Patent Publication Number: US-2017370544-A1

Title: Primary optics light source with rectangular light pattern

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This non-provisional application claims priority under 35 U.S.C. §119(a) on Patent Application No(s). 105119903 filed in Taiwan, R.O.C. on Jun. 24, 2016, the entire contents of which are hereby incorporated by reference. 
     FIELD OF THE INVENTION 
     The present invention relates to the field of light emitting diodes (LEDs), and more particularly to a primary optics light source capable of projecting a rectangular light pattern in the primary optics. 
     BACKGROUND OF THE INVENTION 
     1. Description of the Related Art 
     Light emitting diode (LED) with the advantages of excellent color rendering and light emission efficiency has become a main light source for various different lamps. At present, a general LED just has a basic light dispersion capability after it is packaged. When it is necessary to form an LED light source with a specific light pattern, one or more optical elements such lenses or mirrors must be used, and the optical light reflection feature is used to emit lights with various illumination light patterns according to the LED light source, and such design of optical elements used for purposes other than the LED light source is generally called as “secondary optics design”. In addition to the lenses and mirrors, a common lamp housing design also falls in the category of secondary optics design. 
     To ensure the safety of driving, an automobile lamp must be in compliance with related laws and regulations on its brightness, angle of illumination, and light pattern of illumination. If an LED light source is applied in the field of automobile lamps, and the required light pattern is in a rectangular shape, most manufacturers adopt the secondary optics technology to design the automobile lamps due to the light output limitation of the LED light source. For example, a lens is added to the luminous light path of the LED to gather light and adjust the light pattern projected to the outside, so as to improve the illumination brightness of the LED and meet the light pattern requirement. 
     To adjust the light pattern from a scattered form into a rectangular form after the light passes the light through the lens of the lamp, the whole structural design of the lamp must take various complicated control factors into consideration, and thus increasing the level of inconvenience and difficulty of the design. In addition, the dimensions and specifications of the lamp various according to different models of motor vehicles. Therefore, finding a method of stably providing the required light pattern for different dimensions and specifications of the LED light source of motor vehicles and simplifying the structural design of the lamp demands immediate attentions and feasible solutions. Therefore, the inventor of the present invention bases on the idea of LED packaging technology of a light source to provide a primary optics light source with a rectangular light pattern to simplify the structure of the lamp and lowering the design and production costs of the lamp. 
     2. Summary of the Invention 
     Therefore, it is a primary objective of the present invention to provide a primary optics light source with a rectangular light pattern, and the primary optics light source is capable of directly forming a rectangular illumination light pattern when the light source is lit to achieve the effects of simplifying the structure of a lamp and lowing the installation and development costs. 
     To achieve the aforementioned and other objectives, the present invention discloses a primary optics light source with a rectangular light pattern in a preferred embodiment, the primary optics light source comprises a substrate, an LED chip and an encapsulated package, wherein the LED chip is installed at the substrate, and the encapsulated package covers the LED chip to fix it to the substrate, characterized in that a pair of first bent sections, a pair of second bent sections and a top section are sequentially arranged from the substrate and on the cross-section of the encapsulated package in the x-axis, and the first bent sections are disposed opposite to each other and extended from the substrate to couple with the second bent section, and the second bent sections are also disposed opposite to each other and coupled to an end of the top section, and the pair of first bent sections, the pair of second bent sections and the top section are all arc shaped, and the cross-section of the encapsulated package in the y-axis is arc shaped, thereby a light of the LED chip is emitted to the outside through the encapsulated package to form a rectangular light pattern; wherein the x-axis and the y-axis are perpendicular to each other, and a plane included between the x-axis and the y-axis is parallel to a plane of the substrate provided for installing the LED chip. Therefore, the primary optics light source can be lit through the encapsulated package to directly form the required rectangular light pattern without using the remaining optical elements for a secondary optics design. 
     Preferably, when the LED chip has a size of 55 mil, the rectangular light pattern has an aspect ratio falling within a range of 3.6:1-3.9:1; and when the LED chip has a size of 38 mil, the rectangular light pattern has an aspect ratio falling within a range of 5.45:1-5.75:1. 
     Before the encapsulated package is combined with the substrate, the substrate includes an adhesive for improving the bonding strength between the encapsulated package and the substrate. Preferably, the encapsulated package is made of silicone to provide excellent packaging and light transmission performance. 
     In another preferred embodiment, the present invention further discloses a primary optics light source with a rectangular light pattern including a substrate, an LED chip and an encapsulated package, and the LED chip is installed to the substrate, and the encapsulated package covers the LED chip to fix the LED chip to the substrate, and the invention is characterized in that a pair of first bent sections, a pair of second bent sections and a top section are sequentially arranged from the substrate and on a cross-section of the encapsulated package in the x-axis, and the first bent sections are disposed opposite to each other and extended from the substrate to couple with the second bent section, and the second bent sections are also disposed opposite to each other and coupled to an end of the top section, and the pair of first bent sections, the pair of second bent sections and the top section are all arc shaped, and a pair of third bent sections and an arc section are disposed on a cross-section of the encapsulated package in the y-axis, and the pair of third bent sections are disposed opposite to each other and extended from the substrate to couple with both ends of the arc section respectively, and the pair of third bent sections are perpendicular to the substrate, thereby a light of the LED chip is emitted to the outside through the encapsulated package to form a rectangular light pattern; wherein the x-axis and the y-axis are perpendicular to each other, and a plane included between the x-axis and the y-axis is parallel to a plane of the substrate provided for installing the LED chip. Therefore, the primary optics light source can be lit through the encapsulated package to directly form the required rectangular light pattern without using the remaining optical elements for a secondary optics design. 
     Similarly, when the LED chip has a size of 55 mil, the rectangular light pattern has an aspect ratio falling within a range of 3.6:1-3.9:1; and when the LED chip has a size of 38 mil, the rectangular light pattern has an aspect ratio falling within a range of 5.45:1-5.75:1. 
     Before the encapsulated package is combined with the substrate, the substrate includes an adhesive for improving the bonding strength between the encapsulated package and the substrate. Preferably, the encapsulated package is made of silicone to provide excellent packaging and light transmission performance. 
     In summation, the primary optics light source of the present invention is capable of directly obtaining a rectangular illumination light pattern in the primary optics design without requiring a secondary optics design to improving the application performance of the light source, so that the automotive lamp may skip the complicated structural design of the lamp and reduce the quantity of optical elements used, so as to reduce the total volume of the lamp. With the encapsulated package, the light emitted to the outside through the LED chip can be adjusted effectively to directly form the rectangular light pattern and maintain an excellent light output quality. In addition, the encapsulated package still maintain the rectangular light pattern of the primary optics light source and the same aspect ratio of the rectangular light pattern under the conditions of changing the proportion of its size or changing the specification of the LED chip. In addition, if the length of the encapsulated package is reduced in the y-axis, the rectangular light pattern of the primary optics light source will not be changed or affected. Therefore, the present invention improves the inconvenience of the light source of the conventional automotive lamp that requires a secondary optics design to form a specific light pattern, and thus the present invention further has the effect of lowering the design and development cost of the automotive lamp. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a first preferred embodiment of the present invention; 
         FIG. 2  is a cross-sectional view of the first preferred embodiment of the present invention along the x-axis; 
         FIG. 3  is a cross-sectional view of the first preferred embodiment of the present invention along the y-axis; 
         FIG. 4  shows a first light distribution curve of the first preferred embodiment of the present invention; 
         FIG. 5  shows a second light distribution curve of the first preferred embodiment of the present invention; 
         FIG. 6  is a schematic view showing an application of the first preferred embodiment of the present invention; 
         FIG. 7  is a perspective view of a second preferred embodiment of the present invention; 
         FIG. 8  is a cross-sectional view of the second preferred embodiment of the present invention along the x-axis; 
         FIG. 9  is a cross-sectional view of the second preferred embodiment of the present invention along the y-axis. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The above and other objects, features and advantages of this disclosure will become apparent from the following detailed description taken with the accompanying drawings. 
     To simplify the structural design of the automotive lamp effectively, the inventor of the present invention applied the concept of the optical design of the LED light source to form a rectangular illumination light pattern when the LED light source is lit. With reference to  FIGS. 1 to 6  for a perspective view, a cross-sectional view in the x-axis, a cross-sectional view in the y-axis, a first light distribution curve, a second light distribution curve, and a schematic view of an application of a primary optics light source with a rectangular light pattern in accordance with the first preferred embodiment of the present invention respectively, the primary optics light source with a rectangular light pattern  1  comprise a substrate  10 , an LED chip  11  and an encapsulated package  12 , and the LED chip  11  is installed on a surface  101  of the substrate  10 , and the encapsulated package  12  covers the LED chip  11  to fix the LED chip  11  to the substrate  10 . 
     The primary optics light source  1  is characterized in that a pair of first bent sections  121 , a pair of second bent sections  122  and a top section  123  are sequentially arranged from the substrate  10  and on a cross-section of the encapsulated package  12  in the x-axis, and the first bent sections  121  are disposed opposite to each other and extended from the substrate  10  to couple the second bent section  122 , and the second bent sections  122  are also disposed opposite to each other and coupled to an end of the top section  123 , and the pair of first bent sections  121 , the pair of second bent sections  122  and the top section  123  are all arc shaped as shown in  FIG. 2 . An arc section is disposed on a cross-section of the encapsulated package  12  in the y-axis. Preferably, both ends of the arc section  124  are coupled to the substrate  10 , so that the cross-section of the encapsulated package  12  in the y-axis is in an arc shape as shown in  FIG. 3 . Therefore, a rectangular light pattern A is formed after a light of the LED chip  11  is emitted to the outside through the encapsulated package  12 . Wherein, the x-axis and the y-axis are perpendicular to each other, and a plane included between the x-axis and the y-axis is parallel to a plane of the substrate  10  provided for installing the LED chip  11 . Specifically, the LED chip  11  is fixed onto a surface  101  of the substrate  10 , and the LED chip  11  acts as the origin, and the axial direction parallel to a first side  1011  of the surface  101  is the x-axis, and the axial direction of a second side  1012  of the surface  101  is the y-axis. The light output direction of the primary optics light source  1  is the z-axis perpendicular to the x-axis and the y-axis simultaneously, and the whole encapsulated package  12  is tapered along the z-axis. 
     Preferably, the encapsulated package  12  is made of silicone to achieve the effects of packaging the LED chip  11  conveniently, outputting a light, and adjusting the light pattern of the outputted light effectively. To provide a better bonding strength between the encapsulated package  12  and the substrate  10 , an adhesive is coated onto the substrate  10  before the encapsulated package  12  is combined with the substrate  10 , and the adhesive is provided for enhancing the fixing force between the encapsulated package  12  and the substrate  10 . 
     In  FIG. 4 , when the inventor of the present invention adopts an LED chip  11  with a size of 55 mil and the encapsulated package  12  in the aforementioned shape, experimental results show that after a light of the LED chip  11  is outputted through the encapsulated package  12 , the rectangular light pattern A of the primary optics light source  1  has an aspect ratio falling within a range of 3.6:1-3.9:1, and further measurements show that the abduction angle range of a plane of the polar coordinate C0-C180 of the rectangular light pattern A is approximately equal to 150 degrees, and the abduction angle range of a plane of the polar coordinate C90-C270 is approximately equal to 38.5 degrees, such that the rectangular light pattern A has an aspect ratio of 3.9:1 which is in compliance with the aforementioned range. In  FIG. 5 , the inventor of the present invention adopts another LED chip  11  with a size of 38 mil and the encapsulated package  12  with a shape matching the aforementioned shape, and experimental results show that the rectangular light pattern A of the primary optics light source  1  formed after a light of the LED chip  11  is outputted through the encapsulated package  12  has an aspect ratio falling within a range of 5.45:1-5.75:1, and further measurements show that the abduction angle range of a plane of the polar coordinate C0-C180 of the rectangular light pattern A is approximately equal to 142 degrees, and the abduction angle range of a plane of the polar coordinate C90-C270 of the rectangular light pattern A is approximately equal to 25 degrees, so that the rectangular light pattern A has an aspect ratio of 5.68:1 which is in compliance with the aforementioned range. With reference to  FIG. 6  for the schematic view of a rectangular light pattern A formed and projected from the primary optics light source  1  after the primary optics light source  1  is driven. The primary optics light source  1  outputs light in the z-axis, and the formed rectangular light pattern A has an aspect ratio substantially equal to 4:1. 
     Since the practical applications of the primary optics light source  1  are limited by special optical requirements or the requirements for applying the automotive lamp, therefore the specification of the LED chip  11  is also limited or specified by the foregoing contents. Even if the specification of the LED chip  11  is changed, the encapsulated package  12  is capable of maintaining the rectangular shape of the light pattern projected from the primary optics light source  1  to comply with the application requirements, so as to achieve the effect of providing simpler and easier elements for the lamp design. In addition, the size of the encapsulated package  12  may be increased or decrease in equal proportions according to the aforementioned shape in order to maintain the light pattern projected from the primary optics light source  1  in the rectangular shape. Obviously, the primary optics light source  1  of the present invention has excellent adjustability. After the size of the encapsulated package  12  is changed in equal proportions the rectangular light pattern still can be provided. 
     With reference to  FIGS. 7, 8 and 9  for a perspective view, a cross-sectional view in the x-axis, and a cross-sectional view in the y-axis of the second preferred embodiment of the present invention respectively, the size of the encapsulated package  12  may be limited in actual applications of the primary optics light source  1  to cope with various different automotive lamps. Even if the primary optics light source  1  of the present invention is applied to an automotive lamp with a narrow installation space, both ends of the encapsulated package  12  may be reduced slightly to decrease the total length along the y-axis without affecting light pattern projected from the primary optics light source. In this preferred embodiment, a pair of first bent sections  121 , a pair of second bent sections  122 , and a top section  123  are sequentially arranged from the substrate  10  and on a cross-section of the encapsulated package  12  in the x-axis, and the configuration is the same as that of the previous preferred embodiment, and thus will not be repeated. When it is necessary to reduce the length of the encapsulated package  12  in the y-axis, both ends of the encapsulated package  12  are removed, so that the cross-section of the encapsulated package  12  in the y-axis has a pair of third bent sections  124  and an arc section  125 , and the pair of third bent sections  124  are disposed opposite to each other and extended from the substrate  10  to couple with both ends of the arc section  125  respectively, and the pair of third bent sections  124  are perpendicular to the substrate  10  as shown in  FIG. 9 . In this preferred embodiment, the definitions of the x-axis and the y-axis are also the same as that of the previous preferred embodiment, and the x-axis and the y-axis are perpendicular to each other, and a plane included between the x-axis and the y-axis is parallel to a plane of the substrate  10  provided for installing the LED chip  12 . Specifically, the LED chip  11  is installed on a surface  101  of the substrate  10 , and the LED chip  11  acts as the origin, and the x-axis is parallel to a first side  1011  of the surface  101 , and the y-axis is parallel to a second side  1012  of the surface  101 . 
     Similarly, when an LED chip  11  with a size of 55 mil is used, the measured rectangular light pattern of the primary optics light source  1  has an aspect ratio falling within a range of 2.25:1-2.55:1. When an LED chip  11  with a size of 38 mil is used, the measured rectangular light pattern of the primary optics light source  1  has an aspect ratio falling within a range of 3.5:1-3.8:1. Therefore, the size of encapsulated package  12  of the primary optics light source  1  may be increased or decreased in equal proportions according to the previous preferred embodiment, or the length of the encapsulated package  12  in the y-axis may be changed to comply with the different specifications and requirements of various automotive lamps, and maintained the projected light pattern in a rectangular shape effectively. In addition, the fixing force between the encapsulated package  12  and the substrate  10  may be enhanced. Before the encapsulated package  12  is combined with the substrate  10 , an adhesive is coated onto the substrate  10  to improve the bonding strength between the encapsulated package  12  and the substrate  10 , and the encapsulated package  12  may be made of silicone to achieve the effects of light transmission and package protection. 
     In summation of the description above, the primary optics light source  1  of the present invention is capable of directly forming a rectangular light pattern projected from a primary optics light source without requiring a further secondary optics design to achieve the effects of improving the application performance of the light source, skipping the complicated structure design of the automotive lamp, and reducing the using quantity of other optical elements to reduce the total volume of the lamp. With the special stylish appearance of the encapsulated package  12 , the light emitted from the LED chip  11  can be adjusted effectively to form the rectangular light pattern A directly and maintain an excellent light output quality. To cope with the installation environment of the primary optics light source  1 , the shape of the rectangular light pattern A of the primary optics light source  1  and the same aspect ratio of the rectangular light pattern A can still be maintained when the size of the encapsulated package  12  is increased or decreased, or the specification of the LED chip  11  is changed. In a special automotive lamp installation environment, such as a very narrow space for installing an automotive lamp of the primary optics light source  1 , the length of the encapsulated package  12  in the y-axis may be reduced, so that the shape of the rectangular light pattern A projected from the primary optics light source  1  will not be changed or affected. Therefore, the present invention improves the inconvenience of the conventional automotive lamp that requires a secondary optics design to form the specific light pattern and the invention has the effect of lowering the design and development costs of the automotive lamp.