Beam splitter/combiner and projection apparatus

A projection apparatus comprising a light source module, a beam splitter/combiner, a light valve, and a projection lens, wherein:

• the light source module is configured to generate a first color beam and a second color beam;
• the beam splitter/combiner is disposed on a transmission path of the first color beam and the second color beam, the beam splitter/combiner is configured to form an illumination beam from the first color beam and the second color beam, and the beam splitter/combiner comprises a first light-transmitting substrate, a first light transmission element, and a second light transmission element, wherein:
• the first light-transmitting substrate has a first optical surface facing incident light and a second optical surface opposite to the first optical surface;
• the first light transmission element is disposed on the first optical surface;
• the second light transmission element is disposed on the second optical surface;
• wherein the first color beam incident on the first light transmission element is reflected by the first light transmission element and leaves the first light transmission element, and the second color beam incident on the first light transmission element passes through the first light transmission element and the first light-transmitting substrate, is reflected by the second light transmission element, then passes through the first light-transmitting substrate and the first light transmission element, and leaves the first light transmission element,
• when a distance between the first color beam and the second color beam is d1, refractive index of the first light-transmitting substrate is n1, and an angle between the first color beam and a normal line of the first optical surface is θ, then a thickness of the and first light-transmitting substrate is t,
• t
• =
• n
• ⁢
• 1
• 2
• -
• sin
• 2
• ⁢
• θ
• sin
• ⁢
• 2
• ⁢
• θ
• ×
• d
• ⁢
• 1
• ,
• and
• wherein paths of the first color beam and the second color beam incident on or leaving the first light-transmitting substrate coincide;
• the light valve is disposed on a transmission path of the illumination beam, and the light valve is configured to convert the illumination beam into an image beam;
• and
• the projection lens is disposed on a transmission path of the image beam for projecting the image beam outside the projection apparatus.

A beam splitter/combiner comprising a first light-transmitting substrate, a first light transmission element, and a second light transmission element, wherein

• the first light-transmitting substrate has a first optical surface facing incident light and a second optical surface opposite to the first optical surface;
• the first light transmission element is disposed on the first optical surface;
• and
• the second light transmission element is disposed on the second optical surface, wherein a gas layer is located between the second light transmission element and the first light-transmitting substrate;
• wherein a first color beam incident on the first light transmission element is reflected by the first light transmission element and leaves the first light transmission element, and a second color beam incident on the first light transmission element passes through the first light transmission element and the first light-transmitting substrate, is reflected by the second light transmission element, then passes through the first light-transmitting substrate and the first light transmission element, and leaves the first light transmission element, and
• wherein paths of the first color beam and the second color beam incident on or leaving the first light-transmitting substrate coincide.

A beam splitter/combiner comprising a first light-transmitting substrate, a first light transmission element, and a second light transmission element, wherein

• the first light-transmitting substrate has a first optical surface facing incident light and a second optical surface opposite to the first optical surface;
• the first light transmission element is disposed on the first optical surface;
• and
• the second light transmission element is disposed on the second optical surface;
• wherein a first color beam incident on the first light transmission element is reflected by the first light transmission element and leaves th first light transmission element, and a second color beam incident on the first light transmission element passes through the first light transmission element and the first light-transmitting substrate, is reflected by the second light transmission element, then passes through the first light-transmitting substrate and the first light transmission element, and leaves the first light transmission element,
• wherein paths of the first color beam and the second color beam incident on or leaving the first light-transmitting substrate coincide, and
• wherein a relative angle between the second light transmission element and the second optical surface may be regulated, and the relative angle is-1 degree to 1 degree.

A beam splitter/combiner comprising a first light-transmitting substrate, a first light transmission element, a second light transmission element, and a third light transmission element, wherein

• the first light-transmitting substrate has a first optical surface facing incident light and a second optical surface opposite to the first optical surface;
• the first light transmission element is disposed on the first optical surface;
• and
• the second light transmission element is disposed on the second optical surface;
• wherein a first color beam incident on the first light transmission element is reflected by the first light transmission element and leaves the first light transmission element, and a second color beam incident on the first light transmission element passes through the first light transmission element and the first light-transmitting substrate, is reflected by the second light transmission element, then passes through the first light-transmitting substrate and the first light transmission element, and leaves the first light transmission element,
• wherein a gas layer is located between the third light transmission element and the second light transmission element;
• wherein a third color beam incident on the first light-transmitting substrate passes through the first light transmission element, the second light transmission element, and the gas layer, is reflected by the third light transmission element, passes through the gas layer, the second light transmission element, and the first light transmission element sequentially, and leaves the first light-transmitting substrate, and
• wherein paths of the first color beam, the second color beam, and the third color beam incident on or leaving the first light-transmitting substrate coincide.

A projection apparatus comprising a light source module, a beam splitter/combiner, a light valve, and a projection lens, wherein:

• the light source module is configured to generate a first color beam and a second color beam, wherein the light source module has at least two first color light units and at least one second color unit, a number of the at least two first color units is greater than a number of the at least one second color light unit, the at least two first color units are combined to emit the first color beam, and the at least one second color unit is combined to emit the second color beam;
• the beam splitter/combiner is disposed on a transmission path of the first color beam and the second color beam, the beam splitter/combiner is configured to form an illumination beam from the first color beam and the second color beam, and the beam splitter/combiner comprises a first light-transmitting substrate, a first light transmission element, and a second light transmission element, wherein:
• the first light-transmitting substrate has a first optical surface facing incident light and a second optical surface opposite to the first optical surface;
• the first light transmission element is disposed on the first optical surface;
• the second light transmission element is disposed on the second optical surface;
• wherein the first color beam incident on the first light transmission element is reflected by the first light transmission element and leaves the first light transmission element, and the second color beam incident on the first light transmission element passes through the first light transmission element and the first light-transmitting substrate, is reflected by the second light transmission element, then passes through the first light-transmitting substrate and the first light transmission element, and leaves the first light transmission element,
• wherein paths of the first color beam and the second color beam incident on or leaving the first light-transmitting substrate coincide, wherein when incident positions of the first color beam and the second color beam on a surface of the first light transmission element are different, emission positions of the first color beam and the second color beam leaving the surface of the first light transmission element are coincide, or when the incident positions of the first color beam and the second color beam incident on the surface of the first light transmission element are coincide, the emission positions of the first color beam and the second color beam leaving the surface of the first light transmission element are different;
• the light valve is disposed on a transmission path of the illumination beam, and the light valve is configured to convert the illumination beam into an image beam;
• and
• the projection lens is disposed on a transmission path of the image beam for projecting the image beam outside the projection apparatus.