A hologram for an illumination device for vehicles and a corresponding illumination device are provided. The hologram has a plurality of holographic structures designed for a respectively associated wavelength, wherein the holographic structures have diffraction properties that are identical among one another.

A method for observing a sample by lensless imaging, in which a sample is positioned between a laser diode and an image sensor, the laser diode being supplied with a supply current whose intensity is less than or equal to a critical value. This critical intensity is determined during preliminary operations, during which the intensity is initially greater than a laser threshold of the diode. By observing the image formed at the image sensor, the intensity is decreased until an attenuation of the interference images on the formed image is observed, the critical intensity corresponding to the intensity at which this attenuation is optimum.

There is provided a head-up display for a vehicle having a window. The head-up display comprises a picture generating unit (410) and an optical system (420). The picture generating unit is arranged to output pictures. The optical system is arranged to receive the pictures output by the picture generating unit and project the pictures onto the window (430) of the vehicle to form a virtual image (450, 707) of each picture within a virtual image area (605). The picture generating unit is arranged to output pictures within a cropped picture area such that the virtual image area (605) has a corresponding cropped shape. FIG. 7 illustrates a perspective view of a three lanes road (501,502,503) onto which a virtual image (707) within a cropped virtual image area (605) is overlaid.

Disclosed is a method for digitally generating a hologram in a screen plane of a hologram display device, including: obtaining intensity and depth maps of the scene corresponding to user viewpoint; projecting the points of the intensity map on planes parallel to the screen plane in a reference frame of the screen, one plane associated with one depth value of between minimum and maximum values of the depth map, a point of the intensity map projected on the plane of the planes associated with the depth value of the point in the depth map; compensating for distortion by modifying the planes of the scene, a point of one plane, called image point of an object point by conjugation of the convergent lens, being replaced by the object point; from the modified planes, propagating a complex sampled light wave to the screen plane and summation of the propagated light waves.

The present invention relates to a compound having a novel structure, a photopolymer composition including the compound as a dye, a hologram recording medium produced from the photopolymer composition, an optical element including the hologram recording medium, and a holographic recording method using the hologram recording medium.

A holographic display apparatus includes a light source disposed on a printed circuit board, a display panel diffracting light transferred from the light source, and an optical system disposed between the light source and the display panel. The optical system converts the light incident from the light source into a surface light source.

A hologram for an illumination device for vehicles and a corresponding illumination device are provided. The hologram has a plurality of holographic structures designed for a respectively associated wavelength, wherein the holographic structures have diffraction properties that are identical among one another.

A device for detecting at least one object present in a sample, the device including a light source to emit at least one incident wave at a wavelength λ, a detection volume intended to receive the object, and to receive at least one incident wave, an image sensor positioned to receive at least one scattered light wave obtained by diffraction of the incident wave on the object and a reference wave from the source and not diffracted on the object and to generate a holographic image, and a computer data processing device to digitally reconstruct the object based at least on the holographic image and the wavelength λ. The device also comprises a support comprising patterns organized to form at least one diffraction grating, the grating being periodic and having a pitch P, such that λ/2≤P≤2λ.

There is provided a head-up display having an eye-box comprising a driver monitoring system, picture generating unit and optical system. The driver monitoring system is arranged to illuminate and monitor a driver. The driver monitoring system comprises a first display channel. The picture generating unit is arranged to display a picture on a replay plane. The picture generating unit comprises a second display channel Each display channel comprises a light source, spatial light modulator and controller. Each light source is arranged to emit light. Each spatial light modulator is arranged to receive light from the respective light source and output spatially-modulated light in accordance with a computer-generated hologram displayed on the spatial light modulator to form a respective light pattern on the replay plane. Each controller is arranged to output the computer-generated hologram to the spatial light modulator. The optical system is arranged to relay each light pattern from the replay plane. The optical system comprises an input, output and at least one mirror. The input is arranged to receive light of each light pattern. The output is arranged to output light of each light pattern. The at least one mirror is arranged to guide light from the input to the output along an optical path. The light pattern formed by the first display channel is an infrared light pattern. Each light pattern is a holographic reconstruction.

To obtain a more accurate image by improving a utilization efficiency of light energy while at the same time suppressing with a simpler method distortion that may occur in an inline hologram when a plurality of lights having different wavelengths are used, an observation device (1) according to the present disclosure includes a light source part (11) in which a plurality of light emitting diodes (101) having different light emission wavelengths with a length of each light emission point being smaller than 100λ (λ: light emission wavelength) are arranged such that a separation distance between the adjacent light emitting diodes is equal to or smaller than 100λ (λ: light emission wavelength); and an image sensor (13) installed so as to be opposed to the light source part with respect to an observation target object.