TW202345480A - Method for improving organic semiconductor laser device, program, computer and organic semiconductor laser device - Google Patents

Abstract

An organic semiconductor laser device with a supercell structure composed of a first short-pitch periodic structure with length WS1, a long-pitch periodic structure with length WL and a second short-pitch periodic structure with length WS2 is improved by lengthening (WS1 + WS2), shortening WL, lengthening (WS1 + WL + WS2), or repeating the supercell structure.

Description

Method, program, computer and organic semiconductor laser device for improving organic semiconductor laser device

The present invention relates to a method for improving an organic semiconductor laser device.

In previous sensing technologies such as 2D and 3D imaging (e.g., biometric measurement and identification) that project a known light pattern called "structured light" onto an object, diffractive optical elements (DOE) are used The laser light source. DOE is specifically designed to separate a single laser beam into multiple spot beams to cover a large field of view, linear or other geometric shapes of light. DOE is a large volume element composed of lenses and waveguides. Therefore, using DOE will limit the miniaturization and volume density of such optical sensing systems and increase costs. Therefore, there is a need to develop a laser device that can separate laser beams without using DOE. On the other hand, in recent years, an organic semiconductor has been developed that has great potential as a gain medium. Organic semiconductor lasers (OSLs) are excellent devices because they provide wide optical gain and fine wavelength tuning through a wide range of molecular designs from blue to near-infrared regions with relatively low laser thresholds. ^1-3 However, existing injection lasers such as organic semiconductor laser diodes (OSLD) are still in a very early stage, and therefore require extensive development from both materials and device structures. One of the key issues in organic devices is film thickness limitation. To achieve efficient carrier injection and transport in organic layers, thin film structures of several hundred nanometers are required. Therefore, it is necessary to design an optimal optical resonator structure suitable for thin film OSLD. Optical resonators play a major role in improving the performance of organic layers because they can confine, amplify and output coupling light. For example, there are several resonators including Fabry-Perreault interferometer ⁴ , distributed Bragg reflector (DBR), including vertical cavity surface emitting laser (VCSEL) ⁵ and distributed feedback (DFB) ⁶ structures. Among such resonators, DFB resonators are strong candidates for organic layers. ^7-9 First-order DFB resonators have been used in traditional inorganic semiconductor lasers to achieve planar directivity feedback and laser emission. ¹⁰ In addition, second-order DFB resonators are also good candidates due to their surface emission. In addition, hybrid-order DFB resonators that combine first-order and second-order resonators have also been reported. Since hybrid-order DFB resonators combine the advantages of first-order (strong transverse feedback) and second-order DFB resonators (extracting part of the light as surface emission), surface-emitting lasers can be realized with low thresholds. ¹¹ Although this DFB structure provides a relatively low laser threshold, there are key issues in the control of emission angle distribution. For example, face recognition and time-of-flight (ToF) technology require many high-density laser beam points so that the sensor can detect geometric shapes and reconstruct 3D space with high resolution (Non-Patent Document 1). ¹² However, this angular gap limits its application because the limited amount of light beam reflected onto the object deteriorates the sensing resolution. Again, this is extremely important for a variety of display applications. At the same time, the existing density threshold must be significantly reduced through appropriate DFB structural design, because organic gain materials are usually fragile under high-power optical and electrical excitation. In particular, for electrically driven OSLD, various annihilation processes such as singlet-triplet annihilation (STA) and triplet-triplet annihilation (TTA) are inevitable. This is because the electric pump based on the recognized spin statistics A large number of triplet states are generated, that is, a singlet state and a triplet state with a formation ratio of 1:3 are generated. The long-lived triplet state will cause strong quenching of the radioactive singlet state (Non-patent Document 2). ¹³ Therefore, it is highly desirable to lower the threshold by optimizing the DFB structure to suppress these annihilations. non-patent literature

[Non-patent document 1] S. Zhou, and S. Xiao, HCIS 8, 1-27 (2018) [Non-patent document 2] C. Gårtner, C. Karnutsch, U. Lemmer, and C. Pflumm, J. Appl. Phys. 101, 023107 (2007)

In view of this situation, the present inventors have conducted in-depth research with the aim of providing an organic semiconductor laser device exhibiting a low laser threshold. The inventors of the present invention have conducted further in-depth research, with the aim of providing an organic laser device capable of emitting a separated laser beam without using an additional optical system such as a DOE. As a result of in-depth research to achieve the purpose, the present inventors found that by arranging two or more supercrystals having first and second short-pitch periodic structures and a long-pitch periodic structure in an optical resonator structure, Cell structure, and controlling the length of each periodic structure in the direction orthogonal to the lattice groove can reduce the laser threshold. In addition, the present inventors also found that by controlling the length of the periodic structure in the direction orthogonal to the lattice grooves, it is possible to achieve split laser beams with a narrow angle difference between the diffraction angles. The present invention is proposed in view of the relevant knowledge and is implemented by the following configuration.

[1] A method for improving an organic semiconductor laser device including an optical resonator structure and a light amplification layer composed of an organic semiconductor, wherein The above-mentioned optical resonator structure has at least one supercell structure, and the above-mentioned supercell structure has a first short-pitch periodic structure, a long-pitch periodic structure and a second short-pitch periodic structure, The first short-pitch periodic structure is disposed adjacent to one end of the long-pitch periodic structure, and the second short-pitch periodic structure is disposed adjacent to the other end of the long-pitch periodic structure, (i) the direction orthogonal to the lattice grooves of the above-mentioned first short-pitch periodic structure, (ii) the direction orthogonal to the lattice grooves of the above-mentioned long-pitch periodic structure, and (iii) the above-mentioned second short section On a straight line from at least two of the directions orthogonal to the lattice grooves of the periodic structure, The above method includes at least one of the following: (1) Extended (WS1+WS2), (2) Shorten WL, (3) Extended (WS1+WL+WS2) and (4) Repeat the above supercell structure, WS1 represents the length of the first short-pitch periodic structure in the direction orthogonal to the lattice grooves, and WS2 represents the length of the second short-pitch periodic structure in the direction orthogonal to the lattice grooves. , WL represents the length in the direction orthogonal to the lattice groove of the above-mentioned long-pitch periodic structure. [2] The method described in [1], implementing (1). [3] The method described in [1], and its implementation (2). [4] The method described in [1], and its implementation (3). [5] The method described in [1], and its implementation (4). [6] The method described in [1], which implements (1) and (2). [7] The method described in [1], which implements (1) and (3). [8] The method described in [1], which implements (2) and (3). [9] The method described in [1], which implements (1), (2) and (3). [10] The method according to any one of [6] to [9], further implementing (4). [11] The method according to any one of [1] to [10], which adjusts (WS1+WS2)/WL to 4 or more, for example, 10 or more, 50 or more, 90 or more, 150 or more, or 800 or more . [12] The method according to any one of [1] to [11], which adjusts (WS1 + WS2) to 1 μm or more, for example, 4 μm or more, 10 μm or more, 40 μm or more, or 200 μm or more. [13] The method according to any one of [1] to [12], which adjusts WL to 10 μm or less, for example, 2 μm or less, or 0.6 μm or less. [14] The method according to any one of [1] to [13], which adjusts (WS1+WL+WS2) to 2 μm or more, for example, 5 μm or more, 20 μm or more, 50 μm or more, or 250 μm or more. [15] The method described in any one of [1] to [14], which satisfies WS1=WS2. [16] The method according to any one of [1] to [15], wherein (i) the direction orthogonal to the lattice grooves of the above-mentioned first short-pitch periodic structure, (ii) the direction orthogonal to the lattice grooves of the above-mentioned long-pitch periodic structure, and (iii) the above-mentioned second short section The directions orthogonal to the lattice grooves of the periodic structure are all on a straight line. [17] The method according to any one of [1] to [16], wherein The first short-pitch periodic structure is in contact with one end of the long-pitch periodic structure, and the second short-pitch periodic structure is in contact with the other end of the long-pitch periodic structure. [18] The method according to any one of [1] to [17], wherein The periodic structure includes a grating composed of ridges and grooves. [19] The method as described in any one of [1] to [18], wherein The first short-pitch periodic structure and the second short-pitch periodic structure are first-order gratings, and the long-pitch periodic structure is a second-order grating. [20] The method according to any one of [1] to [19], wherein The above method is used to reduce the laser threshold. [21] The method according to any one of [1] to [19], wherein The above method is used to narrow the diffraction angle of laser emission. [22] The method as described in any one of [1] to [19], wherein The above method is used to reduce the laser threshold and narrow the diffraction angle of laser emission. [23] The method according to any one of [1] to [22], wherein The above method is used to design organic semiconductor laser devices. [24] The method according to any one of [1] to [23], wherein The above method is used to evaluate organic semiconductor laser devices. [25] The method according to any one of [1] to [24], wherein The above method is used to manufacture organic semiconductor laser devices. [26] A program for implementing the method described in any one of [1] to [25]. [27] A computer for implementing the method described in any one of [1] to [25]. [28] An organic semiconductor laser device manufactured by the method described in [1] to [25]. [29] An organic semiconductor laser device, which includes an optical resonator structure and a light amplification layer composed of an organic semiconductor, wherein, The above-mentioned optical resonator structure has at least one supercell structure, and the above-mentioned supercell structure has a first short-pitch periodic structure, a long-pitch periodic structure and a second short-pitch periodic structure, The first short-pitch periodic structure is disposed adjacent to one end of the long-pitch periodic structure, and the second short-pitch periodic structure is disposed adjacent to the other end of the long-pitch periodic structure, (i) the direction orthogonal to the lattice grooves of the above-mentioned first short-pitch periodic structure, (ii) the direction orthogonal to the lattice grooves of the above-mentioned long-pitch periodic structure, and (iii) the direction orthogonal to the above-mentioned second short-pitch periodic structure. At least two of the directions orthogonal to the lattice grooves of the pitch periodic structure are on a straight line, The above-mentioned organic semiconductor laser device has at least one of (WS1+WS2), shortened WL, elongated (WS1+WL+WS2) and two or more supercell structures, wherein WS1 represents the first short pitch The length of the periodic structure in the direction orthogonal to the lattice grooves, WS2 represents the length of the second short-pitch periodic structure in the direction orthogonal to the lattice grooves, and WL represents the length of the above-mentioned long-pitch periodic structure. The length of the structure in the direction orthogonal to the lattice grooves. [30] The organic semiconductor laser device as described in [28] or [29], wherein The above-mentioned optical resonator structure has two or more supercell structures arranged in such a way that directions orthogonal to the lattice grooves of the two or more supercell structures are aligned in a straight line. [31] The organic semiconductor laser device as described in [30], wherein WS1, WL and WS2 of the above two or more supercell structures are the same. [32] The organic semiconductor laser device as described in [30], wherein The lengths of the above two or more supercell structures in the direction orthogonal to the lattice grooves are random. [33] The organic semiconductor laser device according to any one of [30] to [32], wherein The above-mentioned optical resonator structure has more than 10 supercell structures. [34] The organic semiconductor laser device according to any one of [28] to [33], wherein The above-mentioned first short-pitch periodic structure, the above-mentioned long-pitch periodic structure and the above-mentioned second short-pitch periodic structure have grooves with a depth less than 75 nm, for example, 20-70 nm. [35] The organic semiconductor laser device according to any one of [28] to [34], wherein The above-mentioned first short-pitch periodic structure, the above-mentioned long-pitch periodic structure and the above-mentioned second short-pitch periodic structure have a distributed feedback (DFB) structure. [36] The organic semiconductor laser device as described in [35], wherein Each distributed feedback (DFB) structure is selected from the group consisting of first-order DFB structures, second-order DFB structures, third-order DFB structures and higher-order DFB structures. [37] The organic semiconductor laser device according to any one of [28] to [36], wherein The above-mentioned first short-pitch periodic structure, the above-mentioned long-pitch periodic structure and the above-mentioned second short-pitch periodic structure are made of insulating materials. [38] The organic semiconductor laser device according to any one of [28] to [37], wherein The above-mentioned first short-pitch periodic structure, the above-mentioned long-pitch periodic structure and the above-mentioned second short-pitch periodic structure have periodically arranged ridges made of insulating material on the insulating substrate. [39] The organic semiconductor laser device as described in [38], wherein The ridge portion and the insulating substrate are made of different insulating materials. [40] The organic semiconductor laser device as described in [38], wherein The ridge portion is made of silicon dioxide, and the insulating substrate is made of a glass substrate. [41] The organic semiconductor laser device according to any one of [38] to [40], wherein The surface of the insulating substrate is exposed at the bottom of the groove. [42] The organic semiconductor laser device according to any one of [28] to [41], further having an organic layer on the surface of the optical resonator structure. [43] The organic semiconductor laser device according to [42], further comprising a transparent protective layer on the organic layer opposite to the optical resonator structure. [44] The organic semiconductor laser device according to [42] or [43], which emits a laser beam from the side of the organic layer opposite to the optical resonator structure. [45] The organic semiconductor laser device according to [43], which emits a laser beam from the side of the organic layer opposite to the transparent protective layer. [46] The organic semiconductor laser device according to any one of [28] to [45], which emits two or more types of diffracted light with different diffraction angles. [47] The organic semiconductor laser device as described in [46], wherein Among the two or more types of diffracted light, the angle difference between the diffraction angles of the diffracted light with the closest emission angle is 8° or less, for example, 7° or less or 6° or less. [48] The organic semiconductor laser device according to any one of [28] to [47], wherein The above-mentioned organic layer contains an organic compound having at least one stilbene unit. [49] The organic semiconductor laser device according to any one of [28] to [48], wherein The above-mentioned organic layer contains 4,4'-bis[(N-carbazole)styryl]biphenyl (BSBCz). [50] The organic semiconductor laser device according to any one of [28] to [49], wherein The thickness of the organic layer is 80 to 350 nm, for example, 100 to 300 nm or 150 to 250 nm. [51] A device selected from the group including a biosensor, a structured light illumination device, an optical sensing device and a face recognition device, which includes the organic compound described in any one of [28] to [50] Semiconductor laser device.

Compatibility of all-organic platforms and OLED technologies, monolithic integration of different laser colors, and integration with electroluminescent devices and other organic devices will reduce the size of structured light-based sensors and optical sensor systems.

The contents of the present invention will be described in detail below. The constituent elements of the present invention will be described with reference to representative embodiments and specific examples of the present invention, but the present invention is not limited to these embodiments and examples. In this specification, the numerical range represented by “X to Y” represents a range including the numerical values X and Y as the minimum value and the maximum value, respectively.

Method for improving organic semiconductor laser device The method of the present invention is a method for improving an organic semiconductor laser device. The above-mentioned organic semiconductor laser device includes an optical resonator structure and a light amplification layer composed of an organic semiconductor, wherein The above-mentioned optical resonator structure has at least one supercell structure, and the above-mentioned supercell structure has a first short-pitch periodic structure, a long-pitch periodic structure and a second short-pitch periodic structure, The first short-pitch periodic structure is disposed adjacent to one end of the long-pitch periodic structure, and the second short-pitch periodic structure is disposed adjacent to the other end of the long-pitch periodic structure, (i) the direction orthogonal to the lattice grooves of the above-mentioned first short-pitch periodic structure, (ii) the direction orthogonal to the lattice grooves of the above-mentioned long-pitch periodic structure, and (iii) the above-mentioned second short section On a straight line from at least two of the directions orthogonal to the lattice grooves of the periodic structure, The above method includes at least one of the following: (1) Extended (WS1+WS2), (2) Shorten WL, (3) Extended (WS1+WL+WS2) and (4) Repeat the above supercell structure, WS1 represents the length of the first short-pitch periodic structure in the direction orthogonal to the lattice grooves, and WS2 represents the length of the second short-pitch periodic structure in the direction orthogonal to the lattice grooves. , WL represents the length in the direction orthogonal to the lattice grooves of the long-pitch periodic structure. The method of the invention is used to improve the performance of organic semiconductor laser devices. In one embodiment of the invention, the method is used to reduce the laser threshold. In another embodiment of the invention, the method is used to narrow the diffraction angle of the laser emission. In an embodiment of the invention, the method is used to lower the laser threshold and narrow the diffraction angle of the laser emission. The "diffraction angle of laser emission" mentioned here means the angular difference between the diffraction angles of two diffraction beams with the closest emission angles among two or more diffraction beams with different diffraction angles. The narrower the diffraction angle of the laser emission, the more the laser beam is separated and more useful as a structured illumination device for detecting 3D geometries. In the present invention, the "periodic structure" in the "first short-pitch periodic structure", "long-pitch periodic structure" and "second short-pitch periodic structure" means a plurality of lattice grooves with A structure arranged side by side at a fixed pitch. Hereinafter, the convex portions between adjacent lattice grooves are referred to as “ridge portions”. The periodic structure may be a grating in which a plurality of ridges and a plurality of grating grooves are alternately arranged at a fixed pitch. In the present invention, the "pitch" in "first short-pitch periodic structure", "long-pitch periodic structure" and "second short-pitch periodic structure" means the distance between the side surfaces of adjacent lattice grooves. distance between. In each supercell structure, the "long-pitch periodic structure" is a periodic structure with a pitch longer than that of the "first short-pitch periodic structure" and the "second short-pitch periodic structure". Regarding the description of the organic semiconductor laser device used in the present invention, reference may be made to the description in the paragraph "Organic Semiconductor Laser Device" above.

FIG. 1 shows an optical resonator structure 10 having more than three supercell structures as an example of the optical resonator structure used in the present invention. However, the optical resonator structures that can be used in the present invention should not be construed as limited to the examples. In Figure 1, "FSP" represents the first short-pitch periodic structure, "LP" represents the long-pitch periodic structure, and "SSP" represents the second short-pitch periodic structure. In the optical resonator structure 10, the distance Λ1 between the side surfaces of adjacent lattice grooves 1a and 1b corresponds to the pitch of the aforementioned first short-pitch periodic structure FSP, and the distance Λ1 between the side surfaces of adjacent lattice grooves 3a and 3b The distance ΛL between them corresponds to the pitch of the long-pitch periodic structure LP, and the distance Λ2 between the side surfaces of adjacent lattice grooves 2a and 2b corresponds to the pitch of the second short-pitch periodic structure SSP. In the optical resonator structure 10, the direction pointed by the arrow x is the direction orthogonal to the lattice groove, the length of the first short pitch structure FSP in the x direction corresponds to WS1, and the length of the long pitch structure LP in the x direction The length of corresponds to WL, and the length of the second short pitch structure in the x direction corresponds to WS2.

In each supercell structure, the first short-pitch periodic structure is arranged adjacent to one end of the long-pitch periodic structure, and the second short-pitch periodic structure is adjacent to the other end of the long-pitch periodic structure. adjacent configuration. The first short pitch periodic structure may be in contact with one end of the long pitch periodic structure, and the second short pitch periodic structure is in contact with the other end of the long pitch periodic structure, In each supercell structure, (i) the direction orthogonal to the lattice grooves of the first short-pitch periodic structure, (ii) the direction orthogonal to the lattice grooves of the long-pitch periodic structure, and ( iii) At least two of the directions orthogonal to the lattice grooves of the second short-pitch periodic structure are on a straight line. The directions on a straight line may be (i) and (ii), (i) and (iii), (ii) and (iii), (i), (ii) and (iii). (i), (ii) and (iii) can all be on a straight line.

In each supercell structure, the pitches of the first short-pitch periodic structure and the second short-pitch periodic structure may be the same as each other, or may be different from each other, for example, they may be the same. The lengths WS1 and WS2 may be the same as each other, or may be different from each other, for example, they may be the same. In an embodiment of the present invention, the pitches of the first short pitch structure and the second short pitch structure may be the same, and the first short pitch structure and the second short pitch structure satisfy W1=W2.

The method of the present invention includes at least one of the steps (1) to (4) above. The steps implemented in the method of the present invention may be part of (1) to (4), or may be all of (1) to (4). Embodiments of the method of the present invention include the following (A) to (I). (A) Includes methods for carrying out the steps of (1). (B) Includes methods for carrying out the steps of (2). (C) Includes methods for implementing the steps of (3). (D) Includes methods for implementing the steps of (4). (E) Includes methods for performing the steps of (1) and (2). (F) Includes methods for carrying out the steps of (1) and (3). (G) Includes methods for performing the steps of (2) and (3). (H) Includes methods of performing the steps of (1), (2), and (3). (I) In any embodiment of (A) to (H), the method includes further performing the step of (4).

In the method of the present invention, (WS1+WS2)/WL is adjusted to, for example, 4 or more, 10 or more, 50 or more, 90 or more, 150 or more, and 800 or more. In the method of the present invention, (WS1+WS2) is adjusted to, for example, 1 μm or more, 4 μm or more, 10 μm or more, 40 μm or more, and 200 μm or more. In the method of the present invention, WL is adjusted to, for example, 10 μm or less, 2 μm or less, or 0.6 μm or less. In the method of the present invention, (WS1+WL+WS2) is, for example, 2 μm or more, 5 μm or more, 20 μm or more, 50 μm or more, and 250 μm or more. In the method of the present invention, the number of supercell structures in the optical resonator structure is, for example, 4 or more, 6 or more, 8 or more, and 10 or more.

In the method of the present invention, the pitches of the first short-pitch periodic structure, the long-pitch periodic structure, and the second short-pitch periodic structure can be set to satisfy the Bragg condition expressed by the following formula (I) . In an embodiment of the present invention, the first short-pitch periodic structure and the second short-pitch periodic structure are first-order gratings, where m is respectively 1 in formula (I), and the long-pitch periodic structure is a second-order grating. grating, where m is in equation (I) 2.

Methods for designing, evaluating and manufacturing organic semiconductor laser devices Embodiments of the method of the present invention include a method for designing an organic semiconductor laser device, a method for evaluating an organic semiconductor laser device, and a method for manufacturing an organic semiconductor laser device. In a method for designing an organic semiconductor laser device, by implementing at least one of the above (1) to (4), it is possible to design an organic semiconductor that is expected to have a low laser threshold and a narrow diffraction angle of laser emission. Laser device. In the method for evaluating organic semiconductor laser devices, by satisfying (1′) (WS1+WS2) longer, (2′) WL shorter, (3′) (WS1+WL+WS2) longer and (4′) organic semiconductor devices with at least one of the conditions of a large number of supercell structures can be evaluated at a higher level, and a surrounding device with a low laser threshold and laser emission can be selected among two or more organic semiconductor laser devices. Organic semiconductor device with narrow emission angle. In the method for manufacturing an organic semiconductor laser device, by implementing at least one of the above (1) to (4), an organic semiconductor laser with a low laser threshold and a narrow diffraction angle of laser emission can be manufactured device. Regarding the description and conditions used in the method of the present invention, reference can be made to the description in the paragraph "Method for improving organic semiconductor laser device" above.

program The routines of the invention are routines for carrying out the methods of the invention. That is, the program of the present invention is a program for causing a computer to implement each step of the method of the present invention. For descriptions of the method of the present invention, reference may be made to the descriptions in the paragraphs "Method for Improving Organic Semiconductor Laser Device" and "Method for Designing, Evaluating, and Manufacturing Organic Semiconductor Laser Device" above. The program of the present invention can be stored in a computer-readable recording medium. Examples of recording media include magnetic recording media, optical recording media, and semiconductor memories. Specific examples of recording media include floppy disks, hard disks, optical disks, magneto-optical disks, CD-ROM (read-only memory), CD-R, DVD-ROM, magnetic tapes, non-volatile memory cards, ROM, EEPROM and silicon disks .

computer The computer of the present invention is a computer used to implement the method of the present invention. That is, the computer of the present invention is a computer including means for executing each step in the method of the present invention. For descriptions of the method of the present invention, reference may be made to the descriptions in the paragraphs "Method for Improving Organic Semiconductor Laser Device" and "Method for Designing, Evaluating, and Manufacturing Organic Semiconductor Laser Device" above. Examples of means that the computer of the present invention may have include calculation means for calculating the formulas in (1') and (3') above, calculation means for calculating values based on (1') and (3') and (2 ′) and (4′), select a screening method suitable for the organic semiconductor laser device of the above (1′) to (4′) in the device.

Organic semiconductor laser device The organic semiconductor laser device of the present invention is an organic semiconductor laser device including an optical resonator structure and a light amplification layer composed of an organic semiconductor, wherein, The above-mentioned optical resonator structure has at least one supercell structure, and the above-mentioned supercell structure has a first short-pitch periodic structure, a long-pitch periodic structure and a second short-pitch periodic structure, The first short-pitch periodic structure is disposed adjacent to one end of the long-pitch periodic structure, and the second short-pitch periodic structure is disposed adjacent to the other end of the long-pitch periodic structure, (i) the direction orthogonal to the lattice grooves of the above-mentioned first short-pitch periodic structure, (ii) the direction orthogonal to the lattice grooves of the above-mentioned long-pitch periodic structure, and (iii) the above-mentioned second short section On a straight line from at least two of the directions orthogonal to the lattice grooves of the periodic structure, The above-mentioned organic semiconductor laser device has at least one of elongated (WS1+WS2), shortened WL, elongated (WS1+WL+WS2) and two or more supercell structures, where WS1 is represented by the above-mentioned first short section The length from the periodic structure in the direction orthogonal to the lattice groove, WS2 represents the length of the second short-pitch periodic structure in the direction orthogonal to the lattice groove, WL represents the length in the above-mentioned long pitch period The length of the linear structure in the direction orthogonal to the lattice grooves. Regarding the first short-pitch periodic structure, the long-pitch periodic structure, and the second short-pitch structure, exemplary ranges (WS1+WS2), WL, (WS1+WS2)/WL, and (WS1+WL+WS2) For description, reference may be made to the description in the paragraph "Method for Improving Organic Semiconductor Laser Device" above.

The organic semiconductor laser device of the present invention may be an optically pumped organic semiconductor laser device, or may be an electrically pumped organic semiconductor laser device (organic semiconductor laser diode). The optical pump organic semiconductor laser device has an optical resonator structure and an optical amplification layer. The electrically pumped organic semiconductor laser device has an electrode pair, an optical resonator structure, and an organic layer including at least a light amplification layer. The components and layers of the electrically pumped organic semiconductor laser device will be described later. The description of the optical resonator structure and the optical amplification layer can also be applied to the optical resonator structure and the optical amplification layer of the optical pump organic semiconductor laser device.

electrode The electrically pumped organic semiconductor laser device of the present invention has an electrode pair. For light output, one electrode can be transparent. The electrode can be appropriately selected from electrode materials commonly used in the field according to its work function and the like. Electrode materials include Ag, Al, Au, Cu, ITO, etc., but are not limited thereto.

Optical resonator structure The optical resonator structure has the above-mentioned two or more supercell structures. The number of supercell structures in the optical resonator structure is, for example, 4 or more, 6 or more, 8 or more, and 10 or more. The optical resonator structure may have two or more supercell structures arranged in a straight line with directions orthogonal to the lattice grooves of the two or more supercell structures. In one embodiment of the present invention, WS1, WL, and WS2 of two or more supercell structures are the same. In an embodiment of the present invention, the lengths of two or more supercell structures in a direction orthogonal to the lattice grooves are random. An example of an optical resonator structure having a random supercell length that can be used in an embodiment of the present invention is shown in FIG. 2 . The optical resonator structure shown in Figure 2 has three supercell structures SC1, SC2, and SC3 with different lengths in the direction orthogonal to the lattice grooves. The configurations of the three supercell structures are random. Among them, the lengths of the three supercell structures are represented by the following formulas. WL ₁ =30Λ ₁ +6Λ ₂ +30Λ ₁ WL ₂ =20Λ ₁ +5Λ ₂ +20Λ ₁ WL ₃ =8Λ ₁ +3Λ ₂ +8Λ _1Among them, WL ₁ , WL ₂ and WL ₃ are three kinds of supercell structures For each length in the direction orthogonal to the lattice groove, Λ ₁ is the pitch of the first short-pitch periodic structure, and Λ ₂ is the pitch of the second short-pitch periodic structure. FIG. 3 shows the angular dependence of laser emission obtained by simulation of the far-field pattern of laser emitted from a laser device having the optical resonator structure shown in FIG. 2 . When the supercell lengths of each unit cell are different (random supercell length), the supercell will not have periodicity, which will cause the laser to only appear at a single angle of 0 degrees. The organic semiconductor laser device can be used as a laser array emitting the same wavelength at a single angle.

The first short-pitch periodic structure, the long-pitch periodic structure and the second short-pitch periodic structure of the supercell structure respectively have grooves with a depth less than 75 nm, for example, 20-70 nm. In an embodiment of the present invention, the first short-pitch periodic structure, the long-pitch periodic structure and the second short-pitch periodic structure have a distributed feedback (DFB) structure. The DFB structure is a diffraction grating structure designed to satisfy the Bragg condition of formula (I). mλ _Bragg =2n _eff Λ (I) where m is the diffraction order, λ _Bragg is the Bragg resonance wavelength, n _eff is the effective refractive index of the waveguide, and Λ is the grating period (pitch). The DFB structures of the first short-pitch periodic structure, the long-pitch periodic structure and the second short-pitch periodic structure may be selected from the group consisting of first-order DFB structures, second-order DFB structures, third-order DFB structures and higher-order DFB structures. in the group. However, in each supercell structure, the order of the DFB structure of the long-pitch periodic structure is greater than the order of the DFB structures of the first short-pitch periodic structure and the second short-pitch periodic structure.

The first short-pitch periodic structure, the long-pitch periodic structure and the second short-pitch periodic structure may be composed of insulating materials. Specific examples of insulating materials include glass, silicon dioxide and plastic. In an embodiment of the present invention, the first short-pitch periodic structure, the long-pitch periodic structure and the second short-pitch periodic structure are generally formed of insulating materials. In an embodiment of the invention, the first short-pitch periodic structure, the long-pitch periodic structure and the second short-pitch periodic structure have periodically arranged ridges made of insulating material on the insulating substrate. In this case, the ridge and the insulating substrate may be composed of different insulating materials. For example, the ridges may be composed of silicon dioxide and the insulating substrate may be composed of a glass substrate. In a periodic structure with periodically arranged ridges on an insulating substrate, the surface of the insulating substrate may be exposed at the bottom of the grooves (between adjacent ridges). The height range of the ridge may refer to the depth range of the lattice grooves mentioned above.

organic layer The organic layer at least includes a light amplification layer composed of an organic semiconductor. The organic layer can be disposed on the surface of the optical resonator structure.

Light amplifying layer in organic layer The organic semiconductor used in the light amplifying layer may be a compound composed of one or more atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms, sulfur atoms, phosphorus atoms, and boron atoms. Examples of such compounds include compounds composed of one or more atoms selected from the group consisting of carbon atoms, hydrogen atoms, and nitrogen atoms. The light amplification layer at least contains an organic semiconductor showing laser activity. The "organic semiconductor exhibiting laser activity" mentioned here means an organic semiconductor capable of inducing laser oscillation by supplying energy from the outside. Hereinafter, the "organic semiconductor exhibiting laser activity" will be referred to as a "laser active material". One example of the laser active material is a compound having at least one stilbene unit, and another example of the laser active material is a compound having at least one stilbene unit and at least one carbazole unit. The stilbene unit and the carbazole unit may be substituted by a substituent such as an alkyl group, or may be unsubstituted. The organic semiconductor compound may be a non-polymer having no repeating units. The molecular weight of the compound may be 1,000 or less, for example, 750 or less. Specific examples of laser active materials include 4,4'-bis[(N-carbazole)styryl]biphenyl (BSBCz) (the chemical structure is shown in Figure 4(d)). The light amplification layer may contain more than two types of laser active materials. For example, the light amplification layer contains only 1 laser active material. The light amplification layer may only include laser active materials, or may include other organic semiconductors other than laser active materials. Other examples of organic semiconductors are organic semiconductors as host materials. The host material used may be an organic compound with at least one of the excited singlet energy and the excited triplet energy higher than that of the laser active material. As a result, the singlet state excitation and triplet state excitation generated in the laser active material can be controlled within the molecules of the laser active material, thereby lowering the laser threshold. However, there are cases where the laser performance is improved even if the singlet excitation and the triplet excitation are not sufficiently restricted, so a host material capable of improving the laser performance can be used in the present invention without particular limitation. The host material can be suitably selected from known host materials and organic semiconductors with high glass transition temperatures. When a host material is used, the amount of the laser active material in the light amplification layer is, for example, 0.1% by weight or more, 1% by weight or more, 50% by weight or less, 20% by weight or less, and 10% by weight or less. Under the action of the optical resonator structure, the stimulated emission light generated by the laser active material is emitted to the outside as laser light. In an embodiment of the present invention, the laser light originating from the laser active material is diffracted by the supercell structure of the optical resonator structure and is emitted to the outside as diffracted light. At this time, the light emitted from the organic semiconductor laser device may include light emitted from the host material. Light derived from laser-active materials can be the main component.

Other layers in the organic layer The organic layer may be formed of only the light amplification layer, or may have one or more organic layers other than the light amplification layer. Examples of organic layers include electron injection layers and hole injection layers. The smaller the number of heterointerfaces of the organic layer, the better the performance of the electrically pumped organic semiconductor laser device. Therefore, the number of organic layers is, for example, 3 or less, 2 or less, or 1 or less. When the electrically pumped organic semiconductor laser device has more than two organic layers, for example, the thickness of the light amplification layer is greater than 50% of the total thickness of the organic layers, such as greater than 60% and greater than 70%. When the electrically pumped organic semiconductor laser device has two or more organic layers, the total thickness of the organic layers may be, for example, more than 100 nm, more than 120 nm, or more than 170 nm, and may be less than 370 nm, less than 320 nm, or less than 270 nm. The refractive index of the electron injection layer and the hole injection layer may be smaller than the refractive index of the light amplification layer. When configuring the electron injection layer, a substance that promotes electron injection into the light amplification layer may be added to the electron injection layer. When configuring the hole injection layer, a substance that promotes hole injection into the light amplification layer can be added to the hole injection layer. Such substances may be organic compounds or inorganic substances. For example, the inorganic substance used for the electron injection layer includes, for example, an alkali metal such as Cs, and its concentration in the electron injection layer containing an organic compound may be, for example, 1% by weight or more, 5% by weight or more, or 10% by weight or more, and may 40% by weight or less or 30% by weight or less. The thickness of the electron injection layer may be, for example, 3 nm or more, 10 nm or more, or 30 nm or more, and may be 100 nm or less, 80 nm or less, or 60 nm or less. The method of forming the light amplification layer and other layers of the organic layer is not particularly limited, and each of the organic layers can be produced by any method of dry method or wet method. The total thickness of the organic layer including the amplification layer is, for example, 80-350 nm, 100-300 nm, and 150-250 nm.

other layers The organic semiconductor laser device of the present invention may only consist of an optical resonator structure and an organic semiconductor layer, or may further include other layers. Other layers include a transparent protective layer. A transparent protective layer is disposed on the side of the organic layer opposite to the optical resonator structure. The transparent protective layer has the function of protecting the organic layer. The transparent protective layer may be formed of a substantially transparent material. Examples of materials used for the transparent protective layer include fluorine-containing resin and sapphire glass. A laminate (fluorine-containing resin/sapphire glass) in which sapphire glass is laminated on fluorine-containing resin coated on the surface of the organic layer can be used as a transparent protective layer. As a commercially available resin, for example, CYTOP (AGC Chemicals) can be used.

In the organic semiconductor laser device of the present invention, the laser beam may be emitted from the side of the optical resonator structure opposite to the organic layer, or may be emitted from the side of the transparent protective layer opposite to the organic layer. Since the organic semiconductor laser device of the present invention includes an optical resonator structure having at least one of elongated (WS1+WS2), shortened WL, elongated (WS1+WL+WS2) and two or more supercell structures, Therefore exhibits low laser threshold. Furthermore, in one embodiment of the present invention, the organic semiconductor laser device emits split laser beams with a narrow angular difference between the diffraction angles of the diffracted beams. Therefore, the organic semiconductor laser device can be effectively used as a structured light illumination device for detecting 3D geometric shapes. In this case, the angle difference between the diffraction angles of the two diffraction beams with the closest emission angles among the two or more diffraction beams with different diffraction angles is 8° or less, for example, 7° or less and below 6°.

Applications of organic semiconductor laser devices As described above, the organic semiconductor laser device of the present invention exhibits a low oscillation threshold and a narrow diffraction angle of laser emission. Therefore, the organic semiconductor laser device of the present invention can be used as a structured light irradiation device for detecting 3D geometric shapes, and can be effectively used in biological sensors, structured light irradiation devices, optical sensing devices and face recognition devices.

Further detailed description of the present invention The present invention will be described in further detail below. Controlling the laser emission angle in laser devices is necessary for many optoelectronic and photonic applications such as light sensing and display. In this specification, the optical diffraction pattern of a laser beam in a one-dimensional sampled distributed feedback (1D-DFB) resonator with organic gain medium is studied. The grating is composed of a supercell with repetitions of mixed-order sampling gratings surrounding a second-order grating. Experimental results show that the diffraction angle of the laser beam is quite diverse depending on the supercell structure. It has been experimentally and theoretically confirmed that the distance between the diffraction angles (θ) of the laser beam is inversely proportional to the length of the supercell. By adjusting the length of the supercell and the lengths of the first- and second-order regions, the spacing θ is adjusted from 0.1° to 43° under different arc emission modes. As θ decreases, i.e. longer the first-order region, a significant reduction in laser threshold is obtained, resulting in a minimum laser threshold of 2.5 ± 0.1 μJ/cm ² using a ~3.5 ns long pulse width excitation source.

Hereinafter, the features of the present invention will be described in more detail with reference to working examples. In this work, the optical diffraction pattern and laser threshold in a one-dimensional (1D)-sampled DFB resonator with an organic gain layer are studied. In recent OSLDs (organic semiconductor laser diodes) with mixed-order DFB structures, it was found that light is diffracted at different angles and each angle between the diffracted beams is 10° (in the remainder of this specification , the angle between the diffracted beams is called the "diffraction angle"). Certain arcs enhance the laser emission pattern at ^each 10° diffraction angle14. The relationship between the length of the supercell and the diffraction angle is theoretically established, but the experimental proof and potential effects such as lowering the laser threshold have not been fully studied. In particular, for the organic layer, diffraction angle control for obtaining higher resolution has not yet been performed. Therefore, various mixed-order sampling DFB structures with different supercell lengths and first- and second-order region lengths were designed and fabricated to solve this angle problem and reduce the laser threshold.

[Example 1] Grating design The DFB structure used in the present invention is composed of a repeated supercell having a mixed-order grating, that is, a second-order grating is sandwiched on both sides by a first-order grating (Fig. 4). The length of the first-order DFB region varies between 1,632nm and 27,200nm. As the organic gain medium, a guest:host system of 6wt%-BSBCz:CBP was used because it provides optimal laser behavior. ¹⁵ Fourier imaging spectroscopy is also used to measure the diffraction angle of the emitted laser beam. In a DFB resonator, optical feedback occurs due to the coupling between forward and backward propagating waves. ^16This coupling is maximum for a specific wavelength that satisfies the following Bragg conditions. mλ _Bragg =2n _eff Λ (1) Among them, m is the diffraction order, λ _Bragg is the Bragg resonance wavelength, n _eff is the effective refractive index of the waveguide, and Λ is the grating period. In the case of second-order gratings, m is equal to 2, and in the case of first-order gratings, m is equal to 1. In addition, the light diffraction based on the supercell is explained by the following Fraunhofer diffraction law. nλ ₀ =Λ _SC ∙sinθ _m (2) Among them, n is the diffraction order, λ ₀ is the laser emission near the Bragg wavelength, Λ _SC is the length of the supercell, and θ _m is the diffraction angle. According to this formula, the diffraction angle is inversely proportional to the length of the supercell. In the DFB resonator design, the selected Bragg wavelength is 465 nm, and the peak wavelength of the amplified self-emission (ASE) spectrum of the BSBCz:CBP film has a peak at 465 nm (Figure 11). DFB resonators are constructed from repeating supercells. Each supercell is composed of one second-order grating surrounding two first-order gratings. The periods of the first-order and second-order DFB gratings are 136 and 272 nm respectively (Figure 4(a)). The periodicity length was determined by testing standard second-order DFB devices with different periodicity lengths with the same device structure (e.g., total thickness and gain medium), and the best candidate showing the lowest optical threshold was obtained (Figure 12 (b)). Then, by dividing the length of the second-order periodicity by 2, the first-order period is automatically obtained. The empirical effective refractive index is characterized as 1.71. Then, a mixed-order DFB with the ratios of 4:12, 4:36 and 4:200 (second order: first order) and the same second-order period number 4 (dark blue) in each supercell is formed (Figure 4(b) ). As a first candidate, a structure with a ratio of 4:12 was used for the first OSLD structure and it was determined to use this structure as a reference. The first-order lengths of other candidates are larger than those of the 4:12 ratio structure, suggesting that the supercell length is lengthened by increasing the first-order area. As shown in Figure 4(b), the specific lengths of the supercell are 2,720 nm at the ratio of 4:12, 5,984 nm at 4:36, and 28,288 nm at 4:200.

Device Fabrication During the fabrication of organic semiconductor laser (OSL) devices, mixed-stage DFBs were prepared on glass substrates covered with sputtered SiO ₂ with a thickness of 70 nm. First, cleaning was performed by ultrasonic treatment using acetone and boiling isopropyl alcohol in sequence. After solvent cleaning, UV ozone treatment was performed for 15 minutes. In order to make the _SiO2 surface hydrophobic, hexamethyldisilazane (HDMS) was spin-coated at 4000 rpm for 15 s and then annealed at 120 °C for 2 min. Then, the light base agent solution prepared by mixing ZEP-520A and ZEP-520A-7 (ZEON) in a ratio of 1:2 was spin-coated at 4,500 rpm for 30 seconds. It was then spin-coated on top of the substrate at 300 rpm for 15 seconds and annealed at 180 °C for 4 minutes. The thickness of the resist layer obtained was 50 nm. Finally, the static dissipative material Espacer (Showa Denko KK) was spin-coated at 1500 rpm for 30 s and annealed at 80 °C for 4 min. Then, the DFB grating pattern was drawn on the substrate using an electron beam lithography system ELS-G100 (Elionix). The wafer area is 1×1mm ² . After electron beam exposure, the grating pattern was developed in xylene photosolvent for 1 minute at room temperature. Then, the corrugated resist layer was etched by a reactive ion etching machine RIE-10NR (SAMCO). Here, CHF ₃ gas was first applied for 5 minutes under the conditions of flow rate 30 sccm and power 70 W. After that, the remaining part of the resist layer was cleaned using O ₂ gas at a flow rate of 70 sccm and a power of 100 W for 1 minute. The height of the obtained grating is expected to be 69 ± 5 nm. The grating surface observed by a scanning electron microscope (JSM-7900F, JEOL) is shown in Figure 13. Next, an active layer with a thickness of 200 nm was fabricated on the top of the glass/ _SiO grating by thermal co-evaporation of 6wt%-BSBCz as the guest and CBP as the host, and the device was stored under vacuum for 24 hours to coat on The CYTOP layer, which acts as a protective layer on top of the device, is hardened. The schematic diagram of the OSL structure is shown in Figure 4(c).

Results and Discussion The laser performance of OSL was confirmed on a pulsed light pump derived from nitrogen laser NL100 (thinkSRS Inc.) with a pump wavelength of 337nm and a pulse width of ~3.5ns. The pump beam area is ~2.0×10 ^-3 cm ² (Fig. 10). OSL was emitted from the upper part of the sapphire cover glass in the direction perpendicular to the substrate surface (0°), and the light emission pattern was recorded from the glass substrate side using a multi-channel spectrometer (PMA-50 manufactured by Hamamatsu) at 0° (Fig. 7).

Emission Diffraction Angle Measurement First, the photon band diagram of the angle-dependent emission, that is, DFB OSL, was performed to determine the Fraunhofer diffraction of the three grating designs. The photon energy band diagram was measured using a Fourier imaging spectroscopy system (Figure 8). The measurement system has an objective lens and a Fourier lens, which can collect multiple diffraction orders within the angle θ range of -23° to 23°. Details of the experimental setup are described in the supporting material. A nitrogen laser NL100 was used for excitation, and a polarizer was used to separate TE and TM modes. The photon band diagrams of mixed-order sampling DFBs with ratios of 4:12, 4:36 and 4:200 are shown in Figure 5. These photon band diagrams show how the optimal coupling wavelength (the Bragg wavelength) changes with angle, plotting multiple bands that intersect at specific angles. In the case of a simple structure with only 1 second-order grating, only 2 energy bands were found to cross each other at 0°, which has been well confirmed in previous studies. ¹⁷ Figure 5(a) to Figure 5(c) show the photons of OSL with ratios of 4:12, 4:36 and 4:200 (the corresponding supercell periods are 2,720nm, 5,984nm and 28,288nm respectively) Can bring. The spectra show characteristic spectral and angular narrowing derived from the photon band structure. Above the threshold, an angular narrowing in the direction perpendicular to the grating occurs corresponding to the diffracted laser beam. The beam shape in the direction parallel to the grating is fan-shaped. ¹⁸ As shown in Figure 5(a) to Figure 5(c), near the laser threshold, the photon energy band diagrams of the three OSLs clearly show multiple energy bands crossing at different equidistant angles. In the angle range of -20°<θ<+20°, the photon energy bands are observed to cross at different wavelengths and equidistant angles. Therefore, the appearance of additional photon energy bands in OSL is due to the addition of the second-order periodicity of Fraunhofer diffraction, that is, the period of the supercell (an example of the photon energy band of a single periodic structure is shown in Figure 15). The angle between the two diffracted beams satisfies Fraunhofer's law (Eq.2), and a photon stop band will appear at the intersection of each photon energy band. Laser oscillations occur at the band edge of this photonic bandgap because of the presence of a high quality factor at the band edge, as previously documented in the literature. ¹⁹ It can be observed that the angle between the two laser beams is inversely related to the length of the supercell as predicted by Franchise and Feil's law (Eq. 2). Table 1 (No. 4, 5 and 6) shows that there is excellent agreement between measured angles and calculated angles using Fraunhofer's law (Eq. 2) for diffracted laser beams in different structures.

Table 1. Summary of average diffraction orders. Nine different OSL devices were prepared that systematically varied the number of periods of the first- and second-order DFBs. No. Number of cycles of first-order DFB Number of cycles of second-order DFB Supercell length (μm) Second order: first order ratio θ _calc. (°) θ _exp. (°) 1 3 1 0.680 4:12 43.1 43.2 2 9 1 1.496 4:36 18.1 19.9 3 50 1 7.072 4:200 3.8 4.2 4 12 4 2.720 4:12 9.8 10.8 5 36 4 5.984 4:36 4.5 4.9 6 200 4 28.288 4:200 0.9 1.0 7 108 36 24.480 4:12 1.1 1.3 8 324 36 53.856 4:36 0.5 0.5 9 1800 36 254.592 4:200 0.1 0.1

[Example 2] Mixed-order sampled DFBs were further fabricated using second-order DFBs (1 period and 36 periods) in each supercell with different first-order DFB periods by maintaining the ratios 4:12, 4:36, and 4:200. The experimental angles and calculated angles of diffraction are shown in Table 1 (No. 1, 2, 3 (1 period) and 7, 8, 9 (36 periods)), and the photon energy band diagrams are shown in Figures 16 and 17. In Table 1, by lengthening the supercell length, a tendency for the diffraction angle to become narrower can be observed in each comparison, and in the case of No. 9. it converges to the minimum value of 0.1°. Here, the diffraction angle is controlled by the length of the supercell and the lengths of the first- and second-order DFB regions. As an example, the ratios 1:3, 1:9 and 1:50 (No. 1, 2 and 3) shown in Table 1 represent highly separated far-field emissions with extremely large diffraction angles (Figure 16). On the other hand, the ratios 36:108, 36:324, and 36:1800 (No. 7, 8, and 9) shown in Table 1 represent highly localized far-field emission with extremely low diffraction angles (Fig. 17).

OSL laser threshold measurement Based on photon band diagram measurement, ratios 4:12, 4:36 and 4:200 (No. 4, 5 and 6) were determined to be the best candidates for high-resolution and wide-angle lasers item. Therefore, the laser threshold measurement was performed using a 0° measurement system. The laser threshold is determined based on the measured input-output optical power characteristics of the OSL. Figure 6(a), Figure 6(b) and Figure 6(c) show the below-threshold and above-threshold emission spectra of OSL using mixed-order sampling DFB resonators with different ratios of first-order and second-order. Below the threshold, the photon stopband widths for ratios 4:12, 4:36, and 4:200 are approximately 2.86, 3.89, and 4.60 nm, respectively. The center of the photon stop band is located at 465nm, and the photon stop band centers of the three OSLs are all the same. Figure 6(d) shows the changes in laser threshold and photon stopband width as a function of the length of the first-order region in three different proportions. As the length of the first-order grating increases, a decrease in the laser threshold and an increase in the stopband width can be observed. Therefore, the OSL with a mixed-order sampled DFB resonator with a ratio of 4:200 shows a threshold 8 times lower (2.5±0.1μJ/ ^cm2 ) and wider than the 4:12 ratio (21.4±1.1μJ/ ^cm2 ). stop band. A relatively long pulse width excitation source of ~3.5 ns was used. This reduction in laser threshold is believed to be due to the enhancement of planar light feedback caused by the lengthened first-order grating length. The amount of light return is determined by quantifying the intensity of backward Bragg scattering using a coupling constant. The coupling constant is proportional to the stopband width and is explained using the coupling theory proposed by Kogelnik and Shank. ¹⁶ At one edge of the stopband, the laser is able to oscillate and the width of the stopband is a measure of the strength of the feedback. Therefore, the reduction of the laser threshold can be achieved by enhancing the coupling effect, that is, by increasing the coupling constant by lengthening the first-order length. Below the threshold, the emission spectrum shows additional features that can be imparted by the Bragg tilt. These features are clearly observed in the emissions from OSL at scales 4:12 and 4:36. Features were observed at 450nm for OSL with a ratio of 4:12. OSL with a ratio of 4:36 has features observed at 451, 458, 473 and 481nm. However, in the case of OSL with a ratio of 4:200, somehow the spectrum shows a very faint feature at 460nm, but it is difficult to resolve this feature due to the presence of noise in the emission spectrum. Additional features observed in the 0° emission of OSLs with ratios 4:12 and 4:36 at different wavelengths in Figures 6(a) and 6(b) are also observed in the photon band diagram in Figure 5 arrive. The emission spectrum at the 0° angular axis is shown on the right side of the photon band diagram. In the case of OSL with a ratio of 4:12, the energy bands cross at three wavelengths: 435nm, 461nm, and 503nm. At the latter two wavelengths, a tilt angle is also observed in the 0° emission spectrum, which is due to the overlap of these tilt angles with the emission spectrum. In the case of OSL with a ratio of 4:36, the energy bands cross at 4 wavelengths: 447, 461, 478 and 498 nm, and tilt angles are also observed in the 0° emission spectrum. This is due to the fact that these tilt angles are consistent with the emission spectrum. of overlap. For scale 4:200, the photon band diagram has a large amount of tilt due to the complex number of points where the photon bands intersect. These tilt angles constitute additional features resulting from photon energy bands crossing at different angles in addition to different wavelengths. The laser threshold of the additional tilt angle is higher than the main stop band that satisfies the Bragg condition. This is simply because the gain material BSBCz doped film has the highest gain near the Bragg wavelength, and the greater the difference between the available oscillation wavelength and this wavelength, the lower the gain. In addition, taking into account the tendency of the diffraction angle, when the supercell length of the DFB becomes longer, it can be expected to achieve lower diffraction angles and thresholds. In summary, in order to obtain a low threshold, the first-order DFB area needs to be increased, the second-order DFB area needs to have an optimal number of periods, and then the diffraction angle needs to be controlled by controlling the length of the supercell.

Conclusion A sampled mixed-order DFB OSL was designed and studied to control the diffraction angle and threshold of the organic layer based on Fraunhofer's law. First, the supercell length is controlled by changing the ratio of the second order to the first order of the sampling mixed order DFB. A total of 9 DFBs with different structures were fabricated and tested. Based on the angle-dependent emission measurement results, the laser diffraction angle was adjusted from 0.1° to 43°. This action follows Fraunhofer's law (diffraction angle is inversely proportional to supercell length), and the experimental and calculated diffraction angles show good agreement. Among the 9 DFBs, structures with ratios of 4:12, 4:36 and 4:200 show the widest angular range and low diffraction angle emission. Therefore, mixed-order DFBs sampled at 4:12, 4:36, and 4:200 ratios were selected to further measure the optical pump laser threshold. When the first-order DFB area increases, the laser threshold decreases by 2.5±0.1μJ/cm ² . The 0° emission spectrum shows that the longer the length of the supercell with the longer first-order region, the wider the photon energy gap (ie, the stop band), which indicates stronger lateral feedback. This result provides useful information on how to control the emission diffraction angle of OSL/OSLD with a lower threshold and without using bulky diffractive optical elements, which can be used in a variety of applications, such as biosensing. device, face recognition technology and ToF system based on 2D and 3D structured light.

Supporting materials Part 1 : Construction of measurement system and preparation of equipment ( a ) Construction of laser performance measurement system In this work, two measurement systems were constructed, namely a single-angle measurement system and a Fourier imaging spectroscopy system. . The former is designed to measure the optical threshold and laser spectrum by emitting light in the vertical direction (0°) from the DFB laser device. The pump laser source is nitrogen laser NL100 (thinkSRS Inc., wavelength of 337nm and pulse width of 3.5ns) or Nd:YAG laser (wavelength of 355nm and pulse width of 0.9ns). Use 3 ND filters with adjustable density to finely control pump sources and map light thresholds. Filter the coarsely pumped light through the aperture to draw a clear, circular beam shape. Finally, a 355nm cutoff filter was placed behind the sample and in front of the PMA50 detector to cut off light sources that would interfere with detection of light emitted from the device. In contrast, the latter is designed to collect and capture wide-angle-dependent photoluminescence (PL) images. The pump laser source is the same as the nitrogen laser NL100 with a single angle measurement system. First, the pump light is intercepted into a circle and a lens is used to control the size of the source beam. Then, the objective lens, Fourier lens and tube lens were placed to collect the widely dispersion emission from the DFB device and transmit it to the spectrometer Shamrock500i (Andor Technology). Set the UV cut filter to cut off the nitrogen pump laser, and finally set the polarizer to filter the output laser to 0° or 90°. In the present invention, the polarizer is basically set to 0° filtering, which removes the very weak second 90° polarization in the image. In the acquisition settings, an exposure time of 0.2 seconds was applied.

( b ) Pump laser source profile. The beam shape of the pump source at the sample position is captured by a WinCamD-LCM CCD camera (Opto Science, inc.) to determine the pump area in the DFB. In the present invention, the sizes of nitrogen laser and Nd:YAG laser were measured. The figure below shows the top view and diagonal view images. In the top view, the x and y axes are marked with two outlines. Each profile was approximated by Gaussian fitting, and the profile width was determined using the 13.5% peak as a standard. Both laser sources have elliptical beam shapes, and each axis is controlled to not exceed 1000nm (the width of the DFB size designed for this work).

( c ) Absorption, PL and ASE of 6wt% BSBCz:CBP film. In order to obtain consistent optical properties, the film was fabricated by a thermal co-evaporation system. The parameters involved in this process include film thickness, UV-visible absorption (Abs) spectrum, photoluminescence (PL) spectrum, amplified self-emission (ASE) spectrum and photoluminescence quantum yield (PLQY). First, the film thickness measured by Dektak XT stylus profiler (BRUKER) was 202±2nm. When estimating the doping ratio, the peak wavelength of the ASE spectrum is used because the wavelength shifts depending on the molecular weight of the host material and guest material. Secondly, the Abs spectrum and PL spectrum were recorded by LAMDA950 (PerkinElmer) and FluoroMax-4 (Horiba) respectively (Figure 11). Third, the estimated ASE wavelength of 6wt% is 465nm, and this parameter was measured by PMA50 (Hamamatsu Photonics). Finally, the PLQY of the film was measured by Quantaurus-QY (Hamamatsu Photonics) and was 93% at an excitation wavelength of 330 nm.

( d ) Periodic optimization of mixed-order DFB resonator For simple comparison, only second-order DFB is used to optimize the periodic length of the grating. Five candidates with second-order period lengths of 260nm, 264nm, 272nm, 276nm and 280nm were selected. All candidates have a duty cycle of 0.5. In order to determine the best one, all second-order DFB devices with a BSBCz:CBP (6wt%, 200nm thickness) film evaporated on the DFB were fabricated and their laser spectra and thresholds were measured. In this experiment, an Nd:YAG laser pump source was used. Figure 12(a) shows the laser spectrum of the device with each candidate DFB and the ASE spectrum of the BSBCz:CBP film without DFB. Compared with the SE spectrum which has a wide FWHM of 7.20nm, these five laser spectra all show an extremely narrow full width at half maximum (FWHM) of 0.14~0.16nm. Among the candidates, the device with a second-order period length (Λ) of 272 nm is expected to show the lowest optical threshold due to its largest overlap with the ASE spectrum, indicating that the best gain effect is obtained in the DFB resonator. This opinion is verified through the measurement and comparison of the laser threshold shown in Figure 12(b). Therefore, the supercell length of the sampled mixed-order DFB in the present invention is determined based on the optimized periodicity length, that is, the second order of 272 nm and the first order of 136 nm.

( e ) SEM image of the DFB structure . In order to compare the structural differences, the first-order and second-order periodic lengths are fixed at 136 nm and 272 nm, respectively. Then, three different structures with different supercell lengths and the same 4-period second-order grating in each supercell were photographed by scanning electron microscopy (SEM). Gold sputtering at 40 mA power for 60 seconds was performed to improve the conductivity of the SiO _grating surface. Figure 13 (a, b, c) shows the geometric shapes of sampled mixed-order gratings with ratios of 1:3, 1:9 and 1:50 respectively. On the same day, the additional sampling mixed order DFB mentioned in the last part of the specification (1-cycle and 36-cycle second-order DFB regions, and different ratios (1:3, 1:9 and 1:50) were manufactured under the same conditions ).

Part 2 : Details of the main experiments ( a ) 0° emission spectrum measurements Each output emission was recorded using a single-angle measurement system (Fig. 7) with PMA software published by Hamamatsu Photonics. The software setting parameters used to collect data include 2 factors: an exposure time of 200ms and averaging 5 times per frame. In the first stage, the size of the pump laser beam at the specimen position is captured and measured as shown in part 1(b). Then, calculate the beam area in cm ² units by using the formula for the area of an ellipse. Then, the sample was placed on the right side of the beam size acquisition position, and the wavelength power (count) was measured. During the measurement process, the pump laser power is increased by gradually switching the concentration of the ND filter until the output power reaches peak saturation. Each frame captured using an independent density ND filter was then recorded. Finally, the specimen was replaced with a nanojoule meter (Ophir Photonics) to record all pump powers used (in μJ units). In the next step, each acquisition data is collected and aggregated to represent the laser threshold (Figure 14). The figure includes three factors: excitation intensity (x-axis), normalized emission intensity (y-axis), and FWHM (second y-axis). First, each excitation intensity point is expressed by the following formula S1. I _exc = (S1) Among them, the pump power (μJ) is E, the calculated pump beam area (cm ² ) is A, and the absorption coefficient is c. The coefficient c is represented by 1-10 ^-Abs , where "Abs" refers to the absorbance of the gain film previously measured by LAMDA950 (PerkinElmer). The specific Abs parameter represents the excitation wavelength of the pump laser source, which is 337nm in the case of nitrogen laser source (NL100, thinkSRS Inc.) and 355nm in the case of Nd:YAG laser source (maker). In addition, the normalized emission intensity is summarized by counting the emission power. Finally, label the FWHM on the right side of the y-axis. All graphs are expressed on a logarithmic scale, and the single intersection point formed by 2 approximate straight lines based on the normalized emission intensity trend is defined as the laser threshold point. In order to verify the reproducibility of the threshold, three samples of each DFB structure (4-cycle second-order DFB region, and ratios of 1:3, 1:9 and 1:50) were manufactured and tested simultaneously under the same conditions. Laser devices etc.

Table 2. Summary of thresholds for 4-period second - order DFBs and sampled mixed-order DFBs with different proportions Raster scale First test E _th (μJ/cm ² ) Second test E _th (μJ/cm ² ) The third test E _th (μJ/cm ² ) Error ±(μJ/cm ² ) 1:3 22.5 22.5 19.3 1.1 1:9 7.6 9.5 8.8 0.6 1:50 2.4 2.8 2.4 0.1

Table 3. Summary of FWHM with 4-period second - order DFB and sampled mixed-order DFB with different proportions Raster scale First trial FWHM (nm) Second trial FWHM (nm) Third test FWHM (nm) Error±(nm) 1:3 0.16 0.15 0.16 0 1:9 0.14 0.15 0.15 0 1:50 0.15 0.15 0.15 0

( b ) Fourier imaging spectra of sampled mixed-order DFB lasers with only 1 or 36 second-order gratings in each supercell . In addition to the main experiments using 4-period second-order DFB regions and different ratios of mixed-order DFB values, we also made The characteristics of DFB OSL with 1-period and 36-period second-order DFB regions and different ratios (1:3, 1:9 and 1:50) were determined. Figures 15 and 16 show photon energy band diagrams, as well as theoretical and experimental diffraction angles. The second peak (red dotted line area) in the above threshold value in Figure 15(a) and Figure 15(b) is noise. A second-order DFB OSL was fabricated and measured for comparison. Figure 15 shows the photon band diagram of OSL. [Industrial availability]

By utilizing the method of the present invention, the laser threshold of the organic semiconductor laser device can be reduced and the diffraction angle of the laser emission of the organic semiconductor laser device can be narrowed. Therefore, the organic semiconductor improved by the method of the present invention can be effectively used as a structured light irradiation device for detecting three-dimensional shapes. Therefore, the present invention has high industrial applicability. [refer to]

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1a: Lattice groove 1b: Lattice groove 2a: Lattice groove 2b: Lattice groove 3a: Lattice groove 3b: Lattice groove 10: Optical resonator structure FSP: First short pitch periodic structure LP: Long pitch Periodic structure SC1: Super cell structure SC2: Super cell structure SC3: Super cell structure SSP: Second short pitch periodic structure WL ₁ : The length of the super cell structure WL ₂ : The length of the super cell structure WL ₃ : The length of the supercell structure WS1: The length of the first short-pitch structure FSP in the x direction WS2: The length of the second short-pitch structure FSP in the x direction WL: The length of the long-pitch structure LP in the x direction Length Λ1: the distance between the side surfaces of adjacent lattice grooves 1a and 1b Λ2: the distance between the side surfaces of adjacent lattice grooves 2a and 2b ΛL: the distance between the side surfaces of adjacent lattice grooves 3a and 3b

FIG. 1 is a schematic plan view showing an example of an optical resonator structure used in the present invention. FIG. 2 is a schematic top view showing an optical resonator structure having more than three supercell structures of different lengths. FIG. 3 is a simulation result of the angle dependence of laser emission of a laser diode having the optical resonator structure shown in FIG. 2 . Figure 4(a) is a scanning electron microscopy (SEM) image of the second-order and first-order sampling gratings in the mixed-order DFB with a ratio of 4:12. Figure 4(b) is the second-order and first-order sampling in the mixed-order DFB. Schematic top view of gratings with ratios of 4:12, 4:36 and 4:200 (Λ _SC corresponds to the length of one supercell, which is the sum of one second-order and two first-order sampling gratings), Figure 4 (c ) Cross-sectional view of an organic semiconductor laser (OSL) device encapsulated with CYTOP and a sapphire glass cover. Figure 4(d) shows the 4,4'-bis[(N-carbazole)styrene] linkage as the gain medium. The structural formula of benzene (BSBCz), and 4,4'-bis(N-carbazolyl)biphenyl (CBP) as the main body. Figure 5(a) to Figure 5(c) are mixed-stage DFB devices with second-order DFB (4 cycles). The ratios are (a) 4:12, (b) 4:36 and (c) 4:200 (second-order: First-order) photon band diagram (color image), PL spectrum at θ = 0° (right), and far-field emission pattern (lower side). Figure 6 (a) to Figure 6 (c) are mixed-stage sampling DFB devices (No. 4, 5 and 6 are shown in Table 1). The ratios when sampling is emitted at 0° are (a) 4:12, (b) PL (black) and laser (red) spectra at 4:36 and (c) 4:200. Figure 6(d) shows the stop band width and laser threshold depending on the number of first-order periods in the supercell. Figure 7 is a schematic diagram of a single-angle measurement system. Figure 8 is a schematic diagram of the Fourier imaging spectroscopy system. Figure 9 is an image showing the beam shape of the NL100 nitrogen laser. Figure 10 is an image showing the beam shape of Nd:YAG laser. Figure 11 is a graph showing the UV-visible absorption (blue line), photoluminescence (red line) and amplified self-emission (black dotted line) spectra of the BSBCz:CBP (6wt%) film. Figure 12(a) and Figure 12(b) show the laser performance of five second-order period lengths compared with (a) laser spectrum and (b) laser threshold. Figure 13(a) to Figure 13(c) are scanning electron displays of a 4-period second-order DFB region with sampling mixed-order DFB ratios of (a) 1:3, (b) 1:9 and (c) 1:50. Micro (SEM) image. Figure 14(a) to Figure 14(c) are the second-order DFB area with 4 periods. The ratio of sampled mixed-order DFB is (a) 1:3 (3 tests), (b) 1:9 (3 tests) and (c) summary of laser thresholds at 1:50 (3 trials). Figure 15 is the photon band diagram of the unsampled second-order DFB OSL. Figure 16(a) to Figure 16(c) are the photon energy band diagrams of the 1-period second-order DFB region and different ratios (a) 1:3, (b) 1:9 and (c) 1:50 and their 0° cropping Photoluminescence spectrum (right) and far-field emission pattern (lower). Figure 17(a) to Figure 17(c) are the photon energy band diagrams of the 36-period second-order DFB region and different ratios (a) 1:3, (b) 1:9 and (c) 1:50 and their 0° cropping Photoluminescence spectrum (right) and far-field emission pattern (lower).

1a:Lattice groove

1b:Lattice groove

2a:Lattice groove

2b:Lattice groove

3a:Lattice groove

3b:Lattice groove

10: Optical resonator structure

FSP: First Short Pitch Periodic Structure

LP: Long pitch periodic structure

SSP: Second Short Pitch Periodic Structure

WS1: The length of the first short pitch structure FSP in the x direction

WS2: The length of the second short pitch structure in the x direction

WL: The length of the long pitch structure LP in the x direction

Λ1: The distance between the side surfaces of adjacent lattice grooves 1a and 1b

Λ2: The distance between the side surfaces of adjacent lattice grooves 2a and 2b

ΛL: the distance between the side surfaces of adjacent lattice grooves 3a and 3b

Claims (51)

A method for improving an organic semiconductor laser device. The aforementioned organic semiconductor laser device includes an optical resonator structure and a light amplification layer composed of an organic semiconductor, wherein The aforementioned optical resonator structure has at least one supercell structure, and the aforementioned supercell structure has a first short-pitch periodic structure, a long-pitch periodic structure, and a second short-pitch periodic structure, The first short-pitch periodic structure is arranged adjacent to one end of the long-pitch periodic structure, and the second short-pitch periodic structure is arranged adjacent to the other end of the long-pitch periodic structure, (i) the direction orthogonal to the lattice grooves of the aforementioned first short-pitch periodic structure, (ii) the direction orthogonal to the lattice grooves of the aforementioned long-pitch periodic structure, and (iii) the aforementioned second short section. On a straight line from at least two of the directions orthogonal to the lattice grooves of the periodic structure, The aforementioned methods include at least one of the following: (1) Extended (WS1+WS2), (2) Shorten WL, (3) Extended (WS1+WL+WS2) and (4) Repeat the aforementioned supercell structure, WS1 represents the length of the first short-pitch periodic structure in the direction orthogonal to the lattice groove, and WS2 represents the length of the second short-pitch periodic structure in the direction orthogonal to the lattice groove. , WL represents the length in the direction orthogonal to the lattice groove of the aforementioned long-pitch periodic structure. For example, the method of claim 1 is implemented in (1). For example, the method of claim 1 is implemented in (2). For example, the method of claim 1 is implemented in (3). For example, the method of claim 1 is implemented in (4). For example, the method of claim 1 implements (1) and (2). For example, the method of claim 1 implements (1) and (3). For example, the method of claim 1 implements (2) and (3). For example, the method of claim 1 implements (1), (2) and (3). As in claim 6, the method is further implemented in (4). For example, the method of request item 1 is to adjust (WS1+WS2)/WL to 4 or more. For example, the method of claim 1 adjusts (WS1+WS2) to 1 μm or more. Like the method of claim 1, WL is adjusted to 10 μm or less. Like the method of claim 1, adjust (WS1+WL+WS2) to 2 μm or more. For example, the method of request item 1 satisfies WS1=WS2. Such as the method of request item 1, where (i) the direction orthogonal to the lattice grooves of the aforementioned first short-pitch periodic structure, (ii) the direction orthogonal to the lattice grooves of the aforementioned long-pitch periodic structure, and (iii) the aforementioned second short section. The directions orthogonal to the lattice grooves of the periodic structure are all on a straight line. The method of claim 1, wherein the first short-pitch periodic structure is in contact with one end of the long-pitch periodic structure, and the second short-pitch periodic structure is in contact with the other end of the long-pitch periodic structure. One end is in contact. Such as the method of request item 1, where The aforementioned periodic structures include gratings composed of ridges and grooves. Such as the method of request item 18, where The aforementioned first short-pitch periodic structure and the aforementioned second short-pitch periodic structure are first-order gratings, and the aforementioned long-pitch periodic structure is a second-order grating. Such as the method of request item 1, where The aforementioned method is used to reduce the laser threshold. Such as the method of request item 1, where The aforementioned method is used to narrow the diffraction angle of laser emission. Such as the method of request item 1, where The aforementioned method is used to reduce the laser threshold and narrow the diffraction angle of laser emission. Such as the method of request item 1, where The aforementioned method is used to design organic semiconductor laser devices. Such as the method of request item 1, where The aforementioned method is used to evaluate organic semiconductor laser devices. Such as the method of request item 1, where The aforementioned method is used to manufacture organic semiconductor laser devices. A program for implementing the method of claim 1. A computer used to implement the method of claim 1. An organic semiconductor laser device manufactured by the method of claim 25. An organic semiconductor laser device, which includes an optical resonator structure and a light amplification layer composed of organic semiconductors, wherein The aforementioned optical resonator structure has at least one supercell structure, and the aforementioned supercell structure has a first short-pitch periodic structure, a long-pitch periodic structure, and a second short-pitch periodic structure, The first short-pitch periodic structure is arranged adjacent to one end of the long-pitch periodic structure, and the second short-pitch periodic structure is arranged adjacent to the other end of the long-pitch periodic structure, (i) the direction orthogonal to the lattice grooves of the aforementioned first short-pitch periodic structure, (ii) the direction orthogonal to the lattice grooves of the aforementioned long-pitch periodic structure, and (iii) the aforementioned second short section. On a straight line from at least two of the directions orthogonal to the lattice grooves of the periodic structure, The aforementioned organic semiconductor laser device has at least one of elongated (WS1+WS2), shortened WL, elongated (WS1+WL+WS2) and two or more supercell structures, where WS1 is represented by the aforementioned first short section. The length of the periodic structure in the direction orthogonal to the lattice grooves, WS2 represents the length of the second short-pitch periodic structure in the direction orthogonal to the lattice grooves, and WL represents the length of the periodic structure in the direction orthogonal to the lattice grooves. The length of the linear structure in the direction orthogonal to the lattice grooves. The organic semiconductor laser device of claim 28, wherein The aforementioned optical resonator structure has two or more supercell structures arranged in such a way that directions orthogonal to the lattice grooves of the two or more supercell structures are aligned in a straight line. The organic semiconductor laser device of claim 30, wherein WS1, WL and WS2 of the above two or more supercell structures are the same. The organic semiconductor laser device of claim 30, wherein The lengths of the above two or more supercell structures in the direction orthogonal to the lattice grooves are random. The organic semiconductor laser device of claim 30, wherein The aforementioned optical resonator structure has more than 10 supercell structures. The organic semiconductor laser device of claim 28, wherein The aforementioned first short-pitch periodic structure, the aforementioned long-pitch periodic structure, and the aforementioned second short-pitch periodic structure have grooves with a depth less than 75 nm. The organic semiconductor laser device of claim 28, wherein The aforementioned first short pitch periodic structure, the aforementioned long pitch periodic structure and the aforementioned second short pitch periodic structure have a distributed feedback (DFB) structure. The organic semiconductor laser device of claim 35, wherein Each distributed feedback (DFB) structure is selected from the group consisting of first-order DFB structures, second-order DFB structures, third-order DFB structures and higher-order DFB structures. The organic semiconductor laser device of claim 28, wherein The aforementioned first short-pitch periodic structure, the aforementioned long-pitch periodic structure and the aforementioned second short-pitch periodic structure are made of insulating materials. The organic semiconductor laser device of claim 28, wherein The aforementioned first short-pitch periodic structure, the aforementioned long-pitch periodic structure, and the aforementioned second short-pitch periodic structure have periodically arranged ridge portions made of an insulating material on an insulating substrate. The organic semiconductor laser device of claim 38, wherein The ridge portion and the insulating substrate are made of different insulating materials. The organic semiconductor laser device of claim 38, wherein The ridge portion is made of silicon dioxide, and the insulating substrate is made of a glass substrate. The organic semiconductor laser device of claim 38, wherein The surface of the insulating substrate is exposed at the bottom of the groove. The organic semiconductor laser device of claim 28 further has an organic layer on the surface of the aforementioned optical resonator structure. The organic semiconductor laser device of claim 42 further includes a transparent protective layer on the side of the organic layer opposite to the optical resonator structure. As claimed in claim 42, the organic semiconductor laser device emits a laser beam from the side of the organic layer opposite to the optical resonator structure. As claimed in claim 43, the organic semiconductor laser device emits a laser beam from the side of the organic layer opposite to the transparent protective layer. For example, the organic semiconductor laser device of claim 28 emits more than two types of diffracted light with different diffraction angles. The organic semiconductor laser device of claim 46, wherein Among the two or more types of diffracted light, the angle difference between the diffraction angles of the diffracted light with the closest emission angle is 8° or less. The organic semiconductor laser device of claim 28, wherein The aforementioned organic layer contains an organic compound having at least one stilbene unit. The organic semiconductor laser device of claim 28, wherein The aforementioned organic layer contains 4,4'-bis[(N-carbazole)styryl]biphenyl (BSBCz). The organic semiconductor laser device of claim 28, wherein The thickness of the aforementioned organic layer is 80 to 350 nm. A device selected from the group consisting of biosensors, structured light illumination devices, optical sensing devices and face recognition devices, which includes the organic semiconductor laser device of claim 28.

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