TECHNICAL FIELD

The present disclosure relates to a Light Emitting Diode (LED) lighting system for lighting a space, more particularly, the present disclosure relates to a Total Internal Reflection (TIR) lens unit for an LED lighting system, capable of enabling the collimation of light emitted from a plurality of LED units, at a substantially uniform beam angle, independent of the type of LED units employed therein.

BACKGROUND

This section is intended to provide information relating to the field of the invention and thus, any approach or functionality described below should not be assumed to be qualified as prior art merely by its inclusion in this section.

Light Emitting Diode (LED) lighting systems are commonly known in the lighting industry to illuminate a desired space or room. The LED lighting systems may be any of, but not limited to, a concealed lighting system, a wall mounted lighting system, and an anchor mounted lighting system. The LED lighting system commonly comprises a housing unit capable of housing and supporting the lighting unit, wherein the lighting unit is capable of emitting light in a desired space or room.

The housing unit of the LED lighting system further comprises an upper housing member, a lower housing member and a gasket therebetween to seal the upper housing member with the lower housing member. Further, the upper housing member is employed for housing the lighting unit therein, whereas the lower housing member is employed to cover the lighting unit positioned within the upper housing member. The lower housing member further defines a cavity for positioning of a transparent glass member. The upper housing member is attached to a mounting bracket on a rear side thereof, for fixing of the LED lighting system to one of a ceiling, a wall, and an anchor. Each of the upper housing member and the lower housing member define threaded holes on its periphery for allowing fastening means to pass therethrough.

The lighting unit of the LED lighting system comprises a plurality of LED units to emit a beam of light through a plurality of lens members for dispersion of light. The lighting unit further comprises a printed circuit board to electrically connect the components of the lighting unit thereto. Typically, each of the plurality of LED units are positioned within each of the plurality of lens members. The LED units selected from any one of a group of LED packages consisting of 3030 module, 5730 module, 5830 module, 5050 module, 2835 module, 3528 module, 3020 module, 3014 module, 7020 module, 4014 module, 3535 module, 3258 module and the like.

However, at a time, the lens member known in the art is capable of accommodating the plurality of LED units of the type of only one of the aforementioned LED packages to collimate a beam of light at a defined output beam angle. Moreover, the plurality of LED units from each of the above- mentioned type of LED package when placed below the same lens member, results in a relatively different level of collimation thereof, i.e., relatively different output beam angle. Further, the conventional lens member is capable of collimating a beam of light at an output beam angle in the range of 30 degrees to 60 degrees only. However, the conventional lens member fails to collimate light at a uniform beam angle of less than 30 degrees. 'Collimation' refers to a beam of light having substantially parallel rays, which allows the light to spread minimally as the light propagates.

Therefore, there is a well felt need to provide for an annular lens unit for an LED lighting system, capable of collimating a beam of light emitted from a plurality of LED units, at a substantially uniform beam angle of less than 30 degrees, independent of the type of LED units employed therein. SUMMARY OF THE INVENTION

This section is intended to introduce certain objects of the disclosed method and system in a simplified form and is not intended to identify the key advantages or features of the present disclosure.

The present disclosure relates to a total internal reflection (TIR) lens unit [200] for an LED lighting system [100], wherein the TIR lens unit [200] is employed to collimate light at a substantially uniform beam angle. Notably, the total internal reflection (TIR) lens unit [200] comprises a plurality of TIR lens members [202] , such that each of the plurality of TIR lens members [202] defines an external annular parabolic TIR portion [204] including an annular top cavity [206] with an outer convex surface [208] defining a radius of curvature (R); and an inner cylindrical reflector portion [210] including a top cavity, coaxially positioned within the external annular parabolic TIR portion [204]; wherein, the radius of curvature (R) is in the range of -3.0 millimeters to 8 millimeters, for enabling the collimation of light emitted from the plurality of LED units at a substantially uniform beam angle between 10 degrees and 30 degrees. With such an arrangement, the TIR lens unit [200] is capable of collimating the light at a substantially uniform beam angle in the range of 10 degrees to 30 degrees, independent of the type of LED units [106] employed therein.

BRIEF DESCRIPTION OF DRAWINGS

In order to explain the technical solution in the embodiments of the present application more clearly, the drawings used in the description of the embodiments will be briefly introduced below. It is obvious that the drawings in the following description are only some embodiments of the application. For those skilled in the art, without any creative work, other drawings can be obtained based on these drawings.

FIG. 1 shows an exploded view of an LED lighting system, illustrating various components comprised therein, in accordance with the concepts of the present invention.

FIG. 2 shows a perspective view of a TIR lens unit for the LED lighting system, in accordance with the concepts of the present invention.

FIG. 3 is a sectional view of the TIR lens unit for the LED lighting system, in accordance with the concepts of the present invention.

FIG. 4 shows a graphical representation of constant collimation of light with change in the radius of curvature (R), in accordance with the concepts of the present disclosure.

DETAILED DESCRIPTION

In the following description, for the purposes of explanation, various specific details are set forth in order to provide a thorough understanding of embodiments of the present invention. It will be apparent, however, that embodiments of the present invention may be practiced without these specific details. Several features described hereafter can each be used independently of one another or with any combination of other features. An individual feature may not address any of the problems discussed above or might address only one of the problems discussed above. Some of the problems discussed above might not be fully addressed by any of the features described herein. Exemplified embodiments of the present invention are described below, as illustrated in various drawings in which like reference numerals refer to the same parts throughout the different drawings.

The embodiments of the present invention relate to a Total internal reflection (TIR) lens unit [200] for a Light Emitting Diode (LED) lighting system [100], capable of collimating light emitted from a plurality of LED units [106] at a substantially uniform beam angle, independent of the type of LED units [106] employed therein.

FIG. 1 shows an exploded view of the LED lighting system [100], in accordance with the concepts of the present invention. FIG. 2 shows a perspective view of the TIR lens unit [200] for the LED lighting system [100], in accordance with the concepts of the present invention. FIG. 3 is a sectional view of the TIR lens unit [200] for the LED lighting system [100], in accordance with the concepts of the present invention. FIG. 1, 2, and 3 are to be viewed in conjunction with one another, in order to completely understand the concepts of the present disclosure. The LED lighting system [100] comprises a lighting unit [102] for emitting light, a housing unit [110] to house and support the lighting unit [102] therein, and a TIR lens unit [200] positioned on the lighting unit [102] such that the TIR lens unit [200] enables the collimation of light emitted therefrom at a substantially uniform beam angle. The structure and arrangement of various components of the LED lighting system [100] will be explained hereinafter in detail.

HOUSING UNIT

The housing unit [110] of the LED lighting system [100] employs an upper housing member [112], a lower housing member [114], and a gasket [116] disposed therebetween to seal the upper housing member [112] with the lower housing member [114], Further, the upper housing member [112] defines a cavity for housing and supporting the lighting unit [102] therein, and a mounting provision [120] on a rear side of the upper housing member [112], to affix a mounting bracket thereto. The mounting bracket is employed for mounting the LED lighting system [100] to one of a ceiling, a wall, an anchor and the like. The lower housing member [114] defines a cavity for positioning a transparent glass member [122] therein, such that the transparent glass member [122] allows the beam of light emitted from the lighting unit [102], to pass therethrough.

Moreover, the upper housing member [112] defines an inner peripheral cavity [118] on the inner periphery thereof, such that the inner peripheral cavity [118] is adapted to receive the gasket [116] therein. Further, each of the upper housing member [112] and the lower housing member [114] define a plurality of threaded holes [124] positioned on the inner periphery of the housing unit [110], for allowing screws to pass therethrough.

LIGHTING UNIT

The lighting unit [102] comprises a printed circuit board (PCB) [104], a surge protection device (SPD) [108] and a plurality of LED units [106], The PCB [104] is employed in the lighting unit [102] to support and electrically connect the plurality of LED units [106] and the SPD [108] thereon, through conductive pathways, tracks or signal traces etched from copper sheets laminated onto a non-conductive substrate. Further, the SPD [108] is electrically connected to the PCB [104] to provide protection against failure of the LED lighting system [100] due to conditions such as, but not limited to overvoltage, undervoltage, short- circuit overcurrent, and current leakage, and to provide the required current thereto.

The plurality of LED units [106] is further annularly embedded on the PCB [104], such that the plurality of LED units [106] is in the form of one or more annular strips of LED units [106], for enabling the positioning of a plurality of TIR lens members [202] of the TIR lens unit [200] thereon. Notably, the one or more annular strips of LED units [106] are symmetrically embedded across a length and a width of the PCB [104], further enabling the positioning of each of the plurality of TIR lens members [202] of the TIR lens unit [200] on each of the one or more annular strips of LED units [106], The plurality of LED units [106] can be selected from a group consisting of 3030, 5730, 5830, 5050, 2835, 3528, 3020, 3014, 7020, 4014, 3535, and 3258 type of LED package or any combination thereof.

TOTAL INTERNAL REFLECTION (TIR) LENS UNIT

The TIR lens unit [200] comprises a plurality of TIR lens members [202] for collimation of the beam of light emitted from the one or more annular strips of the LED units [106], at a substantially uniform beam angle between 10 degrees and 30 degrees. Further, each of the plurality of TIR lens members [202] define an external annular parabolic TIR portion [204] including an annular top cavity [206] with an outer convex surface [208] defining a radius of curvature (R), and an inner cylindrical reflector portion [210] including a top cavity, coaxially positioned within the external annular parabolic TIR portion [204],

The radius of curvature (R) of the annular top cavity [206] of the TIR lens member [202] of the TIR lens unit [200] is in the range of -3.0 millimeters to 8.0 millimeters, for enabling the collimation of light emitted from a plurality of LED units [106], at a substantially uniform beam angle between 10 degrees and 30 degrees. While each of the plurality of the TIR lens members [202] is positioned on each of the one or more annular strips of the LED units [106], the annular top cavity [206] of each of the plurality of TIR lens members [202] receives each of the one or more annular strips of the LED units [106] therein, such that the light emitted from the one or more annular strips of the LED units [106] is collimated at a substantially uniform beam angle being any of 10 degrees, 25 degrees and 30 degrees. The structure of various embodiments of the TIR lens members [202], in accordance with the concepts of the present disclosure, will be discussed hereinafter in detail.

In a first embodiment, the radius of curvature (R) of the annular top cavity [206] defined on the external annular parabolic TIR portion [204] of each of the plurality of the TIR lens members [202], is in a range of -3.0 millimeters to -1.75 millimeters. This embodiment is capable of enabling the collimation of light emitted from the plurality of LED units [106], at a substantially uniform beam angle of 15 degrees, independent of the type of the LED units [106] employed therein. Further, the plurality of LED units [106] employed to emit light through the TIR lens member [202] of the present embodiment, may be selected from a group consisting of 3030, 5730, 5830, 5050, 2835, 3528, 3020, 3014, 7020, 4014, 3535, 3258 type of LED package or any combination thereof.

In a second embodiment, the radius of curvature (R) of the annular top cavity [206] defined on the external annular parabolic TIR portion [204] of each of the plurality of the TIR lens member [202] is in the range of 6.5 millimeters to 8.0 millimeters. The present embodiment is capable of enabling the collimation of light emitted from the plurality of LED units [106], at a substantially uniform beam angle of 25 degrees, independent of the type of the LED units [106] employed therein. Further, the plurality of LED units [106] employed to emit light through the TIR lens member [202] of the present embodiment, may be selected from a group consisting of 3030, 5730, 5830, 5050, 2835, 3528, 3020, 3014, 7020, 4014, 3535, 3258 type of LED package or any combination thereof.

In yet another embodiment, the radius of curvature (R) of the annular top cavity [206] defined on the external annular parabolic TIR portion [204] of each of the plurality of the TIR lens member [202] is in the range of 2.1 millimeters to 4.0 millimeters. This embodiment is capable of enabling the collimation of light emitted from the plurality of LED units [106], at a substantially uniform beam angle of 30 degrees, independent of the type of the LED units [106] employed therein. Further, the plurality of LED units [106] employed to emit light through the TIR lens member [202] of the present embodiment, may be selected from a group consisting of 3030, 5730, 5830, 5050, 2835, 3528, 3020, 3014, 7020, 4014, 3535, 3258 type of LED package or any combination thereof.

EXAMPLE

Following examples are given by way of illustration, and therefore, should not be construed to limit the scope of this invention.

The variation in the radius of curvature (R) of the annular top cavity [206] defined on the external annular parabolic TIR portion [204] of the TIR lens members [202] results in the collimation of a beam of light passing therethrough, at a substantially uniform beam angle of 30 degrees, independent of the type of LED units [106] employed therein, as is apparent from below given example. FIG. 4 shows a graphical representation of the constant collimation of light with change in the radius of curvature (R) of the annular top cavity [206] of the TIR lens member [202], in accordance with the example disclosed hereunder. The below given example is to be read in conjunction with FIG. 4, in order to properly understand the concepts of the present disclosure.

An experiment was performed by placing a plurality of LED units [106] selected from the group of 2835 and 3030 type of LED package, in the form of three annular strips of LED units [106] within the annular top cavity [206] of the external annular parabolic TIR portion [204] of each of the three TIR lens members [202] having different radius of curvature (R) of the annular top cavity [206] thereof. The radius of curvatures of the respective TIR lens members [202] are disclosed hereunder:

TIR LENS MEMBER 1: Radius of Curvature (Rl) = 2.8 millimeters.

TIR LENS MEMBER 2: Radius of Curvature (R2) = 3.0 millimeters.

TIR LENS MEMBER 3: Radius of Curvature (R3) = 3.2 millimeters. wherein R2 is taken as a standard reference, and Rl and R3 are varied in accordance with R2, such that:

Curve Change forTIR LENS MEMBER 1 = - 0.2 mm.

Curve Change forTIR LENS MEMBER 2 = 0 mm.

Curve Change forTIR LENS MEMBER 3 = + 0.2 mm.

With such an arrangement, a substantially uniform beam angle of 30 degrees (+ 20% tolerance) is achieved.

Table 1 shows the output beam angles for different type of LED units [106] employed in each of the three TIR lens members [202] with different change in the radius of curvature.

Table 1:

ASSEMBLY

In assembly of the LED lighting system [100], in accordance with the present disclosure, various components of the LED lighting system [100] are assembled together in the following manner:

First step: The one or more of the annular strips of LED units [106] are symmetrically embedded across the length and the width of the PCB [104],

Second step: The SPD [108] is electrically connected onto the PCB [104] for protection of the LED lighting system [100], against overcurrent, overvoltage, undervoltage, short circuit, current leakage, and the like. Thus, this step completes the assembly of the lighting unit [102],

Third step: Each of the plurality of TIR lens members [202] of the TIR lens unit [200] is then positioned on each of the one or more annular strips of LED units [106], such that each of the one or more annular strip of LED units [106] is covered within the annular top cavity [206] defined on the external annular parabolic TIR portion [204] of each of the plurality of TIR lens members [202],

Fourth step: The lighting unit [102] is positioned within the cavity of the upper housing member [112] and is fastened thereto by means of screws.

Fifth step: The gasket [116] is thereafter positioned within the inner peripheral cavity [118] of the upper housing member [112], whereafter the lower housing member [114] is positioned on top of the upper housing member [112] to engage with the gasket [116], enabling the sealing the assembly in a fluid-tight manner.

Sixth step: The lower housing member [114] is then attached with the upper housing member [112] by means of screws, across the threaded holes [124] on the inner periphery of each of the lower housing member [114] and the upper housing member [112], Thus, this arrangement completes the assembly of the LED lighting system [100],

Seventh/Final step: The LED lighting system [100], thus assembled, is then mounted on any of the ceiling, the wall, the anchor and the like, with the help of a mounting bracket capable of engaging and locking the mounting provision [120] of the upper housing member [112] with a desired mounting area.

With such an arrangement, the LED lighting system [100] comprising a TIR lens unit [200] is capable of collimating a beam of light emitted from the plurality of LED units [106] employed therein, at a substantially uniform beam angle between 10 degrees and 30 degrees, which was not possible with the existing LED lighting system. Further, the TIR lens unit [200] for the LED lighting system [100], in accordance with the concepts of the present disclosure, is capable of employing the plurality of LED units [106] selected from either one or any combination of 3030, 5730, 5830, 5050, 2835, 3528, 3020, 3014, 7020, 4014, 3535, 3258 type of LED packages, while maintaining a substantially uniform beam angle being one of 10 degrees, 25 degrees and 30 degrees.

While the preferred embodiments of the present invention have been described hereinabove, it should be understood that various changes, adaptations, and modifications may be made therein without departing from the spirit of the invention and the scope of the appended claims. It will be obvious to a person skilled in the art that the present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive.

LIST OF COMPONENTS

100 - LED lighting system

102 - Lighting Unit

104 - Printed circuit board

106 - LED units

108 - Surge Protection Device 110 - Housing Unit

112 - Upper Housing Member

114 - Lower Housing Member

116 - Gasket 118 - Inner Peripheral Cavity

120 - Mounting Provision

122 -Transparent glass member

124 -Threaded Holes

200 - Total Internal Reflection (TIR) lens unit 202 -TIR lens member

204 - External annular parabolic TIR portion

206 - Annular top cavity

208 - Outer convex surface

210 - Inner cylindrical reflector portion