Image projecting device and method

An image projecting device comprising a light source system, a spatial light modulator (SLM) unit, and an image projection optics accommodated at the output side of the SLM unit, wherein

• the light source system comprises n light sources and a light converting means to thereby produce m light beams of different wavelength ranges, wherein m>n, the device being configured for projecting a colored image, and having one of the following configurations:
• (a) comprises a wavelength-selective periscope structure allowing transparency for given wavelengths and reflecting other wavelengths, accommodated between the light source system and the SLM unit;
• (b) comprises additional SLM units, each in the optical path of the corresponding one of said light beams, and a wavelength combiner accommodated in the optical paths of modulated light beams emerging from the SLM units;
• the light source system has one of the following configurations:
• (a) comprises a laser diode emitting a light beam of the non-visible range, said light converting means comprising a splitter assembly for splitting said emitted light beam into at least two spatially separated light components, at least two crystals accommodated so as to be pumped by said at least two light components to produce two light beams, respectively, of different wavelengths and different from those of the pumping light components, and an assembly operable apply harmonic generation to said two light beams, to thereby produce two light outputs of different wavelengths in the visible range;
• (b) comprises a laser diode emitting a light beam including at least two light components of different wavelengths within the non-visible range, said light converting means comprising a splitter assembly for spatially separating said at least two light components of the emitted light beam and an assembly operable to apply second harmonic generation to said at least two light components, to thereby produce at least two light outputs of different wavelengths in the visible range;
• the SLM unit has one of the following configurations:
• (i) includes a pixel array arrangement in the form of a multi-layer structure defining a pixel array assembly and at least one microlens assembly enclosed between two substrates, the microlens assembly being located within a multi-layer polymer spacer structure between the substrate and the pixel assembly and including at least one microlens array accommodated proximate of the pixel array assembly at least upstream thereof with respect to a direction of propagation of light from the light source system towards the SLM unit, and operating to condense and focus incident light onto the pixel array;
• and (ii) includes a pixel array assembly and a microlens assembly, the microlens assembly having first and second microlens arrays accommodated in a spaced-apart parallel relationship at least upstream of the pixel array assembly with respect to a direction of propagation of light from the light source system towards the SLM unit and being located within a multi-layer polymer spacer structure between the respective substrate and the pixel assembly, the lenses of said second array located closer to the pixel array assembly being smaller or having different focal length than those of the first array, the lenslet assembly thereby condensing and focusing the incident light to impinge in form of a plurality of parallel light components onto a plurality of pixels, respectively.

A method for projecting a colored image, the method comprising:

• producing several incident light beams of several different wavelength ranges, at least one of the incident beams having a predetermined cross section corresponding to a size of an active surface of a spatial light modulator (SLM) unit defined by its pixel array assembly, and passing these incident light beams, on their ways to the SLM pixel arrangement, through a wavelength-selective periscope structure allowing transparency for given wavelengths and reflecting other wavelengths;
• operating the pixel assembly with an imaging signal representative of an image to be projected, thereby causing modulation of the light passing through the pixel assembly;
• passing the modulated light through an image projecting optics to a projecting surface;
• the method further comprising carrying out one of the following:
• (a) passing said incident light beams, while propagating towards the pixel array assembly inside the SLM unit, and the modulated light, while propagating from the pixel array assembly inside the SLM unit, through at least one microlens array that condenses and focuses a plurality of light components of the incident light to the centers of a plurality of said pixels, respectively, and converts the condensed beams of the modulated light the pixel array assembly into substantially parallel beams, said at least one microlens assembly being located within a pixel array assembly of the SLM unit such that said at least one microlens assembly is made in a polymer spacer between the pixel assembly and a glass substrate of the SLM unit;
• (b) said incident light beam, propagating towards the pixel array assembly, passes through first and second microlens arrays accommodated in a spaced-apart parallel relationship being made in a polymer spacer between the pixel assembly and a glass substrate of the SLM unit, wherein the lenses of said second array located closer to the pixel array assembly are smaller or have different focal length than those of the first array, the incident light being thereby condensed and focused to impinge onto a plurality of pixels in form of a plurality of parallel light components, respectively.

A method for projecting a colored image, the method comprising:

• producing several incident light beams of several different wavelength ranges, at least one of the incident beams having a predetermined cross section corresponding to a size of an active surface of a spatial light modulator (SLM) unit defined by its pixel array assembly, passing these light beams through the SLM units, respectively, and passing the modulated light beams through a wavelength combiner;
• operating the pixel assembly with an imaging signal representative of an image to be projected, thereby causing modulation of the light passing through the pixel assembly;
• passing the modulated light through an image projecting optics to a projecting surface;
• the method further comprising carrying out one of the following:
• (a) passing said incident light beams, while propagating towards the pixel array assembly inside the SLM unit, and the modulated light, while propagating from the pixel array assembly inside the SLM unit, through at least one microlens array that condenses and focuses a plurality of light components of the incident light to the centers of a plurality of said pixels, respectively, and converts the condensed beams of the modulated light the pixel array assembly into substantially parallel beams, said at least one microlens assembly being located within a pixel array assembly of the SLM unit such that said at least one microlens assembly is made in a polymer spacer between the pixel assembly and a glass substrate of the SLM unit;
• (b) said incident light beam, propagating towards the pixel array assembly, passes through first and second microlens arrays accommodated in a spaced-apart parallel relationship being made in a polymer spacer between the pixel assembly and a glass substrate of the SLM unit, wherein the lenses of said second array located closer to the pixel array assembly are smaller or have different focal length than those of the first array, the incident light being thereby condensed and focused to impinge onto a plurality of pixels in form of a plurality of parallel light components, respectively.

A method for projecting an image comprising:

• creating m light beams of different wavelength ranges by a light source system including n light sources and a light converting means in optical path of light generated by the n light sources, wherein m>n, said creating comprising emitting a light beam of the non-visible range, and converting said light beam into at least two light beams of different wavelengths in the visible range, at least one of said m light beams having a predetermined cross section corresponding to a size of an active surface of a spatial light modulator (SLM) unit defined by its pixel array assembly, and directing the incident light towards the pixel array assembly;
• operating the pixel assembly with an imaging signal representative of an image to be projected, thereby causing modulation of the light passing through the pixel assembly;
• passing the modulated light through an image projecting optics to a projecting surface;
• the method further comprising carrying out one of the following:
• (a) passing said incident light beam, while propagating towards the pixel array assembly inside the SLM unit, and the modulated light, while propagating from the pixel array assembly inside the SLM unit, through at least one microlens array that condenses and focuses a plurality of light components of the incident light to the centers of a plurality of said pixels, respectively, and converts the condensed beams of the modulated light the pixel array assembly into substantially parallel beams, said at least one microlens assembly being located within a pixel array assembly of the SLM unit such that said at least one microlens assembly is made in a polymer spacer between the pixel assembly and a glass substrate of the SLM unit;
• (b) said incident light beam, propagating towards the pixel array assembly, passes through first and second microlens arrays accommodated in a spaced-apart parallel relationship being made in a polymer spacer between the pixel assembly and a glass substrate of the SLM unit, wherein the lenses of said second array located closer to the pixel array assembly are smaller or have different focal length than those of the first array, the incident light being thereby condensed and focused to impinge onto a plurality of pixels in form of a plurality of parallel light components, respectively.

An image projecting device comprising a light source system, a spatial light modulator (SLM) unit, and an image projection optics accommodated at the output side of the SLM unit, wherein

• the light source system comprises at least one highly polarized light source and a randomly polarized light source;
• and
• the SLM unit has one of the following configurations:
• (i) said SLM unit includes a pixel array arrangement in the form of a multi-layer structure defining a pixel array assembly and at least one microlens assembly enclosed between two substrates, the microlens assembly being located within a multi-layer polymer spacer structure between the substrate and the pixel assembly and including at least one microlens array accommodated proximate of the pixel array assembly at least upstream thereof with respect to a direction of propagation of light from the light source system towards the SLM unit, and operating to condense and focus incident light onto the pixel array;
• (ii) said SLM unit includes a pixel array assembly and a microlens assembly, the microlens assembly having first and second microlens arrays accommodated in a spaced-apart parallel relationship at least upstream of the pixel array assembly with respect to a direction of propagation of light from the light source system towards the SLM unit and being located within a multi-layer polymer spacer structure between the respective substrate and the pixel assembly, the lenses of said second array located closer to the pixel array assembly being smaller or having different focal length than those of the first array, the lenslet assembly thereby condensing and focusing the incident light to impinge in form of a plurality of parallel light components onto a plurality of pixels, respectively.

An image projecting device comprising a light source system including at least one high-ratio polarized light source, a spatial light modulator (SLM) unit, and an image projection optics accommodated at the output side of the SLM unit, the device being characterized in that said SLM unit is of a reflective type and comprises a polarization beam splitter/combiner, the device having at least one of the following configurations:

• (i) said SLM unit includes a pixel array arrangement in the form of a multi-layer structure defining a pixel array assembly and at least one microlens assembly enclosed between two substrates, the microlens assembly including at least one microlens array accommodated proximate of the pixel array assembly at least upstream thereof with respect to a direction of propagation of light from the light source system towards the SLM unit, and operating to condense and focus incident light onto the pixel array;
• (ii) said SLM unit including a pixel array assembly and a microlens assembly, the microlens assembly having first and second microlens arrays accommodated in a spaced-apart parallel relationship at least upstream of the pixel array assembly with respect to a direction of propagation of light from the light source system towards the SLM unit, the lenses of said second array located closer to the pixel array assembly being smaller or having different focal length than those of the first array, the lenslet assembly thereby condensing and focusing the incident light to impinge in form of a plurality of parallel light components onto a plurality of pixels, respectively;
• (iii) the light source system comprises n light sources and a light converting means in optical path of light generated by the n light sources to thereby produce m light beams of different wavelength ranges, wherein m>n;
• (iv) the light source system comprises a multi-mode laser, thereby reducing a speckle effect in an integrated speckle pattern produced by the multiple modes, as compared to that of a single mode;
• (v) the light source system comprises at least one highly polarized light source and a randomly polarized light source.

A method for projecting a colored image, the method comprising creating incident light beams of different wavelength ranges by at least one-highly polarized light source and a randomly-polarized light source, at least one of the incident light beams having a predetermined cross section corresponding to a size of an active surface of a spatial light modulator (SLM) unit defined by its pixel array assembly, and directing the incident light towards the pixel array assembly;

• operating the pixel assembly with an imaging signal representative of an image to be projected, thereby causing modulation of the light passing through the pixel assembly;
• passing the modulated light through an image projecting optics to a projecting surface;
• the method further comprising carrying out one of the following:
• (a) passing said incident light beam, while propagating towards the pixel array assembly inside the SLM unit, and the modulated light, while propagating from the pixel array assembly inside the SLM unit, through at least one microlens array that condenses and focuses a plurality of light components of the incident light to the centers of a plurality of said pixels, respectively, and converts the condensed beams of the modulated light the pixel array assembly into substantially parallel beams, said at least one microlens assembly being located within a pixel array assembly of the SLM unit such that said at least one microlens assembly is made in a polymer spacer between the pixel assembly and a glass substrate of the SLM unit;
• (b) said incident light beam, propagating towards the pixel array assembly, passes through first and second microlens arrays accommodated in a spaced-apart parallel relationship being made in a polymer spacer between the pixel assembly and a glass substrate of the SLM unit, wherein the lenses of said second array located closer to the pixel array assembly are smaller or have different focal length than those of the first array, the incident light being thereby condensed and focused to impinge onto a plurality of pixels in form of a plurality of parallel light components, respectively.

A method for projecting a colored image, the method comprising:

• creating incident light beams of different wavelength ranges by at least one-highly polarized light source and a randomly-polarized light source, at least one of the incident light beams having a predetermined cross section corresponding to a size of an active surface of a reflective spatial light modulator (SLM) unit defined by its pixel array assembly, and directing the incident light towards the pixel array assembly;
• operating the pixel assembly with an imaging signal representative of an image to be projected, thereby causing modulation of the light passing through the pixel assembly;
• passing the modulated light through an image projecting optics to a projecting surface;
• the method comprising passing the incident light beam propagating towards the pixel array assembly and the reflected modulated light emerging from the pixel array assembly, through a polarization beam splitter, the method further comprising carrying out at least one of the following,
• (a) passing said incident light beam, while propagating towards the pixel array assembly inside the SLM unit, and the modulated light, while propagating from the pixel array assembly inside the SLM unit, through at least one microlens array that condenses and focuses a plurality of light components of the incident light to the centers of a plurality of said pixels, respectively, and converts the condensed beams of the modulated light the pixel array assembly into substantially parallel beams;
• (b) said incident light beam, propagating towards the pixel array assembly, passes through first and second microlens arrays accommodated in a spaced-apart parallel relationship, wherein the lenses of said second array located closer to the pixel array assembly are smaller or have different focal length than those of the first array, the incident light being thereby condensed and focused to impinge onto a plurality of pixels in form of a plurality of parallel light components, respectively.

A method for projecting a colored image, the method comprising:

• creating incident light beams of different wavelength ranges by at least one-highly polarized light source and a randomly-polarized light source, at least one of the incident light beams having a predetermined cross section corresponding to a size of an active surface of a spatial light modulator (SLM) unit defined by its pixel array assembly, and directing the incident light towards the pixel array assembly;
• operating the pixel assembly with an imaging signal representative of an image to be projected, thereby causing modulation of the light passing through the pixel assembly;
• passing the modulated light through an image projecting optics to a projecting surface;
• the method comprising providing specific polarization of the incident light, and passing the modulated light emerging from the SLM pixel arrangement through a polarizer having a preferred orientation of a plane of polarization so as to be either substantially the same as of the incident light beam or a 90-degree rotated with respect to that of the incident light beam, the method further comprising carrying out at least one of the following:
• (a) passing said incident light beam, while propagating towards the pixel array assembly inside the SLM unit, and the modulated light, while propagating from the pixel array assembly inside the SLM unit, through at least one microlens array that condenses and focuses a plurality of light components of the incident light to the centers of a plurality of said pixels, respectively, and converts the condensed beams of the modulated light the pixel array assembly into substantially parallel beams;
• (b) said incident light beam, propagating towards the pixel array assembly, passes through first and second microlens arrays accommodated in a spaced-apart parallel relationship, wherein the lenses of said second array located closer to the pixel array assembly are smaller or have different focal length than those of the first array, the incident light being thereby condensed and focused to impinge onto a plurality of pixels in form of a plurality of parallel light components, respectively.

A method for projecting an image comprising:

• creating at least one incident light beam having a predetermined cross section corresponding to a size of an active surface of a spatial light modulator (SLM) unit defined by its pixel array assembly, and directing the incident light towards the pixel array assembly;
• operating the pixel assembly with an imaging signal representative of an image to be projected, thereby causing modulation of the light passing through the pixel assembly;
• passing the modulated light through an image projecting optics to a projecting surface;
• the method comprising creating m light beams of different wavelength ranges by a light source system including n light sources and a light converting means in optical path of light generated by the n light sources, wherein m>n, said producing of m light beams by n light sources comprising emitting a light beam of the non-visible range, and converting said light beam into at least two light beams of different wavelengths in the visible range, said converting comprising splitting said emitted light beam into at least two spatially separated light components for pumping at least two laser crystals, respectively, to thereby produce two light beams, respectively, of different wavelengths and different from those of the pumping light components, and applying harmonic generation to said two light beams to produce two light outputs of different wavelengths in the visible range.

A method for projecting an image comprising:

• creating at least one incident light beam having a predetermined cross section corresponding to a size of an active surface of a transmissive spatial light modulator (SLM) unit defined by its pixel array assembly, and directing the incident light towards the pixel array assembly;
• operating the pixel assembly with an imaging signal representative of an image to be projected, thereby causing modulation of the light passing through the pixel assembly;
• passing the modulated light through an image projecting optics to a projecting surface, the method comprising:
• passing said incident light beam, while propagating towards the pixel array assembly inside the SLM unit, and the modulated light, while propagating from the pixel array assembly inside the SLM unit, through at least one first microlens array and at least one second microlens array at opposite sides of the pixel array assembly, respectively, such that each lens in the first array is associated with a corresponding pixel of the pixel array and with the corresponding lens in the second array, each lens being substantially of the pixel size, the microlens arrays condensing and focusing a plurality of light components of the incident light to the centers of a plurality of said pixels, respectively, and converting the condensed beams of the modulated light from the pixel array assembly into substantially parallel beams.