Abstract: A display system includes: an image acquisition unit that acquires each of a first image of a work site imaged by a first camera and a second image of the work site imaged by a second camera; a viewpoint position calculation unit that calculates a viewpoint position of worker; a luminance adjustment unit that adjusts luminance of at least one of the first image and the second image based on the viewpoint position; and a display control unit that combines the first image and the second image having the luminance adjusted and causes a display device to display the combined image.

Abstract: An organic electroluminescent device having an anode, a cathode, and a light emitting layer between the anode and the cathode, in which the light emitting layer contains a first organic compound, a second organic compound, and a third organic compound that satisfy the following expression (A), the second organic compound is a delayed fluorescent material, and the third organic compound is a light emitting material, is capable of enhancing the light emission efficiency. ES1(A), ES1(B) and ES1(C) represent a lowest, singlet excitation energy level of the first, second and third organic compound, respectively.

Abstract: An organic electroluminescent device having an anode, a cathode, and a light emitting layer between the anode and the cathode, in which the light emitting layer contains a first organic compound, a second organic compound, and a third organic compound that satisfy the following expression (A), the second organic compound is a delayed fluorescent material, and the third organic compound is a light emitting material, is capable of enhancing the light emission efficiency. ES1(A), ES1(B) and ES1(C) represent a lowest, singlet excitation energy level of the first, second and third organic compound, respectively.

Abstract: An organic electroluminescent device having an anode, a cathode, and a light emitting layer between the anode and the cathode, in which the light emitting layer contains a first organic compound, a second organic compound, and a third organic compound that satisfy the following expression (A), the second organic compound is a delayed fluorescent material, and the third organic compound is a light emitting material, is capable of enhancing the light emission efficiency. ES1(A), ES1(B) and ES1(C) represent a lowest singlet excitation energy level of the first, second and third organic compound, respectively.

Abstract: An organic electroluminescent device having an anode, a cathode, and a light emitting layer between the anode and the cathode, in which the light emitting layer contains a first organic compound, a second organic compound, and a third organic compound that satisfy the following expression (A), the second organic compound is a delayed fluorescent material, and the third organic compound is a light emitting material, is capable of enhancing the light emission efficiency. ES1(A), ES1(B) and ES1 (C) represent a lowest singlet excitation energy level of the first, second and third organic compound, respectively.

Abstract: An organic electroluminescent device having an anode, a cathode, and a light emitting layer between the anode and the cathode, in which the light emitting layer contains a first organic compound, a second organic compound, and a third organic compound that satisfy the following expression (A), the second organic compound is a delayed fluorescent material, and the third organic compound is a light emitting material, is capable of enhancing the light emission efficiency. ES1(A), ES1(B) and ES1(C) represent a lowest singlet excitation energy level of the first, second and third organic compound, respectively.

Abstract: An organic electroluminescent device having an anode, a cathode, and a light emitting layer between the anode and the cathode, in which the light emitting layer contains a first organic compound, a second organic compound, and a third organic compound that satisfy the following expression (A), the second organic compound is a delayed fluorescent material, and the third organic compound is a light emitting material, is capable of enhancing the light emission efficiency. ES1(A), ES1(B) and ES1(C) represent a lowest singlet excitation energy level of the first, second and third organic compound, respectively.

Abstract: An organic semiconductor laser device containing a compound represented by the following formula has a low threshold value for laser emission and has excellent laser characteristics. The ring A, the ring B and the ring C each are a aryl ring or a heteroaryl ring; Y1 is B, P, P?O, P?S, Al, Ga, As, Si—R or Ge—R; R is an aryl group or an alkyl group; X1 and X2 each are O, N—R?, S or Se; R? is an aryl group, a heteroaryl group or an alky group.

Abstract: An organic electroluminescent device having a donor layer containing a donor compound, a spacer layer containing a spacer compound, and an acceptor layer containing an acceptor compound in that order, wherein the donor compound and the acceptor compound are compounds to form an exciplex to radiate delayed fluorescence, and the excited triplet energy of the spacer compound is higher than the excited triplet energy of the exciplex, can be controlled to have different emission wavelengths not requiring change of the combination of the donor compound and the acceptor compound therein.

Abstract: An organic electroluminescent device having a donor layer containing a donor compound, a spacer layer containing a spacer compound, and an acceptor layer containing an acceptor compound in that order, wherein the donor compound and the acceptor compound are compounds to form an exciplex to radiate delayed fluorescence, and the excited triplet energy of the spacer compound is higher than the excited triplet energy of the exciplex, can be controlled to have different emission wavelengths not requiring change of the combination of the donor compound and the acceptor compound therein.

Abstract: An organic light-emitting device containing a host material, a delayed fluorescent material and a light-emitting material satisfying ES1(H)>ES1(F)>ES1(D) has a high light emission efficiency. ES1(H) represents a lowest excited singlet energy level of the host material, ES1(F) represents a lowest excited singlet energy level of the delayed fluorescent material, and ES1(D) represents a lowest excited singlet energy level of the light-emitting material.

Abstract: An organic electroluminescent device having an anode, a cathode, and a light emitting layer between the anode and the cathode, in which the light emitting layer contains a first organic compound, a second organic compound, and a third organic compound that satisfy the following expression (A), the second organic compound is a delayed fluorescent material, and the third organic compound is a light emitting material, is capable of enhancing the light emission efficiency. ES1(A), ES1(B) and ES1(C) represent a lowest singlet excitation energy level of the first, second and third organic compound, respectively.