TW201732188A - Direct type illumination device and display device - Google Patents

Abstract

A direct type illumination device includes a light emitting diode (LED) unit, a lens, and a photoluminescence layer. The lens is disposed corresponding to the LED unit, and the photoluminescence layer is disposed between the lens and the LED unit. The lens is a lens with a concave center. Two cambered surfaces are located on two opposite sides of a lens center of the lens in a horizontal direction. Each cambered surface has a peak value point. A cambered surface peak width between the two peak value points of the two cambered surfaces is larger than or equal to one eighth of a width of the lens in the horizontal direction. The required illumination distribution of the direct type illumination device may be obtained by the specification of the lens, and the illumination performance of the direct type illumination device may be improved accordingly.

Description

Direct type light emitting device and display

The present invention relates to a direct type illuminating device and a display, and more particularly to a direct type illuminating device having a centrally concave lens and a display.

Light-emitting diodes have been widely used in traffic signs, decorative lighting, and light sources of various electronic products because of their low power consumption, long component life, low driving voltage, and fast response speed. Backlight modules made with light-emitting diodes are now also found in many flat-panel display products.

Since the backlight source required in a general flat panel display is mostly a white light source, the white light emitting diode still has problems such as poor color purity, complicated structure, and high production cost, and therefore needs to be generated by using a blue light emitting diode. The way in which the blue light excites the photoluminescent material produces white light. However, since the intensity distribution of the excitation light generated by the photoluminescent material varies with the material properties of the photoluminescent material, if the intensity distribution of the excitation light corresponding to each of the light-emitting diodes is not adjusted by other means, When a plurality of light-emitting diodes are combined with a photoluminescent material to form a direct-type backlight module, problems such as a total light-emitting luminance distribution and/or a degree of color conversion unevenness, such as a yellow spot phenomenon, are apt to occur.

One of the main objects of the present invention is to provide a direct-lit light-emitting device and a display, which are provided with a central concave lens by using a corresponding light-emitting diode unit and a photoluminescent layer, and limiting the peak width between the curved surface of the lens and the lens width. The proportional relationship is adopted to adjust the luminous intensity distribution of the direct-lit light-emitting device to meet the required requirements, thereby improving the overall luminous effect of the direct-lit light-emitting device.

In order to achieve the above object, a preferred embodiment of the present invention provides a direct type light emitting device. The direct type light emitting device includes a light emitting diode unit, a lens, and a photoluminescent layer. The lens is disposed corresponding to the light emitting diode unit, and the photoluminescent layer is disposed between the lens and the light emitting diode unit. The lens is a central concave lens and has a lens center. In a horizontal direction, the opposite sides of the lens center respectively have a curved surface, each curved surface has a peak point, and a curved surface width between the two peak points of the two curved surfaces . The surface peak width is greater than or equal to one-eighth of the lens width of the lens in the horizontal direction.

In order to achieve the above object, a preferred embodiment of the present invention provides a display. The display includes a direct type light emitting device and a display panel. The direct type light emitting device includes a light emitting diode unit, a lens, and a photoluminescent layer. The lens is disposed corresponding to the light emitting diode unit, and the photoluminescent layer is disposed between the lens and the light emitting diode unit. The lens is a central concave lens and has a lens center. In a horizontal direction, the opposite sides of the lens center respectively have a curved surface, each curved surface has a peak point, and a curved surface width between the two peak points of the two curved surfaces . The surface peak width is greater than or equal to one-eighth of the lens width of the lens in the horizontal direction. The display panel is disposed on the direct type light emitting device, and the direct type light emitting device includes a backlight module.

The present invention will be further understood by those of ordinary skill in the art to which the present invention pertains. .

Please refer to Figures 1 to 3. 1 is a cross-sectional view of a display according to a first embodiment of the present invention, FIG. 2 is a cross-sectional view of the direct-lit light-emitting device of the present embodiment, and FIG. 3 is a schematic view showing the light-emitting device of the present embodiment. Schematic diagram of the intensity distribution. As shown in FIGS. 1 and 2, the present embodiment provides a display 300 including a direct type light emitting device 101 and a display panel 90. In the display 300, the direct-lit light-emitting device 101 can be a backlight module for providing a light source of the display panel 90 to achieve a display effect, but the invention is not limited thereto. In other embodiments of the invention, the direct-lit light-emitting device 101 can also be used as, for example, illumination or other suitable use as desired. In this embodiment, the display panel 90 may include a liquid crystal display panel, an electro-wetting display panel, or other suitable non-self-luminous display panel, but is not limited thereto. In addition, the display 300 may further include other optical films 70 and/or diffusion sheets 60. The optical film 70 and the diffusion sheet 60 are disposed between the direct-type light-emitting device 101 and the display panel 90 for further adjustment into the display panel 90. The light condition.

In the present embodiment, the direct type light emitting device 101 may include a light emitting diode unit 20, a photoluminescent layer 30, and a lens 40. The lens 40 is disposed corresponding to the light emitting diode unit 20, and the photoluminescent layer 30 is disposed between the lens 40 and the light emitting diode unit 20. In this embodiment, the light emitting diode unit 20, the photoluminescent layer 30, and the lens 40 may be disposed on the substrate 10, and the substrate 10 may also be provided with a reflective layer 11 for reflecting light to the light exiting direction. In addition, in the drawings attached to the present invention, only one set of the light emitting diode unit 20, the photoluminescent layer 30 and the lens 40 are illustrated for convenience of explanation, and the luminous intensity distribution diagram of each direct type light emitting device is shown. It also represents only a set of luminous intensity distributions produced by the combination of the light-emitting diode unit 20, the photoluminescent layer 30 and the lens 40. However, the direct-type light-emitting device of the present invention does not have a set of the light-emitting diode unit 20, the photo-luminescence layer 30 and the lens 40, and is visually designed to include a complex array of light-emitting diode units 20 and photoluminescence. Layer 30 and lens 40. In the present embodiment, the lens 40 is a centrally concave lens, and the centrally concave lens may be a reflective lens. The lens 40 is, for example, a circular lens. When the cross-sectional view is closed, the lens center 40C of the lens 40 has a curved surface 40S on opposite sides of the horizontal direction D1, and each curved surface 40S has a peak point 40P, which is opposite to the two curved surfaces 40S. There is a curved peak width W1 between the two peak points 40P; in other words, from the lens center 40C to the peripheral side, the lens 40 has a curved surface 40S having two opposite peak points 40P in the direction in which any lens diameter W2 extends, relative to the two peaks The distance between the points 40P is the curved surface peak diameter W1. In addition, the lens center 40C preferably corresponds to the light emitting diode unit 20, and the curved surface 40S is a side of the lens 40 away from the light emitting diode unit 20, and a side of the lens 40 adjacent to the light emitting diode unit 20 may be a flat surface. The curved surface peak width (or diameter) W1 is greater than one-eighth of the lens width (or diameter) W2 of the lens 40 in the horizontal direction D1 for enabling the luminous intensity distribution of the direct-lit light-emitting device 101 to meet the required requirements. For example, the photoluminescent layer 30 of the embodiment may be a quantum dot photoluminescent layer, the LED unit 20 may be a blue light emitting diode unit, and the blue light emitted by the LED unit 20 may be excited. The photoluminescent layer 30 generates white light excitation light, but the invention is not limited thereto. Other types of photoluminescent layer 30 or/and LED unit 20 may also be used in other embodiments of the invention to achieve the desired light extraction effect. However, in the above-mentioned quantum dot photoluminescence layer combined with the blue light emitting diode unit to generate white light excitation light, if the color conversion at different positions is uneven due to the distribution of the viewing angle of the light, the yellow spot phenomenon is likely to occur. To illuminate and display effects. Therefore, in order to solve the above-mentioned macular phenomenon, there must be special requirements for the distribution of the luminous intensity of the direct-lit light-emitting device 101. For example, the angle corresponding to the peak point of the luminous intensity distribution must be greater than 60 degrees, and the central intensity and peak intensity of the luminous intensity distribution. The ratio needs to be less than 30%, and the ratio of the luminous intensity to the peak intensity between 20 and 40 degrees is less than 50%. As shown in FIG. 3, in the setting of the lens 40 of the present embodiment, the peak point of the luminous intensity distribution corresponds to an angle greater than 60 degrees (about 63 to 64 degrees), and the central intensity and peak intensity of the luminous intensity distribution. The ratio is less than 30% (the ratio of intensity to peak intensity at 0 degrees is about 21% to 23%), and the ratio of the intensity of the light to the peak intensity between 20 and 40 degrees is less than 50% (about 17%~25%), so it can meet the above luminous intensity distribution requirements.

Please refer to Figure 2, Figure 4, Figure 5, Figure 6, and Table 1 below. 4 is a schematic diagram showing a luminous intensity distribution of a direct type light-emitting device according to a first comparative example of the present invention, and FIG. 5 is a schematic diagram showing a luminous intensity distribution of a direct-type light-emitting device according to a second comparative example of the present invention, and FIG. 6 is a view A schematic diagram of the luminous intensity distribution of the direct type light-emitting device of the third comparative example is shown, and Table 1 lists the ratio of the peak width of the curved surface to the lens width of the first comparative example to the third comparative example. That is, the first comparative example to the third comparative example can be regarded as a result of changing the ratio of the curved surface peak width W1 to the lens width W2 based on the structure of the first embodiment. As shown in FIG. 2, FIG. 4, FIG. 5, FIG. 6, and the following Table 1, when the ratio of the curved surface peak width W1 to the lens width W2 is less than 1/8, the condition of the first comparative example of FIG. 4 is as shown in FIG. The luminous intensity distribution condition cannot meet the above requirements in order to solve the macular phenomenon, and relatively speaking, when the ratio of the curved surface peak width W1 to the lens width W2 is greater than or equal to 1/8 (as shown in FIG. 5, the second comparative example) In the case of the third comparative example of Fig. 6, in the case of the luminous intensity distribution, the peak corresponding to the luminous intensity distribution has an angle greater than 60 degrees (about 64 to 65 degrees), and the central intensity and peak intensity of the luminous intensity distribution. The ratio is less than 30% (the ratio of the intensity to the peak intensity at 0 degrees is about 28%, 18%), and the ratio of the illuminance to the peak intensity between 20 and 40 degrees is less than 50%. It is 21%~31%, 13%~21%), so it can meet the above requirements in order to solve the macular phenomenon. It can be seen that the curved surface peak width W1 is greater than or equal to one-eighth of the lens width W2 of the lens 40 in the horizontal direction D1, which is a necessary condition for solving the yellow spot phenomenon. Table 1

In addition, as shown in FIGS. 1 and 2, the direct-lit light-emitting device 101 may further include a light control film 50 having a perforation and reflection function disposed above the lens 40, and the photoluminescent layer 30 and the light-emitting layer The diode units 20 are separated by an air layer G to have a gap, and are mixed by the light mixing space SP between the reflective layer 11 and the diffusion sheet 60 to form a direct-lit light-emitting effect, but This is limited to this. The light-regulating film 50 is disposed such that the height of the lens that can be placed is close to the requirement of the flat lens 40 of the embodiment, and the light-emitting layer 30 and the light-emitting diode unit 20 are separated by the air layer G to reduce the thermal effect and stabilize the color. The effect of the property, and the combination of the photoluminescent layer 30 and the lens 40 can maintain a wide intensity viewing angle distribution effect and can be used to solve the yellow spot problem caused by uneven color conversion at different positions. However, since the illuminating field type of the illuminating diode unit 20 is a Lambertian type, the optical effect (low center intensity and bimodal distribution) caused by the lens 40 when the illuminating diode unit 20 is away from the lens 40 It will fall accordingly, so the distance between the photoluminescent layer 30 and the gap between the light-emitting diode units 20 should not be too large. For example, the distance H3 between the photoluminescent layer 30 and the light emitting diode unit 20 of the present embodiment is preferably smaller than the light emitting surface width W3 of the light emitting diode unit 20 in the horizontal direction D1, and the light is The distance H3 between the light-emitting layer 30 and the light-emitting diode unit 20 is preferably less than 0.5 mm, but is not limited thereto. In addition, when the light emitting surface of the light emitting diode unit 20 is too close to the lens 40 and the photoluminescent layer 30, since the photoluminescent layer 30 is susceptible to thermal effects, the glass can be packaged, and the lens 40 can also be made of glass. Made to avoid thermal deformation, but not limited to this.

Further, the requirements of the specifications of the lens 40, the photoluminescent layer 30, and the light-emitting diode unit 20 and the relative relationship between each other in the direct-type light-emitting device 101 of the present embodiment will be further described, wherein the peak of the curved surface 40S of the lens 40 is further described. The height H1 of the point 40P is preferably less than one eighth of the lens width W2, thereby forming a flat lens 40. Further, the thickness of the edge of the lens 40 is preferably smaller than the distance between the peak point 40P of the curved surface 40S and the upper surface 30T of the photoluminescent layer 30 (it can also be regarded as the height H1 of the peak point 40P as shown in FIG. 2). That is, the peak point 40P of the lens 40 is the thickest position of the lens 40, and the thickness from the peak point 40P to the periphery is gradually smaller. In this case, the height of the side of the lens 40 is low, whereby the intensity of the center of illumination can be lowered, so that the required number of the light-emitting diode units 20 in the direct-lit type light-emitting device can be reduced or the size of the lens 40 can be reduced. Need width. However, in order to ensure the optical effect of the lens 40, the height H1 of the peak point 40P is not too small. In the present embodiment, the height H1 of the peak point 40P of the curved surface 40S is preferably greater than that of the LED unit 20 in the horizontal direction D1. The light emitting surface has a width W3. For example, please refer to Figure 2, Figure 7 to Figure 10, and Table 2 below. 7 is a schematic view showing a direct type light-emitting device 201 according to a fourth comparative example of the present invention, and FIG. 8 is a schematic view showing a light-emission intensity distribution of the direct-type light-emitting device 201 of the fourth comparative example of the present invention, and FIG. 9 is a view showing the present invention. FIG. 10 is a schematic diagram showing a luminous intensity distribution of a direct type light-emitting device according to a sixth comparative example of the present invention, and FIG. 2 is a fourth comparative example to a sixth The ratio of the height of the peak point of the curved surface of the comparative example to the width of the light-emitting surface of the light-emitting diode unit. That is, the fourth comparative example to the sixth comparative example can be regarded as a result of changing the ratio of the height H1 of the peak point 40P of the curved surface 40S to the light-emitting surface width W3 of the light-emitting diode unit 20 based on the structure of the first embodiment. . Here, as shown in FIG. 7, the height H1 of the peak point 40P of the fourth comparative example is smaller than the height H1 of the peak point 40P of the first embodiment (as shown in FIG. 2), so that the peak of the fourth comparative example is made. The ratio of the height H1 of the point 40P to the light-emitting surface width W3 of the light-emitting diode unit 20 becomes small, which is about 1.1. As shown in Fig. 2, Fig. 7, Fig. 8, Fig. 9, Fig. 10, and Table 2 below, when the ratio of the height H1 of the peak point 40P to the width W3 of the light emitting surface is less than 1.2 (Fig. 8) In the case of the four comparative examples, the ratio of the center intensity of the luminous intensity distribution to the peak intensity is about 44%, which is greater than 30%. Therefore, the distribution of the luminous intensity cannot meet the above requirements in order to solve the macular phenomenon, but relatively speaking. When the ratio of the height H1 of the peak point 40P to the width W3 of the light-emitting surface is greater than or equal to 1.2 (as in the fifth comparative example of FIG. 9 and the sixth comparative example of FIG. 10), the luminous intensity distribution can be consistent with the above. In order to solve the requirement of the macula phenomenon, it can be seen that the larger the ratio, the more the luminous intensity distribution is in line with the demand. It can be seen that the height H1 of the peak point 40P of the curved surface 40S needs to be at least equal to or greater than 1.2 times the width W3 of the light-emitting surface of the light-emitting diode unit 20 in the horizontal direction D1, and the height H1 of the peak point 40P is preferably greater than or It is equal to 1.5 times the width W3 of the light-emitting surface of the light-emitting diode unit 20. The height H1 of the peak point 40P of the lens 40 is increased to lower the luminous intensity of the center 40C or the size of the lens 40 can be further reduced. Table 2

As shown in FIG. 2, each curved surface 40S of the lens 40 has a first segment R1 and a second segment R2 respectively located on both sides of the peak point 40P in the horizontal direction D1, and the first segment R1 is located at the center 40C of the lens 40 and the first portion Two segments between R2. The maximum value of the absolute value of the slope of the first segment R1 of the curved surface 40S is greater than the maximum value of the absolute value of the slope of the second segment R2, and the projection of the first segment R1 in the vertical direction D2 falls within the range of the photoluminescent layer 30. The projection portion of the second segment R2 in the vertical direction D2 falls within the range of the photoluminescent layer 30.

Please refer to Figure 2, Figure 3, Figure 11, and Figure 12. 11 is a schematic view showing a direct type light-emitting device 202 of a seventh comparative example of the present invention, and FIG. 12 is a schematic view showing a light-emission intensity distribution of the direct-type light-emitting device 202 of the seventh comparative example. As shown in FIG. 2, FIG. 3, FIG. 11 and FIG. 12, the direct type light-emitting device 202 of the seventh comparative example is different from the direct-type light-emitting device 101 of the first embodiment in the seventh comparative example. The direct-lit illuminating device 202 has a relatively large illuminating diode unit 20, however, the illuminating intensity distribution of the seventh comparative example does not meet the above requirements in order to solve the macular phenomenon, and the peak point of the illuminating intensity distribution corresponds to an angle of about It is 4 degrees and not more than 60 degrees, as shown in Figure 12. Therefore, it is understood that the light-emitting surface width W3 of the light-emitting diode unit 20 in the horizontal direction D1 is preferably smaller than the curved surface peak width W1, so that the lens 40 can match the light generated by the light-emitting diode unit 20 to obtain the desired light. Luminous intensity distribution. In addition, please refer to Figure 2, Figure 13 to Figure 18, and Table 3 below. 13 is a schematic diagram showing a luminous intensity distribution of a direct type light-emitting device according to an eighth comparative example of the present invention, and FIG. 14 is a schematic diagram showing a luminous intensity distribution of a direct-type light-emitting device according to a ninth comparative example of the present invention, and FIG. 15 is a view FIG. 16 is a schematic diagram showing a luminous intensity distribution of a direct type light-emitting device according to an eleventh comparative example of the present invention, and FIG. 17 is a twelfth comparison of the present invention. FIG. 18 is a schematic diagram showing a luminous intensity distribution of a direct type light-emitting device according to a thirteenth comparative example of the present invention, and Table 3 lists an eighth comparative example to a thirteenth comparison. The ratio of the width of the photoluminescent layer to the width of the light emitting surface of the light emitting diode unit. That is, the eighth comparative example to the thirteenth comparative example can be regarded as a result of changing the ratio of the width W4 of the photoluminescent layer 30 to the light emitting surface width W3 of the light emitting diode unit 20 based on the structure of the first embodiment. . As shown in FIG. 2, FIG. 13 to FIG. 18, and the following Table 3, the ninth comparative example to the twelfth comparative example can all meet the above-described luminous intensity distribution requirement for solving the macular phenomenon, and the eighth comparative example (eg, Figure 13) does not meet this requirement, the peak point of the luminous intensity distribution corresponds to an angle less than 60 degrees, and the thirteenth comparative example (as shown in Figure 18) does not meet this requirement, and its luminous intensity The ratio of the center intensity to the peak intensity of the distribution is about 38% to 43% greater than 30%. Therefore, in order to obtain a desired distribution of luminous intensity, the width W4 of the photoluminescent layer 30 in the horizontal direction D1 needs to be greater than or equal to 1.2 times and less than the width W3 of the luminous surface of the luminous diode unit 20 in the horizontal direction D1. Or equal to 5.2 times the width W3 of the light emitting surface of the light emitting diode unit 20 in the horizontal direction D1, and preferably, the width W4 of the photoluminescent layer 30 may be greater than or equal to 1.4 times and less than or equal to the width W3 of the light emitting surface. The luminous surface width is 1.6 times the width W3. table 3

Please refer to Figure 2, Figure 19 and Figure 20. 19 is a schematic view showing a direct-type light-emitting device 203 of a fourteenth comparative example of the present invention, and FIG. 20 is a schematic view showing a light-emission intensity distribution of the direct-type light-emitting device 203 of the fourteenth comparative example. As shown in FIG. 2, FIG. 19, and FIG. 20, the distance between the peak point 40P of the curved surface 40S of the lens 40 and the upper surface 30T of the photoluminescent layer 30 can also be regarded as shown in FIG. The height H1) of the peak point 40P is preferably larger than the thickness H2 of the photoluminescent layer 30, because in the case of the thicker photoluminescent layer 30 (as in the case of Fig. 19), the light emitting diode unit 20 is caused. The light emitting surface 20T is away from the lens 40, thereby causing the optical effect (low center intensity and bimodal distribution) required by the lens 40 to be lowered (as effected in Fig. 20).

Therefore, there must be a special requirement for the luminous intensity distribution state of the direct type light-emitting device 101 in order to solve the yellow spot phenomenon, and the specifications of the lens 40, the photoluminescence layer 30, and the light-emitting diode unit 20 in this embodiment and The requirement of the relative relationship between each other, for example, the ratio of the curved surface peak width W1 to the lens width W2 needs to be greater than or equal to 1/8, and the height H1 of the peak point 40P of the curved surface 40S is preferably less than one eighth of the lens width W2, and the curved surface 40S The height H1 of the peak point 40P is preferably larger than the light-emitting surface width W3 of the light-emitting diode unit 20, and the light-emitting surface width W3 of the light-emitting diode unit 20 is preferably larger than that of the photoluminescent layer 30 and the light-emitting diode unit 20. The distance H3 or the like between the direct light-emitting devices 101 can be made to satisfy the required requirements, and the yellow light phenomenon can be solved to improve the overall light-emitting effect of the direct-type light-emitting device 101.

Please refer to Figure 2 and Figure 21. 21 is a schematic view showing a direct type light-emitting device 102 according to a second embodiment of the present invention. As shown in FIGS. 21 and 2, the direct type light-emitting device 102 of the present embodiment is different from the direct-type light-emitting device 101 of the first embodiment in that the curved surface peak of the lens 40 is in the direct-type light-emitting device 102. The width W1 is greater than the width W4 of the photoluminescent layer 30 in the horizontal direction D1, that is, the photoluminescent layer 30 of the present embodiment is relatively small, thereby not affecting the required distribution of luminous intensity. The amount of the photoluminescent layer 30 is reduced, and the effect of reducing the manufacturing cost can be achieved. On the other hand, as shown in FIG. 2, the curved surface peak width W1 may be smaller than the width W4 of the photoluminescent layer 30 in the horizontal direction D1, whereby the relatively large photoluminescent layer 30 can be used to enhance the color. Conversion effect. In other words, the relative relationship between the above-described curved surface peak width W1 and the width W4 of the photoluminescent layer 30 can be adjusted according to different purposes (manufacturing cost or color conversion effect).

In summary, in the direct-type light-emitting device and the display of the present invention, the central concave lens is disposed corresponding to the light-emitting diode unit and the photoluminescent layer, and by limiting the curved peak width and the lens width of the lens The proportional relationship between the two, and the requirements for the relative specifications of the lens, the photoluminescent layer and the light-emitting diode unit, and the relative relationship between the two, can make the luminous intensity distribution of the direct-lit light-emitting device meet the required requirements, thereby improving the direct The overall luminous effect of the illuminating device. The above are only the preferred embodiments of the present invention, and all changes and modifications made to the scope of the present invention should be within the scope of the present invention.

10‧‧‧Substrate
11‧‧‧reflective layer
20‧‧‧Lighting diode unit
20T‧‧‧Lighting surface
30‧‧‧Photoluminescent layer
30T‧‧‧ upper surface
40‧‧‧ lens
40C‧‧ Center
40P‧‧‧ peak point
40S‧‧‧ surface
50‧‧‧Light control diaphragm
70‧‧‧Optical film
60‧‧‧Diffuser
90‧‧‧ display panel
101-102, 201-203‧‧‧ Direct type illuminating device
300‧‧‧ display
D1‧‧‧ horizontal direction
D2‧‧‧Vertical direction
G‧‧‧ air layer
H1‧‧‧ Height
H2‧‧‧ thickness
H3‧‧‧ distance
First paragraph of R1‧‧
Second paragraph of R2‧‧
SP‧‧‧Hybrid space
W1‧‧‧ peak width
W2‧‧‧ lens width
W3‧‧‧Lighting surface width
W4‧‧‧Width

1 is a cross-sectional view showing a display of a first embodiment of the present invention. 2 is a cross-sectional view showing a direct type light-emitting device according to a first embodiment of the present invention. FIG. 3 is a schematic view showing the distribution of luminous intensity of the direct type light-emitting device according to the first embodiment of the present invention. Fig. 4 is a schematic view showing the distribution of luminous intensity of the direct type light-emitting device of the first comparative example of the present invention. Fig. 5 is a schematic view showing the distribution of luminous intensity of the direct type light-emitting device of the second comparative example of the present invention. FIG. 6 is a schematic view showing the distribution of luminous intensity of the direct type light-emitting device of the third comparative example of the present invention. Fig. 7 is a schematic view showing a direct type light-emitting device of a fourth comparative example of the present invention. FIG. 8 is a schematic view showing the distribution of luminous intensity of the direct type light-emitting device of the fourth comparative example of the present invention. FIG. 9 is a schematic view showing the distribution of luminous intensity of the direct type light-emitting device of the fifth comparative example of the present invention. FIG. 10 is a schematic view showing the distribution of luminous intensity of the direct type light-emitting device of the sixth comparative example of the present invention. 11 is a schematic view showing a direct type light-emitting device of a seventh comparative example of the present invention. Fig. 12 is a view showing the distribution of luminous intensity of the direct type light-emitting device of the seventh comparative example of the present invention. Fig. 13 is a view showing the distribution of luminous intensity of the direct type light-emitting device of the eighth comparative example of the present invention. Fig. 14 is a view showing the distribution of luminous intensity of the direct type light-emitting device of the ninth comparative example of the present invention. Fig. 15 is a view showing the distribution of luminous intensity of the direct type light-emitting device of the tenth comparative example of the present invention. Fig. 16 is a view showing the distribution of luminous intensity of the direct type light-emitting device of the eleventh comparative example of the present invention. Fig. 17 is a view showing the distribution of luminous intensity of the direct type light-emitting device of the twelfth comparative example of the present invention. Fig. 18 is a view showing the distribution of luminous intensity of the direct type light-emitting device of the thirteenth comparative example of the present invention. Figure 19 is a schematic view showing a direct type light-emitting device of a fourteenth comparative example of the present invention. Fig. 20 is a view showing the distribution of luminous intensity of the direct type light-emitting device of the fourteenth comparative example of the present invention. Figure 21 is a schematic view showing a direct type light-emitting device according to a second embodiment of the present invention.

10‧‧‧Substrate

11‧‧‧reflective layer

20‧‧‧Lighting diode unit

20T‧‧‧Lighting surface

30‧‧‧Photoluminescent layer

30T‧‧‧ upper surface

40‧‧‧ lens

40C‧‧ Center

40P‧‧‧ peak point

40S‧‧‧ surface

101‧‧‧Direct type illuminating device

D1‧‧‧ horizontal direction

D2‧‧‧Vertical direction

G‧‧‧ air layer

H1‧‧‧ Height

H2‧‧‧ thickness

H3‧‧‧ distance

First paragraph of R1‧‧

Second paragraph of R2‧‧

W1‧‧‧ peak width

W2‧‧‧ lens width

W3‧‧‧Lighting surface width

W4‧‧‧Width

Claims (19)

A direct type light emitting device comprising: a light emitting diode unit; a lens disposed corresponding to the light emitting diode unit, wherein the lens is a central concave lens and has a lens center, the lens is in a horizontal direction The opposite sides of the center respectively have a curved surface, each of the curved surfaces has a peak point, and the two peak points of the two curved surfaces have a curved peak width, wherein the curved surface peak width is greater than or equal to the lens in the horizontal direction. One eighth of the width of the lens; and a photoluminescent layer disposed between the lens and the light emitting diode unit. The direct type illuminating device of claim 1, wherein a height of the peak point of the curved surface is less than one eighth of a width of the lens. The direct type light-emitting device of claim 1, wherein the height of the peak point of the curved surface is greater than or equal to 1.2 times the width of the light-emitting surface of the light-emitting diode unit in the horizontal direction. The direct-type light-emitting device of claim 1, wherein the photoluminescent layer and the light-emitting diode have a gap, and the light-emitting diode unit has a light-emitting surface width greater than the light in the horizontal direction. The distance between the light-emitting layer and the light-emitting diode unit. The direct type illuminating device of claim 1, wherein the curved surface has a first segment and a second segment respectively located on opposite sides of the peak point in the horizontal direction, and the absolute value of the absolute value of the first segment is The greater than the maximum value of the absolute value of the slope of the second segment, and the first segment is between the center of the lens and the second segment. The direct-lit light-emitting device of claim 5, wherein the projection of the first segment in a vertical direction falls within a range of the photoluminescent layer, and the projection portion of the second segment in the vertical direction It falls within the range of the photoluminescent layer. The direct type light-emitting device of claim 1, wherein an edge thickness of the lens is smaller than a distance between the peak point of the curved surface and an upper surface of the photoluminescent layer. The direct-lit light-emitting device of claim 1, wherein a distance between the peak point of the curved surface and an upper surface of the photoluminescent layer is greater than a thickness of the photoluminescent layer. The direct type light emitting device of claim 1, wherein the curved surface peak width is smaller than the width of the photoluminescent layer in the horizontal direction. The direct-type light-emitting device of claim 1, wherein the curved surface peak width is greater than a width of the photoluminescent layer in the horizontal direction. The direct-lit light-emitting device of claim 1, wherein a width of the photoluminescent layer in the horizontal direction is greater than or equal to 1.2 times and less than a width of a light-emitting surface of the light-emitting diode unit in the horizontal direction. Or equal to 5.2 times the width of the light emitting surface of the light emitting diode unit in the horizontal direction. The direct-lit light-emitting device of claim 1, wherein a width of the light-emitting surface of the light-emitting diode unit in the horizontal direction is smaller than a peak width of the curved surface. The direct-lit light-emitting device of claim 1, wherein the photoluminescent layer and the light-emitting diode unit are separated by an air layer. The direct-lit light-emitting device of claim 13, wherein the distance between the photoluminescent layer and the light-emitting diode unit is less than 0.5 mm. The direct-lit light-emitting device of claim 1, wherein the photoluminescent layer comprises a quantum dot photoluminescent layer. The direct type light emitting device of claim 1, wherein the light emitting diode unit comprises a blue light emitting diode unit. A display comprising: the direct type light emitting device according to any one of claims 1 to 18; and a display panel disposed on the direct type light emitting device, wherein the direct type light emitting device comprises a backlight module. The display device of claim 17, further comprising a diffusion sheet disposed between the direct type illumination device and the display panel. The display device of claim 17, further comprising a light regulating film disposed on the lens.