LIGHT SOURCE MODULE

A light source module includes a light guide plate, a first light source, multiple first optical microstructures, and multiple second optical microstructures. The first light source is disposed on a side of a first light incident surface of the light guide plate. The first and second optical microstructures are disposed on a bottom surface of the light guide plate, and respectively located in a first and a second zone. A first light receiving surface of each first optical microstructure facing the first light source has a first edge connecting the bottom surface, and a perpendicular bisector of the first edge passes through the first light source. The first zone does not overlap the second zone. A second light receiving surface of each second optical microstructure has a second edge connecting the bottom surface, and a perpendicular bisector of the second edge does not pass through the first light source.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority benefit of China application serial no. 202311111239.1, filed on Aug. 31, 2023. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.

BACKGROUND

Technical Field

The disclosure relates to a light source module, and in particular, to a light source module with a display function.

Related Art

With the advancement of lighting technology, in addition to lighting devices that are generally used to provide lighting functions, decorative lighting panels (light source module) that provide decorative effects have also been developed on the market. In this kind of decorative lighting panel, optical microstructures are formed on the bottom surface of the light guide plate, and the position of each optical microstructure and the angle of its reflective surface are configured according to the effect that the decorative lighting panel needs to present. After being incident from the side surface (light incident surface) of the light guide plate, the light emitted by the light source may be transmitted toward the light emitting surface of the light guide plate through reflection by the optical microstructure and emits light, allowing the user to see patterns or text formed by the light on the side of the light emitting surface of the light guide plate.

In recent years, in order to improve the visual experience of viewers, the demand for using decorative lighting panels to present more vivid images has gradually increased. In order to increase the dynamic effect of the image, the number of light sources may be increased or addressable or programmable light sources may be selected. However, these methods not only increase production costs, but also the driver circuit boards used in general decorative lighting panel products cannot be directly applied to such decorative lighting panel products with dynamic effects.

SUMMARY

An embodiment of the disclosure provides a light source module. The light source module includes a light guide plate, a first light source, a plurality of first optical microstructures, and a plurality of second optical microstructures. The light guide plate has a first light incident surface and a bottom surface connected to the first light incident surface. The first light source is disposed on one side of the first light incident surface of the light guide plate. The first optical microstructures are disposed on the bottom surface of the light guide plate and located in a first zone of the bottom surface. Each of the first optical microstructures has a first light receiving surface disposed toward the first light source. Each of the first light receiving surfaces has a first edge connecting the bottom surface, and a perpendicular bisector of the first edge passes through the first light source. The second optical microstructures are disposed on the bottom surface of the light guide plate and located in a second zone of the bottom surface. The first zone does not overlap the second zone. Each of the second optical microstructures has a second light receiving surface. Each of the second light receiving surfaces has a second edge connecting the bottom surface, and a perpendicular bisector of the second edge does not pass through the first light source.

To make the above features and advantages of the disclosure clearer and easier to understand, embodiments will be specifically provided below and described in detain with reference to the accompanying drawings.

DESCRIPTION OF THE EMBODIMENTS

The disclosure provides a light source module, which has better dynamic effect of presenting images and has cost advantages.

FIG.1is a schematic front view of a light source module according to the first embodiment of the disclosure.FIG.2Ais a schematic side view of the light source module ofFIG.1.FIG.2Bis a schematic cross-sectional view of the light source module ofFIG.1.FIG.3is a schematic diagram of the distribution of normalized brightness versus viewing angle after light is reflected by the optical microstructures in different zones ofFIG.1.FIGS.4A to4Care schematic diagrams of images presented by the light source module ofFIG.1in three viewing angle directions parallel to the light incident surface of the light guide plate.

Please refer toFIG.1,FIG.2A, andFIG.2B. A light source module10includes a light guide plate100, a first light source121, and a plurality of optical microstructures. The light guide plate100has a first light incident surface100is1, a light emitting surface100es,and a bottom surface100bs.The light emitting surface100esand the bottom surface100bsare opposite to each other, and both are connected to the first light incident surface100is1. The first light source121is disposed on one side of the first light incident surface100is1of the light guide plate100, the first light source121is, for example, a light-emitting diode or light-emitting element. The optical microstructures are disposed on the bottom surface100bsof the light guide plate100.

For example, in this embodiment, the bottom surface100bsof the light guide plate100may have a first zone Z1, a second zone Z2, and a third zone Z3. A plurality of optical microstructures MS1are provided in the first zone Z1. A plurality of optical microstructures MS2are provided in the second zone Z2. A plurality of optical microstructures MS3are provided in the third zone Z3.

It is particularly noted that these zones of the bottom surface100bsdo not overlap along the normal direction of the light emitting surface100es(for example, the axial direction of the Z axis). In other words, each of these zones is continuously distributed on the bottom surface100bs.From another point of view, one single (or a few) optical microstructure MS1, optical microstructure MS2, and optical microstructure MS3are not alternately arranged.

In this embodiment, the plurality of optical microstructures MS1located in the first zone Z1respectively has a light receiving surface rs1facing the first light source121. Each of the light receiving surfaces rs1has an edge e1connecting the bottom surface100bs.The plurality of optical microstructures MS2located in the second zone Z2respectively has a light receiving surface rs2. Each of the light receiving surfaces rs2has an edge e2connecting the bottom surface100bs.The plurality of optical microstructures MS3located in the third zone Z3respectively has a light receiving surface rs3. Each of the light receiving surfaces rs3has an edge e3connecting the bottom surface100bs.Specifically, in this embodiment, each of the optical microstructures is, for example, a concave triangular prism-shaped structure.

It is particularly noted that a perpendicular bisector PB1of the edge e1passes through the first light source121(for example, an orthographic projection of the perpendicular bisector PB1on a virtual extended surface of the bottom surface100bspasses through an orthographic projection area of the first light source121on a virtual extended surface of the bottom surface100bs,as shown inFIG.1. In the disclosure, similar contents are as described above and will not be repeated), but a perpendicular bisector PB2of the edge e2and a perpendicular bisector PB3of the edge e3do not pass through the first light source121. More specifically, in this embodiment, the perpendicular bisectors PB2of the plurality of optical microstructures MS2pass through the same side of the first light source121(for example, the upper side of the first light source121inFIG.1, but not limited thereto), and the perpendicular bisectors PB3of the plurality of optical microstructures MS3pass through the same other side of the first light source121(for example, the lower side of the first light source121inFIG.1, but not limited thereto).

For example, in this embodiment, the perpendicular bisector PB1of the edge e1of the light receiving surface rs1of each optical microstructure MS1passes through an emitting surface121esof the first light source121, for example, substantially through a geometric center GC1of the emitting surface121es(for example, the perpendicular bisector PB1has an intersection point with the emitting surface121es,and the offset between the intersection point and the geometric center GC1is not larger than 5% of the width of the emitting surface121esin the Y direction). In other words, the edge e1of each optical microstructure MS1is not necessarily parallel. On the other hand, there is a virtual connection line between a geometric center GC2of the optical microstructure MS2(for example, the geometric center of the orthographic projection area of the optical microstructure MS2on the bottom surface100bs) and the geometric center GC1of the first light source121. The perpendicular bisector PB2of the edge e2of the light receiving surface rs2of each optical microstructure MS2deflects clockwise by an angle θ1relative to the virtual connection line, and the angle θ1deflected varies with the relative positions of the optical microstructure MS2and the first light source121. There is also a virtual connection line between a geometric center GC3of the optical microstructure MS3and the geometric center GC1of the first light source121. The perpendicular bisector PB3of the edge e3of the light receiving surface rs3of each optical microstructure MS3deflects counter-clockwise by an angle θ2relative to the virtual connection line, and the angle θ2deflected varies with the relative positions of the optical microstructure MS3and the first light source121. The clockwise deflection or counter-clockwise deflection mentioned here is, for example, the rotation of the optical microstructure along an axis (not shown) that passes through its geometric center and is parallel to the Z axis. In one embodiment, as shown inFIG.1, the intersection point of the perpendicular bisector PB2of each optical microstructure MS2and an extended plane (not shown) of the emitting surface121esof the first light source121is located on one side of the first light source121, and its distance from the geometric center GC1of the first light source121is, for example, within the range of two to ten times (or two to five times) the width of the emitting surface121esof the first light source121in the Y direction. The intersection point of the perpendicular bisector PB3of each optical microstructure MS3and the extended plane of the emitting surface121esof the first light source121is located on the other side of the first light source121, and its distance from the geometric center GC1of the first light source121is, for example, within the range of two to ten times (or two to five times) the width of the emitting surface121esof the first light source121in the Y direction.

On the other hand, there is a base angle α1between the light receiving surface rs1of the optical microstructure MS1and the virtual extended surface of the bottom surface100bs(shown inFIG.2B). There is a base angle α2between the light receiving surface rs2of the optical microstructure MS2and the virtual extended surface of the bottom surface100bs.There is a base angle α3between the light receiving surface rs3of the optical microstructure MS3and the virtual extended surface of the bottom surface100bs.In this embodiment, the base angle α1of the optical microstructure MS1, the base angle α2of the optical microstructure MS2, and the base angle α3of the optical microstructure MS3are, for example, the same.

In this embodiment, the first light source121emits a first light L1, a second light L2, and a third light L3toward the optical microstructures MS1, the optical microstructures MS2, and the optical microstructures MS3respectively. The first light L1has a first main light emitting direction MED1after being reflected by the optical microstructures MS1. The second light L2has a second main light emitting direction MED2after being reflected by the optical microstructures MS2. The third light L3has a third main light emitting direction MED3after being reflected by the optical microstructures MS3.

It is particularly noted that the first main light emitting direction MED1of the first light L1reflected by the optical microstructure MS1, the second main light emitting direction MED2of the second light L2reflected by the optical microstructure MS2, and the third main light emitting directions MED3of the third light L3reflected by the optical microstructure MS3are different from each other, as shown inFIG.2A.

Further, in this embodiment, the first main light emitting direction MED1may be parallel to the Z axis (i.e., perpendicular to the X axis and the Y axis), where the X axis, the Y axis, and the Z axis are perpendicular to each other. That is, the first main light emitting direction MED1is perpendicular to the light emitting surface100esof the light guide plate100(i.e., an XY plane formed by the X axis and the Y axis).

However, neither the second main light emitting direction MED2nor the third main light emitting direction MED3is parallel to the Z axis. More specifically, an orthographic projection MED2yzof the second main light emitting direction MED2on a YZ plane (that is, the plane formed by the Y axis and the Z axis) has an axial component in the same direction as the Y axis (as shown inFIG.2A), and an orthographic projection MED3yzof the third main light emitting direction MED3on the YZ plane has an axial component in the opposite direction to the Y axis (as shown inFIG.2A).

From another point of view, there is an angle β1between the orthographic projection MED2yzof the second main light emitting direction MED2on the YZ plane and an orthographic projection MED1yzof the first main light emitting direction MED1on the YZ plane, and there is an angle β2between the orthographic projection MED3yzof the third main light emitting direction MED3on the YZ plane and the orthographic projection MED1yzof the first main light emitting direction MED1on the YZ plane. In this embodiment, the orthographic projection MED2yzand the orthographic projection MED3yzof the second main light emitting direction MED2and the third main light emitting direction MED3on the YZ plane may be respectively located on opposite sides of the orthographic projection MED1yzof the first main light emitting direction MED1on the YZ plane, and the angle β1and the angle β2may selectively be the same, but are not limited thereto.

In particular, since the base angle α1of the optical microstructure MS1, the base angle α2of the optical microstructure MS2, and the base angle α3of the optical microstructure MS3of this embodiment are all the same, the first main light emitting direction MED1, the second main light emitting direction MED2, and the third main light emitting direction MED3are all parallel to the first light incident surface100is1or the YZ plane of the light guide plate100. That is, an orthographic projection MED1xz,an orthographic projection MED2xz,and an orthographic projection MED3xzof the first main light emitting direction MED1, the second main light emitting direction MED2, and the third main light emitting direction MED3respectively on an XZ plane (i.e. the plane formed by the X axis and the Z axis) do not have axial components in the same direction as or opposite direction to the X axis.

That is, in this embodiment, the first main light emitting direction MED1, the second main light emitting direction MED2, and the third main light emitting direction MED3are not parallel to each other in the dimension of the YZ plane (as shown inFIG.2A), but are parallel to each other in the dimension of the XZ plane (as shown inFIG.2B).

In the dimension of the YZ plane, the distribution curves of the normalized brightness to viewing angle of each of the first light L1reflected by the optical microstructure MS1of the first zone Z1, the second light L2reflected by the optical microstructure MS2of the second zone Z2, and the third light L3reflected by the optical microstructure MS3of the third zone Z3are shown inFIG.3. As may be seen fromFIG.3, in this embodiment, the first main light emitting direction MED1of the first light L1is, for example, the direction of the viewing angle of 0 degrees; the second main light emitting direction MED2of the second light L2is, for example, the direction of the viewing angle of −10 degrees; and the third main light emitting direction MED3of the third light L3is, for example, the direction of the viewing angle of +10 degrees.

It is particularly noted that in the first main light emitting direction MED1(for example, viewed from the direction of a viewing angle of 0 degrees), the light emitting brightness of the first zone Z1is significantly higher than the light emitting brightness of the second zone Z2and the light emitting brightness of the third zone Z3, and the light emitting brightness of the second zone Z2is equivalent to the light emitting brightness of the third zone Z3. In the second main light emitting direction MED2, the light emitting brightness of the second zone Z2is significantly higher than the light emitting brightness of the first zone Z1and the light emitting brightness of the third zone Z3, and the light emitting brightness of the first zone Z1is higher than the light emitting brightness of the third zone Z3. In the third main light emitting direction MED3, the light emitting brightness of the third zone Z3is significantly higher than the light emitting brightness of the first zone Z1and the light emitting brightness of the second zone Z2, and the light emitting brightness of the first zone Z1is higher than the light emitting brightness of the second zone Z2. In this way, when the user views the light guide plate100in different directions, the user may see different brightness changes in different zones.

Please refer toFIG.4AtoFIG.4C. In this embodiment, the light guide plate100is, for example, a decorative lighting panel, and the orthographic projections of the first zone Z1, the second zone Z2and the third zone Z3provided with different optical microstructures on the light emitting surface100esmay form a decorative pattern, for example, the pattern shown inFIG.4Ais a house pattern (the content of the pattern is not particularly limited in the disclosure). The first zone Z1, the second zone Z2, and the third zone Z3are different zones (such as walls or roofs) that constitute the house pattern. In particular, the first zone Z1, the second zone Z2, and the third zone Z3described in the disclosure are not general decorative patterns that produce a flashing effect, thus, the size of each zone is relatively large. For example, the length of the first zone Z1(the second zone Z2) is at least one tenth or more of the length of the light guide plate100, and the width of the first zone Z1(the second zone Z2) is at least one tenth or more of the width of the light guide plate100. As shown inFIG.4A, when the user views the light guide plate100at a viewing angle of −10 degrees in the dimension of the YZ plane (for example, the upper viewing angle along the YZ plane inFIG.4B), the brightness of the second zone Z2is higher than the light emitting brightness of each of the first zone Z and the third zone Z3, and the light emitting brightness of the first zone Z1is higher than the light emitting brightness of the third zone Z3.

As shown inFIG.4B, when the user views the light guide plate100at a viewing angle of 0 degrees in the dimension of the YZ plane (for example, the front viewing angle along the YZ plane inFIG.4B), the brightness of the first zone Z1is higher than the light emitting brightness of each of the second zone Z2and the third zone Z3, and the light emitting brightness of the second zone Z2is equivalent to the light emitting brightness of the third zone Z3.

As shown inFIG.4C, when the user views the light guide plate100at a viewing angle of +10 degrees in the dimension of the YZ plane (for example, the lower viewing angle along the YZ plane inFIG.4B), the brightness of the third zone Z3is higher than the light emitting brightness of each of the second zone Z2and the first zone Z1, and the light emitting brightness of the first zone Z1is higher than the light emitting brightness of the second zone Z2.

That is to say, when the user views the decorative pattern formed by the first zone Z1, the second zone Z2, and the third zone Z3at different viewing angles in the dimension of the YZ plane, the brightness distribution of the decorative patterns varies with the change of viewing angle, which in turn produces a dynamic effect with light and shadow changes. In this way, the flat pattern can produce a three-dimensional visual effect when the user moves to view the light guide plate100. On the other hand, the light source module10of this embodiment achieves the dynamic effect of light emitting distribution by arranging optical microstructures in different ways in different zones of the light guide plate100, thus compared with the current method of increasing the number of light sources or selecting addressable light sources, the light source module10also have lower production costs.

Other embodiments will be enumerated below to describe the disclosure in detail, in which the same components will be given with the same symbols, and descriptions of the same technical content will be omitted. Please refer to the previous embodiments for the omitted parts, which will not be described again below.

FIG.5is a schematic front view of a light source module according to a second embodiment of the disclosure.FIG.6Ais a schematic side view of the light source module ofFIG.5.FIG.6Bis a schematic cross-sectional view of the light source module ofFIG.5.FIG.7A to7Care schematic diagrams of images presented by the light source module ofFIG.5in three viewing angle directions parallel to a plane perpendicular to the light incident surface and the light emitting surface of the light guide plate.

Please refer toFIG.5,FIG.6A, andFIG.6B. Different from the light guide plate100ofFIG.1andFIG.2, in a light source module10A of this embodiment, a base angle α1″ of a light receiving surface rs1-A of an optical microstructure MS1-A of a light guide plate100A may be selectively larger than a base angle α3″ of a light receiving surface rs3-A of an optical microstructure MS3-A, and may be selectively smaller than a base angle α2″ of a light receiving surface rs2-A of an optical microstructure MS2-A. In other embodiments, the relationship of angle sizes between the base angle α1″, the base angle α2″, and the base angle α3″ may also be adjusted according to the actual situation.

That is, the base angles of the optical microstructure MS1-A, the optical microstructure MS2-A, and the optical microstructure MS3-A of this embodiment are all different. Thus, a first light L1″, a second light L2″, and a third light L3″ respectively reflected through these optical microstructures are not parallel to each other in the dimension of the XZ plane, as shown inFIG.6B.

For example, in this embodiment, the orthographic projection MED1xzof a first main light emitting direction MED1-A of the first light L1″ on the XZ plane is parallel to the Z axis, and the orthographic projection MED2xzof a second main light emitting direction MED2-A of the second light L2″ on the XZ plane and the orthographic projection MED3xzof a third main light emitting direction MED3-A of the third light L3″ on the XZ plane are not parallel to the Z axis. More specifically, the orthographic projection MED2xzof the second main light emitting direction MED2-A on the XZ plane has an axial component in the opposite direction to the X axis (as shown inFIG.6B), and the orthographic projection MED3xzof the third main light emitting direction MED3-A on the XZ plane has an axial component in the same direction as the X axis (as shown inFIG.6B).

From another point of view, there is an angle β3between the orthographic projection MED2xzof the second main light emitting direction MED2-A on the XZ plane and the orthographic projection MED1xzof the first main light emitting direction MED1-A on the XZ plane, and there is an angle β4between the orthographic projection MED3xzof the third main light emitting direction MED3-A on the XZ plane and the orthographic projection MED1xzof the first main light emitting direction MED1-A on the XZ plane. In this embodiment, the orthographic projection MED2xzand the orthographic projection MED3xzof the second main light emitting direction MED2-A and the third main light emitting direction MED3-A on the XZ plane may be respectively located on the opposite sides of the orthographic projection MED1xzof the first main light emitting direction MED1-A on the XZ plane, and the angle β3and the angle β4may selectively be the same, but are not limited thereto.

Since the configuration relationship between the optical microstructure MS1-A, the optical microstructure MS2-A, and the optical microstructure MS3-A and the first light source121of this embodiment is similar, respectively, to the configuration relationship between the optical microstructure MS1, the optical microstructure MS2, and the optical microstructure MS3and the first light source121inFIG.1, detailed descriptions may be referred to in relevant paragraphs of the foregoing embodiments, and will not be described again here.

Based on the foregoing configuration, in the light source module10A of this embodiment, the first main light emitting direction MED1-A, the second main light emitting direction MED2-A, and the third main light emitting direction MED3-A are not parallel to each other in the dimension of the YZ plane, nor are they parallel to each other in the dimension of the XZ plane. Specifically, as shown in the schematic view ofFIG.5, the first main light emitting direction MED1-A emits in the forward direction, the second main light emitting direction MED2-A emits in the upper left direction, and the third main light emitting direction MED3-A emits in the lower right direction.

In particular, in this embodiment, the base angle α1″ of each optical microstructure MS1-A is the same, the base angle α2″ of each optical microstructure MS2-A is the same, and the base angle α3″ of each optical microstructure MS3-A is the same, but the disclosure is not limited thereto. In another embodiment, the angle of the base angle α1″ of each optical microstructure MS1-A may be varied gradually, the angle of the base angle α2″ of each optical microstructure MS2-A may be varied gradually, and the angle of the base angle α3″ of each optical microstructure MS3-A may be varied gradually. In this way, the brightness in each zone may also have slight changes in the dimension of the XZ plane. In yet another embodiment, for example, the light guide plate only has multiple optical microstructures MS1-A, and the multiple optical microstructures MS1-A may be divided into different microstructure groups, the angle of base angle α1″ of the optical microstructure MS1-A of each microstructure group is the same, but the angle of the base angle α1″ of the optical microstructure MS1-A of different microstructure groups is different. In this way, the brightness of the light emitting zone corresponding to each microstructure group may be different in the dimension of the XZ plane.

In this embodiment, when the user views the light guide plate100A at the left viewing angle inFIG.7Ain the dimension of the XZ plane, the brightness of the second zone Z2is higher than the light emitting brightness of each of the first zone Z1and the third zone Z3, and the light emitting brightness of the first zone Z1is higher than the light emitting brightness of the third zone Z3.

When the user views the light guide plate100A at the front viewing angle inFIG.7Bin the dimension of the XZ plane, the brightness of the first zone Z1is higher than the light emitting brightness of each of the second zone Z2and the third zone Z3, and the light emitting brightness of the second zone Z2is equivalent to the light emitting brightness of the third zone Z3.

When the user views the light guide plate100A at the right viewing angle inFIG.7Cin the dimension of the XZ plane, the brightness of the third zone Z3is be higher than the light emitting brightness of each of the second zone Z2and the first zone Z1, and the light emitting brightness of the first zone of Z1is higher than the light emitting brightness of the second zone Z2.

Since the brightness distribution change of the light guide plate100A of this embodiment when viewed at different viewing angles in the dimension of the YZ plane are similar to that of the light guide plate100inFIGS.4A to4C, detailed descriptions may be referred to in relevant paragraphs of the foregoing embodiments, and will not be described again here.

In this embodiment, when the user views the decorative pattern formed by the first zone Z1, the second zone Z2, and the third zone Z3at different viewing angles in the dimension of the YZ plane, the brightness distribution of the decorative patterns varies with the change of viewing angle, which in turn produces a dynamic effect with light and shadow changes. On the other hand, the light source module10A of this embodiment achieves the dynamic effect of light emitting distribution by arranging optical microstructures in different ways in different zones of the light guide plate100A, thus compared with the current method of increasing the number of light sources or selecting addressable light sources, the light source module10A also have lower production costs.

FIG.8is a schematic front view of a light source module according to a third embodiment of the disclosure.FIG.9Ais a schematic side view of the light source module ofFIG.8.FIG.9Bis a schematic cross-sectional view of the light source module ofFIG.8. Please refer toFIG.8,FIG.9A, andFIG.9B. The difference between a light source module10B of this embodiment and the light source module10ofFIG.1is that the number of light sources and the number of optical microstructures are different.

Specifically, in this embodiment, the light source module10B further includes a second light source122, a plurality of optical microstructures MS4, a plurality of optical microstructures MS5, and a plurality of optical microstructures MS6. The second light source122is disposed on one side of a second light incident surface100is2of a light guide plate100B. The second light incident surface100is2is connected to the bottom surface100bsand the first light incident surface100is1. The plurality of optical microstructures MS4(i.e. the third optical microstructures) are provided on the bottom surface100bsof the light guide plate100B and are located in the first zone Z1. The plurality of optical microstructures MS5(i.e. the fourth optical microstructures) are provided on the bottom surface100bsof the light guide plate100B and are located in the second zone Z2. The plurality of optical microstructures MS6are disposed on the bottom surface100bsof the light guide plate100B and located in the third zone Z3.

In this embodiment, the plurality of optical microstructures MS4located in the first zone Z1respectively has a light receiving surface rs4facing the second light source122. Each of the light receiving surfaces rs4has an edge e4connecting the bottom surface100bs.The plurality of optical microstructures MS5located in the second zone Z2respectively has a light receiving surface rs5. Each of the light receiving surfaces rs5has an edge e5connecting the bottom surface100bs.The plurality of optical microstructures MS6located in the third zone Z3respectively has a light receiving surface rs6. Each of the light receiving surfaces rs6has an edge e6connecting the bottom surface100bs.

It is particularly noted that a perpendicular bisector PB4of the edge e4passes through the second light source122(for example, an orthographic projection of the perpendicular bisector PB4on a virtual extended surface of the bottom surface100bspasses through an orthographic projection area of the second light source122on a virtual extended surface of the bottom surface100bs), but a perpendicular bisector PB5of the edge e5and a perpendicular bisector PB6of the edge e6do not pass through the second light source122. More specifically, in this embodiment, the perpendicular bisectors PB5of the plurality of optical microstructures MS5pass through the same side of the second light source122(for example, the left side of the second light source122inFIG.8, but not limited thereto), and the perpendicular bisectors PB6of the plurality of optical microstructures MS6pass through the same other side of the second light source122(for example, the right side of the second light source122inFIG.8, but not limited thereto).

For example, in this embodiment, the perpendicular bisector PB4of the edge e4of the light receiving surface rs4of each optical microstructure MS4passes through an emitting surface122esof the second light source122, for example, through a geometric center GC4of the emitting surface122es(i.e., the perpendicular bisectors of the edges e4of the light receiving surfaces rs4pass through a same side of the second light source122). In other words, the edges e4of the optical microstructures MS4are not necessarily parallel to each other. On the other hand, there is a virtual connection line between a geometric center GC5of the optical microstructure MS5(for example, the geometric center of the orthographic projection area of the optical microstructure MS5on the bottom surface100bs) and the geometric center GC4of the second light source122. The perpendicular bisector PB5of the edge e5of the light receiving surface rs5of each optical microstructure MS5deflects clockwise by an angle θ3relative to the virtual connection line, and the angle θ3deflected varies with the relative positions of the optical microstructure MS5and the second light source122. There is also a virtual connection line between a geometric center GC6of the optical microstructure MS6and the geometric center GC4of the second light source122. The perpendicular bisector PB6of the edge e6of the light receiving surface rs6of each optical microstructure MS6deflects counter-clockwise by an angle θ4relative to the virtual connection line, and the angle θ4deflected varies with the relative positions of the optical microstructure MS6and the second light source122. The clockwise deflection or counter-clockwise deflection mentioned here is, for example, the rotation of the optical microstructure along an axis (not shown) that passes through its geometric center and is parallel to the Z axis.

On the other hand, there is a base angle α4between the light receiving surface rs4of the optical microstructure MS4and the virtual extended surface of the bottom surface100bs.There is a base angle α5between the light receiving surface rs5of the optical microstructure MS5and the virtual extended surface of the bottom surface100bs.There is a base angle α6between the light receiving surface rs6of the optical microstructure MS6and the virtual extended surface of the bottom surface100bs.In this embodiment, the base angle α4of the optical microstructure MS4, the base angle α5of the optical microstructure MS5, and the base angle α6of the optical microstructure MS6are, for example, the same.

In this embodiment, the second light source122emits a fourth light L4, a fifth light L5, and a sixth light L6toward the optical microstructures MS4, the optical microstructures MS5, and the optical microstructures MS6respectively. The fourth light L4has a fourth main light emitting direction MED4after being reflected by the optical microstructures MS4. The fifth light L5has a fifth main light emitting direction MED5after being reflected by the optical microstructures MS5. The sixth light L6has a sixth main light emitting direction MED6after being reflected by the optical microstructures MS6.

It is particularly noted that the fourth main light emitting direction MED4of the fourth light L4reflected by the optical microstructure MS4, the fifth main light emitting direction MED5of the fifth light L5reflected by the optical microstructure MS5, and the sixth main light emitting direction MED6of the sixth light L6reflected by the optical microstructure MS6are different from each other.

Further, in this embodiment, the fourth main light emitting direction MED4may be parallel to the Z axis. That is, the first main light emitting direction MED1is perpendicular to the light emitting surface100esof the light guide plate100(i.e., the XY plane). However, neither the fifth main light emitting direction MED5nor the sixth main light emitting direction MED6is parallel to the Z axis. More specifically, an orthographic projection MED5xzof the fifth main light emitting direction MED5on the XZ plane has an axial component in the opposite direction to the X axis, and an orthographic projection MED6xzof the sixth main light emitting direction MED6on the XZ plane has an axial component in the same direction as the X axis.

From another point of view, there is an angle5between the orthographic projection MED5xzof the fifth main light emitting direction MED5on the XZ plane and an orthographic projection MED4xzof the fourth main light emitting direction MED4on the XZ plane, and there is an angle β6between the orthographic projection MED6xzof the sixth main light emitting direction MED6on the XZ plane and the orthographic projection MED4xzof the fourth main light emitting direction MED4on the XZ plane. In this embodiment, the orthographic projection MED5xzand the orthographic projection MED6xzof the fifth main light emitting direction MED5and the sixth main light emitting direction MED6on the XZ plane may be respectively located on opposite sides of the orthographic projection MED4xzof the fourth main light emitting direction MED4on the XZ plane, and the angle β5and the angle β6may selectively be the same, but are not limited thereto.

In particular, since the base angle α4of the optical microstructure MS4, the base angle α5of the optical microstructure MS5and the base angle α6of the optical microstructure MS6of this embodiment are all the same, the fourth main light emitting direction MED4, the fifth main light emitting direction MED5, and the sixth main light emitting direction MED6are all parallel to the second light incident surface100is2or the XZ plane of the light guide plate100B. That is, an orthographic projection MED4yz,an orthographic projection MED5yz,and an orthographic projection MED6yzof the fourth main light emitting direction MED4, the fifth main light emitting direction MED5, and the sixth main light emitting direction MED6respectively on the YZ plane do not have axial components that are in the same direction as or in the opposite direction to the Y axis.

That is, in this embodiment, the fourth main light emitting direction MED4, the fifth main light emitting direction MED5, and the sixth main light emitting direction MED6are not parallel to each other in the dimension of the XZ plane (as shown inFIG.9A), but are parallel to each other in the dimension of the YZ plane (as shown inFIG.9B).

Since the configuration relationship between the optical microstructure MS1, the optical microstructure MS2and the optical microstructure MS3and the first light source121of this embodiment is similar, respectively, to the configuration relationship of the optical microstructure MS1, the optical microstructure MS2, and the optical microstructure MS3and the first light source121inFIG.1, detailed descriptions may be referred to in relevant paragraphs of the foregoing embodiments, and will not be described again here.

In particular, the light source module10A inFIGS.5toFIG.6Bachieves the dynamic effect of its light emitting distribution in the dimension of the XZ plane by using different base angles of the optical microstructures (as shown inFIGS.7A to7C). However, in this embodiment, the light source module10B achieves the dynamic effect of its light emitting distribution in the dimension of the XZ plane by adding a second set of light sources and optical microstructures.

FIG.10is a schematic front view of a light source module according to a fourth embodiment of the disclosure. Please refer toFIG.10. The difference between a light source module10C of this embodiment and the light source module10ofFIG.1is that the number of light sources are different. For example, in this embodiment, the light source module10C further includes an auxiliary light source123and an auxiliary light source125, which are disposed on one side of the first light incident surface100is1of the light guide plate100and respectively located on opposite sides of the first light source121. The auxiliary light source125, the first light source121, and the auxiliary light source123are arranged in sequence along the Y direction, for example (the Y direction is, for example, parallel to the first light incident surface100is1and parallel to the light emitting surface100es). The distance between the center of the emitting surface of the auxiliary light source123and the center of the emitting surface121esof the first light source121is, for example, within the range of two to ten times the width of the emitting surface121esof the first light source121in the Y direction. The distance between the center of the emitting surface of the other auxiliary light source125and the center of the emitting surface121esof the first light source121is, for example, within the range of two to ten times the width of the emitting surface121esof the first light source121in the Y direction.

It is particularly noted that the auxiliary light source123, the auxiliary light source125, and the first light source121respectively have different light emitting brightness. For example, in this embodiment, the light emitting brightness of the auxiliary light source123may be smaller than the light emitting brightness of the first light source121and larger than the light emitting brightness of the auxiliary light source125, but is not limited thereto. Accordingly, the dynamic effect with light and shadow changes between different zones on the light guide plate100can be further improved. Preferably, the percentage value of the respective light emitting brightness of the auxiliary light source123and the auxiliary light source125to the light emitting brightness of the first light source121may be less than 60%.

However, the disclosure is not limited thereto. The light color of at least one of the auxiliary light source123and the auxiliary light source125may also be different from the light color of the first light source121. Accordingly, the dynamic effect with the colors of different zones on the light guide plate100changing with the viewing angle can also be increased. Similarly, in the light source module10B ofFIG.8, the light colors of the first light source121and the second light source122may also be selectively different to further increase the dynamic effect with the colors of different zones on the light guide plate100B changing with the viewing angle.

FIG.11is a schematic front view of a light source module according to the fifth embodiment of the disclosure. Please refer toFIG.11. The difference between a light source module10D of this embodiment and the light source module10C ofFIG.10is that the driving circuits for the first light source121and the auxiliary light source are different. Specifically, in this embodiment, the first light source121, an auxiliary light source123a,and an auxiliary light source125aare connected in parallel, the first light source121, the auxiliary light source123a,and the auxiliary light source125aare respectively connected in series with a first resistor R1, a second resistor R2, and a third resistor R3, and the resistance values of these resistors are different from each other.

By connecting multiple resistors with different resistance values in series with light sources, the flexibility of selecting the first light source121, the auxiliary light source123a,and the auxiliary light source125acan be increased. For example, multiple light-emitting elements with the same maximum light emitting brightness may be used, and then the light emitting brightness of each of these light-emitting elements may be controlled by connecting resistors with different resistance values in series. Accordingly, the dynamic effect with light and shadow changes between different zones on the light guide plate100can be further improved.

FIG.12is a schematic front view of a light source module according to a sixth embodiment of the disclosure. Please refer toFIG.12. The difference between a light source module10E of this embodiment and the light source module10C ofFIG.10is that the configuration of the light guide plate is different. For example, in this embodiment, a first light incident surface100is1-A of a light guide plate100E of the light source module10E has a first sub-surface100is1a,a second sub-surface100is1b,and a third sub-surface100is1c.The first light source121is disposed corresponding to the first sub-surface100is1a.An auxiliary light source123bis disposed corresponding to the second sub-surface100is1b.An auxiliary light source125bis disposed corresponding to the third sub-surface100is1c.

There is a first spacing S1between the first light source121and the first sub-surface100is1aalong the direction X, there is a second spacing S2between the auxiliary light source123band the second sub-surface100is1balong the direction X, and there is a third spacing S3between the auxiliary light source125band the third sub-surface100is1calong the direction X. It is particularly noted that in this embodiment, the second spacing S2is larger than the first spacing S1and smaller than the third spacing S3. That is, the first spacing S1, the second spacing S2, and the third spacing S3are different from each other. For example, the second spacing S2is two times to four times the first spacing S1, and the third spacing S3is three times to six times the first spacing S1.

Since the optical coupling efficiency between the light source and the light guide plate decreases as the distance between the light source and the light guide plate increases, the brightness of the light emitted by the auxiliary light source123band coupled to the light guide plate100E is smaller than the brightness of the light emitted by the first light source121and coupled to the light guide plate100E, but is larger than the brightness of the light emitted by the auxiliary light source125band coupled to the light guide plate100E. Accordingly, the dynamic effect with light and shadow changes between different zones on the light guide plate100E can be further improved.

To sum up, in the light source module according to an embodiment of the disclosure, on the bottom surface of the light guide plate, a plurality of first optical microstructures are provided in the first zone, and a plurality of second optical microstructures are provided in the second zone. The perpendicular bisector of the first edge of the first light receiving surface of the first optical microstructure passes through the first light source, but the perpendicular bisector of the second edge of the second light receiving surface of the second optical microstructure does not pass through the first light source. Through such a configuration, the main light emitting direction of the light emitted by the first light source after being reflected by the first optical microstructure is different from the main light emitting direction of the light emitted by the first light source after being reflected by the second optical microstructure. Thus, the relationship between the light emitting brightness of the first zone and the second zone may vary with different viewing angles, thereby showing a dynamic effect of changing light emitting distribution.