Abstract: In an optical system that includes a coherent light source and an optical waveguide, a pulse width used by the optical waveguide to project image frames on a display is changed on a frame-by-frame basis. By changing the pulse width for each image frame, the locations and characteristics of visible interference patterns on the display are changed for each successive image frame. Changing the interference patterns for each image frame may result in the interference patterns being less detectable to a viewer. The change in pulse width for each image frame may be fixed or dynamic, and may be made in response to interference patterns being detected on the display.

Abstract: In an optical system that includes a coherent light source and an optical waveguide, a pulse width used by the optical waveguide to project image frames on a display is changed on a frame-by-frame basis. By changing the pulse width for each image frame, the locations and characteristics of visible interference patterns on the display are changed for each successive image frame. Changing the interference patterns for each image frame may result in the interference patterns being less detectable to a viewer. The change in pulse width for each image frame may be fixed or dynamic, and may be made in response to interference patterns being detected on the display.

Abstract: A coating method that improves uniformity of coatings that settle on more complex objects, like porous substrates, or substrates with hollows or curvy forms, and a device for implementing the method. The coating device includes a deposition chamber, and a loading structure configured to load an object into a position in the deposition chamber and unload the object from the deposition chamber. The coating device includes an atomization element in a bottom part of the deposition chamber, the atomization element creating into the deposition chamber an aerosol volume that includes a floating aerosol region in the top part of the deposition chamber. The loading structure is configured to load the object into a position in the floating aerosol region in the deposition chamber.

Abstract: A multi-component coating apparatus that includes at least two deposition chambers. Aerosol in the chambers is adjusted to a to a non-impact state in which particles of the aerosol settle onto surfaces exposed to the aerosol a limited interaction period. The surface to be coated is transferred from the first chambers to the second chamber in a predefined period during which chemical interaction between the first substance and the second substance is enabled. The arrangement is very simple and robust, so also larger scale objects, for example in the order of vehicle or machinery components may be coated with very thin films.

Abstract: The present invention relates to an apparatus and method for producing aerosol. The apparatus comprising a first atomizer for producing a first aerosol jet and a second atomizer for producing a second aerosol jet, each atomizer comprising an atomizing head in which the liquid is atomized into an atomized aerosol jet. Said atomizers further comprise a focusing part arranged to restrain the atomized aerosol jet for providing a punctual aerosol jet, said focusing part extending directly from the atomizing head. The first and second atomizer form an atomizer pair such that the atomizers are aligned towards each other for colliding the aerosol jets to each other.

Abstract: A burner nozzle is disclosed, comprising a nozzle body that includes a slit such that a line passage to the slit opens in an outlet face surface at the surface of the burner nozzle body. A plurality of channels is connected to the slit. A group of first channels is connected to a source of oxidizing substance, and a group of second channels is connected to a fuel source. Each of the first channels and second channels have a circumferential passage to the slit at a non-zero distance from the outlet face surface. Furthermore, each of the first channels and second channels is formed to output a directed tubular flow towards a side wall of the slit, or towards a circumferential passage in a side wall of the slit. A safe pre-mixed burner configuration is achieved. A burner and a surface treatment device incorporating the burner nozzle are also disclosed.

Abstract: The invention relates to a method of coating a substrate in a deposition chamber. The method comprising the steps of providing a source of at least one liquid precursor; atomizing the at least one liquid precursor into liquid droplets in the deposition chamber for producing aerosol; filling the deposition chamber with aerosol for forming saturated aerosol in the deposition chamber; and settling saturated aerosol by gravitation towards a surface of the substrate for coating the substrate in the deposition chamber.

Abstract: The present invention relates to an apparatus and method for producing aerosol. The apparatus comprising a first atomizer for producing a first aerosol jet and a second atomizer for producing a second aerosol jet, each atomizer comprising an atomizing head in which the liquid is atomized into an atomized aerosol jet. Said atomizers further comprise a focusing part arranged to restrain the atomized aerosol jet for providing a punctual aerosol jet, said focusing part extending directly from the atomizing head. The first and second atomizer form an atomizer pair such that the atomizers are aligned towards each other for colliding the aerosol jets to each other.

Abstract: A burner nozzle is disclosed, comprising a nozzle body that includes a slit such that a line passage to the slit opens in an outlet face surface at the surface of the burner nozzle body. A plurality of channels is connected to the slit. A group of first channels is connected to a source of oxidizing substance, and a group of second channels is connected to a fuel source. Each of the first channels and second channels have a circumferential passage to the slit at a non-zero distance from the outlet face surface. Furthermore, each of the first channels and second channels is formed to output a directed tubular flow towards a side wall of the slit, or towards a circumferential passage in a side wall of the slit. A safe pre-mixed burner configuration is achieved. A burner and a surface treatment device incorporating the burner nozzle are also disclosed.

Abstract: An optical waveguide including a core, a buffer surrounding the core, and a cladding surrounding the buffer. The core, the buffer and the cladding include silica glass. A refractive index of the buffer is substantially equal to a refractive index of pure amorphous silica glass. The buffer may reduce bubble formation during manufacturing and may facilitate splicing of the waveguide. A numerical aperture of the waveguide may be fine-tuned by adjusting a radial dimension of the buffer in order to compensate variations in the refractive index of the core.

Abstract: The invention relates to a bundle of optical fibers and a process for its preparation, wherein at least two of the optical fibers are at least partly attached to each other lengthwise by means of a removable longitudinal bridging element. Typically, the bridging element is an open one-hole capillary.

Abstract: An optical waveguide including a core, a buffer surrounding the core, and a cladding surrounding the buffer. The core, the buffer and the cladding include silica glass. A refractive index of the buffer is substantially equal to a refractive index of pure amorphous silica glass. The buffer may reduce bubble formation during manufacturing and may facilitate splicing of the waveguide. A numerical aperture of the waveguide may be fine-tuned by adjusting a radial dimension of the buffer in order to compensate variations in the refractive index of the core.

Abstract: A method and a liquid feeding device for feeding liquid in a flame spraying apparatus that is arranged for treating an optical fiber structure, as well as a flame spraying apparatus in which liquid feeding is arranged according to the invention. Liquid is supplied to an unpressurized space in a pressure generating part substantially in a constant flow. In the pressure generating part the pressure of liquid is generated by means of gravity influencing the liquid, and the pressurized liquid is arranged to be supplied to the flame spraying at a substantially constant pressure and at a constant flow rate.

Abstract: A light-amplifying fiber arrangement including a pump fiber including glass and a bridge element. At least a portion of a side of the bridge element has been fused to at least a portion of a side of the pump fiber. An active fiber includes a light-amplifying core and a first cladding. The first cladding includes glass. At least a portion of a side of the active element has been fused to at least a portion of a side of the bridge element. A second cladding surrounds the pump and active fibers in order to confine pump light to the fibers. The second cladding includes glass. The arrangement allows coupling of high power levels into the pump fiber, wherein splicing of pigtails to the arrangement is easier than e.g. in case of conventional doubly clad fibers.

Abstract: The invention relates to a process of preparing an optical fiber joint, wherein an optical fiber or its undrawn precursor is brought into contact with a longitudinal element and attached to it via a ridge-groove fitting prior to drawing of the final optical fiber joint. The longitudinal element can be another optical fiber or its precursor or a removable and/or workable bridging element.

Abstract: A light-amplifying fiber arrangement including a pump fiber including glass and a bridge element. At least a portion of a side of the bridge element has been fused to at least a portion of a side of the pump fiber. An active fiber includes a light-amplifying core and a first cladding. The first cladding includes glass. At least a portion of a side of the active element has been fused to at least a portion of a side of the bridge element. A second cladding surrounds the pump and active fibers in order to confine pump light to the fibers. The second cladding includes glass. The arrangement allows coupling of high power levels into the pump fiber, wherein splicing of pigtails to the arrangement is easier than e.g. in case of conventional doubly clad fibers.

Abstract: The invention relates to a bundle of optical fibers and a process for its preparation, wherein at least two of the optical fibers are at least partly attached to each other lengthwise by means of a removable longitudinal bridging element. Typically, the bridging element is an open one-hole capillary.

Abstract: A method and a device in optical fiber based spectral filtering. A length of an optical fiber including at least a core region surrounded by a cladding region is coiled over its length in whole or in part to subject the fiber to longitudinal curvature in order to affect the optical transmission properties of the fiber. The fiber is arranged to have radially asymmetric refractive index distribution and in addition to coiling the fiber lengthwise, the fiber is over its length in whole or in part also twisted around its longitudinal axis. The method and device can be used to significantly improve the performance of fiber based filtering devices.

Abstract: This invention relates to detecting a pilot tone in an optical fiber. In the method described in the invention, computational complexity is reduced significantly by almost completely removing the need to carry out multipli-cations. To calculate certain spectral components of DFT (Discrete Fourier Transform) only a few multiplications are required. The idea is that for de-tecting one pilot tone, it is adequate to calculate one spectral component of DFT if a specific ratio can be chosen between the pilot tone frequency and the sample rate of the receiver.

Abstract: The invention relates to a process of preparing an optical fiber joint, wherein an optical fiber or its undrawn precursor is brought into contact with a longitudinal element and attached to it via a ridge-groove fitting prior to drawing of the final optical fiber joint. The longitudinal element can be another optical fiber or its precursor or a removable and/or workable bridging element.