beam is enlarged (diffused) in the first axis direction while passing through the first refractive surface 115 formed on the first lens 110 (see (e) of FIG. 1B). That is, the first refracting surface 115 expands and deflects the input two-dimensional beam in the first axis direction so that the length of the input two-dimensional beam in the first axis direction can be enlarged. In order to enlarge the two-dimensional beam in the first axis direction, a concave lens may be used as the first lens 110, and the first refractive surface 115 formed on the first lens 110 may be formed of the two-dimensional beam. It may be manufactured to have a negative refractive index corresponding to the uniaxial direction. The reason for enlarging the diameter (area) of the input two-dimensional beam using the first refraction surface 115 is that the two-dimensional beam irradiated from the light source 100 (for example, a laser device) has a small diameter, This is because it is necessary to enlarge the diameter of the two-dimensional beam in the display device to be implemented.

Here, a lens or refractive surface having a negative refractive index means that the diameter (or area) of the beam is enlarged when the beam passes through this lens or refractive surface, and having a positive refractive index means that the beam has a lens or refractive surface. If it passes, it means that the diameter of the beam is reduced. In addition, in all the following drawings including FIG. 1B, it is assumed that the first axis direction of the two-dimensional beam indicates the Y-axis direction and the second axis direction indicates the X-axis direction, but it may be reversed. In addition, in all the following drawings including FIG. 1B, it is assumed that the two-dimensional beam irradiated from the light source 100 is directly input to the first lens 110, but the two-dimensional beam irradiated from the light source 100 may be described. Of course, it may be input to the first lens 110 via another component. For example, the 2D beam irradiated from the light source 100 may be collimated through a collimation lens (not shown) and then input to the first lens 110. In addition, in all of the following drawings including FIG. 1B, the two-dimensional beam irradiated from the light source 110 passes through the first refractive surface 115 of the first lens 110 only in one direction (first axial direction). Although it is assumed that it is enlarged, the enlargement is performed in all directions (ie, both the first axis direction and the second axis direction) of the two-dimensional beam according to the shape (shape) of the refractive surface formed on the first lens 110. It may be obvious.

In this case, the first refractive surface 115 may be manufactured as an aspheric profile. As described above, when the first refraction surface 115 is manufactured aspheric, the error of spherical aberration and the like can be reduced as compared with the case of producing aspherical surface, and the diameter (or area) of the two-dimensional beam is enlarged so that the second lens 120 Alternatively, the transmission loss of the beam may also be reduced in the process of being transmitted to the beam conversion lens 130, thereby increasing the illuminance uniformity of the beam input to the optical modulator 140 to be described later (that is, maintaining a constant light intensity distribution). There is an advantage to that.

The second lens 120 receives a two-dimensional beam whose length in the first axial direction is enlarged through the first refractive surface 115 of the first lens 110. In this case, the two-dimensional beam input to the second lens 120 passes through the second refracting surface 125 formed on the second lens 120 and the divergence angle is adjusted to emit in parallel. That is, the second refracting surface 125 reduces the divergence angle of the two-dimensional beam emitted in the first axial direction while passing through the first refracting surface 115 of the first lens 110 so as to be output in parallel. In order to reduce the divergence angle of the input two-dimensional beam, a convex lens may be used as the second lens 120, and the second refracting surface 125 may have a positive value corresponding to the first axial direction of the input two-dimensional beam. It can be manufactured to have a refractive index. In all of the following drawings including FIG. 1, the two-dimensional beam, which is enlarged (emitted) through the first refractive surface 115 of the first lens 110, is again passed through the second refractive surface 125 of the second lens 120. Although a case of parallel emission is assumed, the second lens 120 having the second refractive surface 125 is not necessarily provided in the beam conversion apparatus of the present invention. For example, the two-dimensional beam enlarged through the first refractive surface 115 may be directly input to the beam conversion lens 130 of the present invention. However, in all the drawings below, it is assumed that the divergence angle is adjusted so that the two-dimensional beam after passing through the second refractive surface 125 is emitted in parallel as shown in FIG. 1B.

The beam conversion lens 130 receives a two-dimensional beam that is output in parallel through the second refractive surface 125 of the second lens 120. As described above, when the second lens 120 having the second refractive surface 125 is omitted in the beam conversion apparatus of the present invention, the first axial direction passes through the first refractive surface 115 of the first lens 110. Of course, a two-dimensional beam having an enlarged length may be directly input to the beam conversion lens 130. Here, the beam conversion lens 130 is input by condensing the length of a second axial direction (the second axial direction is orthogonal to the first axial direction, and the like) of the input two-dimensional beam to one focal point at a predetermined distance. The two-dimensional beam is converted into a one-dimensional beam (see (b) and (f) of FIG. 1B). That is, the input two-dimensional beam is converted into a one-dimensional beam while passing through the beam conversion lens 130, and the line incident (that is, one-dimensional incidence) to the light modulator 140. Here, the one-dimensional incidence column defined in the present specification means that the width of one of the beams incident to the optical modulator 140 in the second axial direction (see identification code l in FIG. 1B) is the optical modulator 140. It means a case where the value is equal to or smaller than the size of 1 pixel (fixel) of. For example, assuming that the size of one pixel of the optical modulator 140 is about 20 μm in the horizontal direction and the vertical direction, respectively, in any one axial direction of the beam incident on the optical modulator 140 (in this embodiment example). The case may correspond to the case where the width of the second axis direction) is within 20 μm. In the present exemplary embodiment, the beam passing through the beam conversion lens 130 is described as a one-dimensional incident object with respect to the optical modulator 140 (hereinafter, as described above). However, the object to which the one-dimensional beam is incident is necessarily an optical modulator ( It is obvious that the present invention is not limited to 140).

As described above, in order to cause the two-dimensional beam passing through the beam conversion lens 130 to enter the optical modulator 140 in one dimension, the focal point in the second axis direction of the beam conversion lens 130 (for example, the X axis direction). The distance may be set to match the separation distance between the beam conversion lens 130 and the light modulator 140. In this case, the beam conversion lens 130 may be set to maintain the length in the first axis direction of the input two-dimensional beam. To this end, the beam conversion lens 130 may be manufactured such that the curvature exists only in one direction surface, and the one direction surface in which the curvature exists in the beam conversion lens 130 may be the second axis direction of the input two-dimensional beam. It may be a surface corresponding to the same direction (see identification number 135 in (b) of Figure 1b). A cylinder lens or the like may be used as the beam conversion lens 130. As described above, any one direction surface in which curvature exists is converted into a 1D beam of an input 2D beam (condensing). It can be manufactured to have a positive refractive index for.

FIG. 2 is a diagram illustrating a table showing magnification characteristics when an input two-dimensional beam is enlarged in a first axis direction through a first refractive surface of the present invention.

2A illustrates a diameter of a two-dimensional beam irradiated from the light source 100 and input to the first refractive surface 115, and FIG. 2B illustrates a radius of curvature of the first refractive surface. 2 (c) shows a conic factor of the two-dimensional beam enlarged in the first axis direction through the first refracting surface 115, and FIG. 2 (d) shows the input two-dimensional beam. The magnification when enlarged in the first axial direction via the first refracting surface 115 is shown.

Referring to the table of FIG. 2, the diameter of the input two-dimensional beam (see FIG. 2A) is determined by a predetermined magnification (see FIG. 2D) while passing through the first refractive surface 115. It is expanding in one axis direction. In this case, when the diameter of the input two-dimensional beam is multiplied by the magnification of the first refractive surface 115, the two-dimensional beam after passing through the first refractive surface 115 regardless of the combination of various values illustrated in the table may be used. It can be seen that the length of the first axis direction is constant to 8mm. As such, in order to maintain the length of the two-dimensional beam extending in the first axial direction after passing through the first refractive surface 115, the radius of curvature and the cone coefficient of the first refractive surface 115 are illustrated in FIGS. 2B and 2B. It may be composed of a combination of various values as illustrated through (c) of FIG. That is, when the radius of curvature and the cone coefficient of the first refracting surface 115 are set as shown in FIGS. 2B and 2C, an enlarged magnification as shown in FIG. 2D can be realized.

3A and 3B are graphs showing an increase in illuminance uniformity of a beam when it passes through the beam conversion apparatus of the present invention. 3A is a graph illustrating illuminance uniformity of beams incident on the light modulator 140 when the beam converting apparatus of the present invention is not passed, and FIG. 3B is a light modulator 140 when passing through the beam converting apparatus of the present invention. Fig. 1 is a graph illustrating illuminance uniformity of the beam incident on the? 3A and 3B, the X axis of the graph represents a distance when the center of the first axis direction of the light changer 140 is referred to, and the Y axis of the graph represents relative illuminance.

Referring to FIG. 3A, when the illuminance at the center of the first axis direction of the optical modulator 140 is assumed to be 1, the relative illuminance rapidly decreases away from the center thereof, and the first axis of the optical modulator 140 is reduced. The relative illuminance value decreases to about 0.2 when reaching a point of ± 0.8 mm from the center of the direction. That is, in general, the relative illuminance of the beam irradiated from the light source 100 has a form of Gaussian distribution as shown in FIG. 3A, and in this case, the illuminance uniformity of the beam incident on the light modulator 140 (that is, the light intensity distribution). Uniformity) is not very good.

Referring to FIG. 3B, it can be seen that the relative illuminance from the center of the first axial direction of the optical modulator 150 to a point of about ± 4 mm has a value close to one. As a result, even when the length of the first axial direction of the optical modulator 140 is about ± 4 mm from its center, the light intensity of the beam incident to the optical modulator 140 through the beam conversion device of the present invention is constant. It means you can keep it. As such, when the light intensity of the beam incident on the light modulator 140 is kept constant, light modulation through the light modulator 140 may be more accurately performed, and an image may be realized in an optical device and a display device manufactured using the light modulator 140. There is an advantage to increase the accuracy of. The reason why the light intensity of the beam can be maintained in the case of passing through the beam conversion apparatus of the present invention is to minimize light loss through the first refractive surface 115, the beam conversion lens 130, and the like as described above with reference to FIG. 1. This is of course because it can maximize the light collection efficiency.

FIG. 4A is a diagram illustrating one surface of a beam conversion apparatus according to an embodiment of the present invention illustrated in FIG. 1B, and FIG. 4B is a diagram illustrating actual implementation data of the beam conversion apparatus illustrated in FIG. 4A.

Here, one surface of the beam conversion apparatus of the present invention illustrated in FIG. 4A represents a direction surface corresponding to the first axis direction of the two-dimensional beam, and it is assumed that the first axis direction means the Y axis direction. In addition, each parameter in the table illustrated in FIG. 4B will be described below. 'Y Radius' in the table is data representing the radius of curvature in the first axis direction with respect to each part in the beam conversion apparatus of the present invention, and 'Thickness' is the distance with respect to each part in the beam conversion apparatus of the present invention. 'Glass' is the data representing the glass properties of each part in the beam conversion apparatus of the present invention, and 'Diameter' is the change of the input two-dimensional beam as it passes through each part of the beam conversion apparatus of the present invention. Data indicating the diameter of the beam is 'Conic' is the data indicating the cone coefficient when the input two-dimensional beam is enlarged through the first refractive surface 115 of the present invention. 5A, 5B, 6A, and 6B to be described below, the same description as above.

Referring to FIGS. 4A and 4B, actual implementation data for implementing a beam conversion apparatus according to an embodiment of the present invention will be described based on the distance between each part and the radius of curvature of each part. First, in the case of the distance between the parts of the beam conversion apparatus of the present invention, the distance d1 between the light source 100 and the incident surface of the first lens 110 is 10 mm, and the incident surface of the first lens 110 The distance d2 between the first refractive surface 115 of the first lens 110 is 1 mm, the distance d3 between the first refractive surface 115 and the incident surface of the second lens 120 is 15.28 mm, and the second The distance d4 between the incident surface of the lens 120 and the second refractive surface 125 of the second lens 120 may be set to 2 mm. Subsequently, the distance d5 between the second refractive surface 125 and the incident surface of the beam conversion lens 130 is 0.2 mm, the distance d6 between the incident surface and the exit surface of the beam conversion lens 130 is 1.5 mm, and the beam The distance d7 between the emission surface of the conversion lens 130 and the light modulator 140 may be set to 15 mm. In addition, in the case of the radius of curvature of the respective portions in the beam conversion apparatus of the present invention, the radius of curvature r3 of the first refractive surface 115 of the first lens 110 is 1, and the second of the second lens 120 is the second. The radius of curvature r5 of the refracting surface 125 may be set to −13.363. The radius of curvature of the other portions is set to infinity (ie, the radius of curvature is infinity), where the radius of curvature means that the portion is flat without curvature. In this case, referring to the 'diameter' of the table of FIG. 4B, the 2D beam input to the beam converting apparatus of the present invention by the distance, curvature radius, etc. set as described above is the first refractive surface 115 of the first lens 110. It can be seen that the length of the first axis direction (for example, in the case of the Y-axis in the case of the table of FIG. 4B) is expanded from 3 mm to 10 mm and is incident on the optical modulator 140 while passing through.

FIG. 5A is a view showing one surface of a beam conversion apparatus according to another embodiment of the present invention, FIG. 5B is a view illustrating actual implementation data of the beam conversion apparatus shown in FIG. 5A, and FIG. 6A is still another embodiment of the present invention. FIG. 6B is a diagram illustrating one surface of a beam conversion apparatus according to an embodiment, and FIG. 6B is a diagram illustrating actual implementation data of the beam conversion apparatus illustrated in FIG. 6A.

Referring to FIG. 5A, in the beam converting apparatus according to another embodiment of the present invention, the position of the first refracting surface 115 of the first lens 110 may correspond to that of the first refracting surface 115 of the beam converting apparatus of FIG. 4A. It is produced differently from the position. That is, in the beam conversion apparatus according to the exemplary embodiment of FIG. 4A, the first refractive surface 115 is positioned at the exit surface of the first lens 110, but according to another exemplary embodiment of the present invention of FIG. 5A. In the case of the beam conversion apparatus, the first refractive surface 115 is positioned on the incident surface of the first lens 110. Accordingly, the actual implementation data for the fabrication of the beam conversion apparatus of FIG. 5A is the same as the table illustrated in FIG. 5B, which can be easily understood by the contents of the foregoing detailed description of the table of FIG. 4B. Detailed description of the actual implementation data is omitted.

Referring to FIG. 6A, in the beam converting apparatus according to another embodiment of the present invention, the positions of the second lens 120 and the beam converting lens 130 are different from the respective positions in the beam converting apparatus of FIG. 5A. It is produced. That is, in the beam conversion apparatus according to another embodiment of the present invention of FIG. 5A, the second lens 120 is disposed on the front surface of the beam conversion lens 130, but according to another embodiment of the present invention of FIG. 6A. In the beam conversion apparatus according to the related art, the second lens 120 is disposed on the rear surface of the beam conversion lens 130. Accordingly, the actual implementation data for manufacturing the beam conversion apparatus of FIG. 6A is the same as the table illustrated in FIG. 6B, and a detailed description thereof will be omitted. However, the beam conversion apparatus of the present invention is not limited to the configuration, configuration, and implementation data illustrated through FIGS. 4A to 6B, and it is apparent that various configuration, configuration, and implementation data may exist.

As described above, the present invention may be implemented by the first lens 110 (one aspherical lens) and the other two lenses (the second lens 120 and the beam conversion lens 130, for example, two spherical cylinder lenses). It is possible to manufacture a beam conversion device having excellent condensing efficiency and illuminance uniformity with a simple configuration, and the size of the fabricated beam conversion device is only a few tens of mm units (see the table of FIGS. 4B, 5B, and 6B). Therefore, there is an advantage that can be applied to a large display device as well as a small display device, an optical device, a lighting device.

7A and 7B are views illustrating a structure of an optical modulator, which is one of incident objects of a 1D beam converted through the beam conversion apparatus of the present invention. 7A is a perspective view showing one embodiment of a piezoelectric light modulator element applicable to the present invention, and FIG. 7B is a perspective view showing another embodiment of a piezoelectric light modulator element applicable to the present invention.

Here, the optical modulator is largely divided into a direct method of directly controlling the on / off of light and an indirect method using reflection and diffraction, and the indirect method is again divided into electrostatic methods (for example, GLV (Grating Light of Silicon Light Machine Co., Ltd.). Valve) device, etc.) and piezoelectric method. Such an optical modulator is applicable to the present invention irrespective of the above driving method, but the optical modulation principle will be described below with reference to the optical modulator elements shown in FIGS. 7A and 7B.

7A and 7B, a piezoelectric optical modulator device applicable to the present invention includes a substrate 51, an insulating layer 52, a sacrificial layer 53, a structure layer 54, and a piezoelectric driver 55. It includes. Here, the sacrificial layer 53 is positioned at both side ends of the insulating layer 52 so as to allow the insulating layer 52 and the structure layer 54 to be spaced apart by a predetermined interval. However, when the substrate 51 itself is embodied in a recessed form, the sacrificial layer 53 may be omitted. The piezoelectric driver 55 contracts or expands according to the voltage difference between the upper electrode and the lower electrode to provide a driving force to move the center portion of the structure layer 54 up and down.

Here, a plurality of holes 54 (b) or 54 (d) may be provided in the central portion of the structure layer 54, and on the central portion of the structure layer 54 where the holes are not formed. An upper light reflection layer 54 (a) or 54 (c) that reflects or diffracts incident light is a lower light reflection layer 52 (a) or 52 that reflects or diffracts incident light on the insulating layer 52 corresponding to the position of the hole. (b)) may be formed. Hereinafter, the light modulation principle according to the height change between the structure layer 54 and the insulating layer 52 will be described with reference to FIGS. 7C and 7D.

7C and 7D are diagrams for describing a light modulation principle in the light modulator of FIG. 7A. Here, FIG. 7C is a plan view of an optical modulator composed of the array of optical modulator elements of FIG. 7A, and FIG. 7D is a cross-sectional view taken along line BB 'of FIG.

Referring to FIG. 7C, the optical modulator includes a first pixel (pixel # 1), a second pixel (pixel # 2),. And m micromirrors 50-1, 50-2,..., 50-m that are responsible for the m-th pixel (pixel #m). The optical modulator is responsible for the image information for the one-dimensional image of the vertical scanning line or the horizontal scanning line (assuming that the vertical scanning line or the horizontal scanning line is composed of m pixels), and each micromirror 50-1, 50- 2, ..., 50-m) are in charge of any one of m pixels constituting the vertical scanning line or the horizontal scanning line.

Thus, the reflected and diffracted light in each micro mirror is then projected by the scanner into a two dimensional image on the screen. For example, for VGA 640 * 480 resolution, 640 modulations are made on one side of the scanner for 480 vertical pixels, creating one frame of screen per side of the scanner.

Hereinafter, the principle of light modulation will be described based on the first pixel (pixel # 1). However, the same content can be applied to other pixels.

In this embodiment, it is assumed that there are two holes 54 (b) -1 formed in the structure layer 54. Due to the two holes 54 (b)-1, three upper light reflection layers 54 (a)-1 are formed on the structure layer 54. In the insulating layer 52, two lower light reflection layers are formed corresponding to the two holes 54 (b)-1. In addition, another lower light reflection layer is formed on the insulating layer 52 corresponding to the portion of the gap between the first pixel (pixel # 1) and the second pixel (pixel # 2). Therefore, the number of the upper light reflecting layers 54 (a) -1 and the lower light reflecting layers per pixel becomes the same, and it is possible to adjust the luminance of the modulated light by using zero-order diffraction light or ± first-order diffraction light.

Referring to FIG. 7D, when the wavelength of light is λ, the distance between the structure layer 54 on which the upper light reflection layer 54 (a) is formed and the insulating layer 52 on which the lower light reflection layer 52 (a) is formed ( The first voltage to make 2n) λ / 4 (n is a natural number) is applied to the piezoelectric drive member 55 (see (a) of FIG. 4D). In this case, in the case of zero-order diffracted light (reflected light), the light reflected from the upper light reflecting layer 54 (a) formed on the structure layer 54 and the lower light reflecting layer 52 (a) formed on the insulating layer 52 The total path difference between the light reflected from the () is equal to nλ so that constructive interference causes the diffracted light to have maximum luminance. Here, in the case of + 1st and -1st diffraction light, the brightness of light has a minimum value due to destructive interference.

Further, the distance between the structure layer 54 on which the upper light reflection layer 54 (a) is formed and the insulating layer 52 on which the lower reflection layer 52 (a) is formed is (2n + 1) λ / 4 (n is a natural number). A second voltage is applied to the piezoelectric driver 55 so as to be (see FIG. 4D (b)). In this case, in the case of zero-order diffracted light (reflected light), the light reflected from the upper light reflecting layer 54 (a) formed on the structure layer 54 and the lower light reflecting layer 52 (a) formed on the insulating layer 52. The total path difference between the light reflected from the light beam is equal to (2n + 1) λ / 2 so that the destructive light has the minimum luminance. In the case of the + 1st and -1st diffracted light, the luminance of light has a maximum value due to constructive interference. As a result of the above-described interference, the optical modulator can adjust the amount of reflected or diffracted light so that image information can be loaded onto the light. This principle is a light modulation process of incident light.

In the above, the case in which the distance between the structure layer 54 and the insulating layer 52 is (2n) λ / 4 or (2n + 1) λ / 4 has been described. However, the intensity of interference caused by diffraction or reflection of incident light can be adjusted. Obviously, various embodiments that can be driven at intervals of time can be applied to the present invention.

As described above, according to the beam converting apparatus according to the present invention, in converting (condensing) a two-dimensional beam irradiated from a light source into a one-dimensional beam, the condensing efficiency of the converted one-dimensional beam is further maximized, There is an effect to improve the sex.

In addition, the present invention has an effect that can be applied to small digital devices such as mobile phones and PMPs as well as large display devices by simplifying the configuration of the optical device (or lighting device) and reducing the volume of the manufactured optical device.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art to which the present invention pertains without departing from the spirit and scope of the present invention as set forth in the claims below It will be readily understood that modifications and variations are possible.

Claims (7)

A first lens refracting the input two-dimensional beam so that the length in the first axial direction of the input two-dimensional beam can be enlarged; The 2D beam is condensed by focusing a length in a second axis direction orthogonal to the first axis direction of the 2D beam in which the length in the first axis direction is enlarged through the first lens to one focal point at a predetermined distance. A beam conversion lens for converting to a dimensional beam; And A second lens positioned at the front or rear of the beam conversion lens and configured to adjust a divergence angle of a two-dimensional beam having a length in the first axial direction enlarged through the first lens; Beam conversion apparatus comprising a. The method of claim 1, And the refractive surface in the first axial direction of the first lens is an aspheric profile. The method of claim 1, And the beam conversion lens maintains the length in the first axial direction of the two-dimensional beam in which the length in the first axial direction is enlarged through the first lens. The method of claim 3, The beam conversion lens is present in only one direction of curvature, And the one direction surface in which the curvature exists in the beam conversion lens is a surface corresponding to the same direction as the second axis direction of the two-dimensional beam. The method of claim 1, And the beam conversion lens is a cylinder lens. The method of claim 1, And the second lens adjusts the divergence angle such that a two-dimensional beam having an enlarged length in the first axial direction is emitted through the first lens in parallel. The method of claim 1, One focal point at the predetermined distance from the beam conversion lens is on an optical modulator that modulates the incident beam, and the one-dimensional beam converted by the beam conversion lens is transferred to the optical modulator, The optical modulator, Board; An insulating layer on the substrate; A lower light reflection layer disposed on the insulating layer and reflecting or diffracting incident light; A structure layer having a central portion spaced apart from the insulating layer by a predetermined distance; An upper light reflection layer positioned on the central portion of the structure layer and reflecting or diffracting incident light; And And a piezoelectric driver positioned on the structure layer and moving the central portion of the structure layer up and down.

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