JP2013196847A - Led lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lamp that emits light uniformly as a whole, when an LED is arranged on a substrate of a straight tube LED lamp.SOLUTION: An LED lamp is provided with a glass tube 56 (cylindrical tube), a substrate 52 which is a substrate 52 mounting an LED 51 and extends throughout the longitudinal direction of the glass tube 56 (cylindrical tube), a waveform diffusion reflection part 80 which is a diffusion reflection part 80 for reflecting light from the LED 51 and is formed on the circumference of the glass tube 56 (cylindrical tube) at the side of the substrate 52. As for the diffusion reflection part 80, the width in circumference direction varies throughout the longitudinal direction of the glass tube 56 (cylindrical tube), and the width W2 in the circumference direction of the diffusion reflection part 80 between the LEDs 51 is larger than the width W1 in the circumference direction of the diffusion reflection part 80 at the side of the LEDs 51.

Description

  The present invention relates to an LED lamp such as an LED (light emitting diode) lamp.

  When the LED is arranged on the substrate of the straight tube type LED lamp, the LED portion is bright and dark between the LEDs.

JP 2007-115595 A JP 2011-108424 A Japanese Patent Laying-Open No. 2005-074687 JP 2011-171104 A

  An object of the present invention is to provide a lamp that uniformly emits light as a whole when, for example, LEDs are arranged on a substrate of a straight tube type LED lamp.

The LED lamp according to the present invention is an LED lamp using a light emitting diode (LED).
A tube,
A substrate on which an LED is mounted, the substrate extending in the longitudinal direction of the tube,
A diffuse reflection part for reflecting light from the LED, and a diffuse reflection part formed on the peripheral surface of the tube on the side of the substrate;
The diffuse reflection portion has a circumferential width that changes over the longitudinal direction of the tube,
The circumferential width of the diffuse reflection portion between the LEDs is larger than the circumferential width of the diffuse reflection portion on the side of the LED.

  The diffuse reflection portion is characterized in that the width in the circumferential direction is changed over the longitudinal direction of the tube so as to reflect the light outside the light distribution angle of the LED out of the light from the LED. .

  The diffuse reflection portion is formed to the inner side of the position where the light with the light distribution angle of the LED and the tube tube intersect.

  The diffuse reflection part has a waveform shape.

The diffuse reflection part does not exist on the side of the LED,
The diffuse reflection part has a bowl shape or a mountain shape between LEDs.

The LED lamp according to the present invention is:
In an LED lamp using a light emitting diode (LED),
A tube,
A substrate on which an LED is mounted, the substrate extending in the longitudinal direction of the tube,
A diffuse reflection part that reflects light from an LED, the diffuse reflection part being formed on a side of the substrate over the longitudinal direction of the tube on the peripheral surface of the tube.

  The diffuse reflection portion is present only on one side of the substrate and is not present on the other side of the substrate.

The cylindrical tube has an opening that emits light,
The emission center direction of the LED is inclined with respect to the radial direction of the tube passing through the center of the opening.

  The angle α on the lamp emission direction side formed by the surface of the substrate and the line connecting the LED and the end of the diffuse reflection portion is less than 90 degrees.

The diffuse reflection portion extends on both sides of the substrate over the longitudinal direction of the tube,
The cylindrical tube has an opening for emitting light.

The angle at which the brightness is halved compared to the brightness of the optical axis of the LED is the light distribution angle h,
When the opening angle in the circumferential direction of the opening viewed from the light emission center of the LED is the light emission opening angle γ,
Light emitting aperture angle γ <light distribution angle h
It is characterized by being.

The angle at which the brightness is halved compared to the brightness of the optical axis of the LED is the light distribution angle h,
The opening angle in the circumferential direction of the opening viewed from the light emission center of the LED is the light emission opening angle γ,
When the opening angle in the circumferential direction of the opening viewed from the cross-sectional center O of the tube is the opening center angle Δ,
Light emitting aperture angle γ = opening center angle Δ <light distribution angle h
It is characterized by being.

The angle at which the brightness is halved compared to the brightness of the optical axis of the LED is the light distribution angle h,
When the opening angle in the circumferential direction of the opening viewed from the cross-sectional center O of the tube tube is the opening center angle Δ,
Opening center angle Δ = light distribution angle h
It is characterized by being.

The angle at which the brightness is halved compared to the brightness of the optical axis of the LED is the light distribution angle h,
When the opening angle in the circumferential direction of the opening viewed from the light emission center of the LED is the light emission opening angle γ,
Light emitting aperture angle γ = light distribution angle h−20 degrees ± 10%
It is characterized by being.

The opening angle in the circumferential direction of the opening as viewed from the cross-sectional center O of the tube is defined as the opening center angle Δ,
When the ratio of the opening width of the opening and the inner diameter of the glass tube is the opening ratio,
112.8 degrees ≦ opening center angle Δ <120 degrees 0.83 ≦ opening ratio <0.87
Or
110.2 degrees ≦ opening center angle Δ <120 degrees 0.82 ≦ opening ratio <0.87
It is characterized by being.

  The diffuse reflection part has a titanium oxide film formed on the inner surface or the outer surface of the tube.

  Since the LED lamp according to the present invention uses the light reflected by the diffuse reflection portion, uniform light emission can be provided.

FIG. 3 shows an LED lamp 50 according to the first embodiment. The figure which shows the AA longitudinal cross-section of the LED lamp 50 of Embodiment 1. FIG. FIG. 3 shows an LED lamp 50 according to the first embodiment. FIG. 3 shows an LED lamp 50 according to the first embodiment. FIG. 5 shows an LED lamp 50 according to a second embodiment. The figure which shows the AA longitudinal cross-section of the LED lamp 50 of Embodiment 2. FIG. The figure which shows the AA longitudinal cross-section of the LED lamp 50 of Embodiment 2. FIG. The figure which shows the AA longitudinal cross-section of the LED lamp 50 of Embodiment 2. FIG. FIG. 5 shows an LED lamp 50 according to a second embodiment. FIG. 5 shows an LED lamp 50 according to a second embodiment. FIG. 5 shows an LED lamp 50 according to a second embodiment. The figure which shows the AA longitudinal cross-section of the LED lamp 50 of Embodiment 3. FIG. The figure which shows the AA longitudinal cross-section of the LED lamp 50 of Embodiment 3. FIG. The figure which shows the AA longitudinal cross-section of the LED lamp 50 of Embodiment 3. FIG. The figure which shows the AA longitudinal cross-section of the LED lamp 50 of Embodiment 3. FIG. The figure which shows the AA longitudinal cross-section of the LED lamp 50 of Embodiment 3. FIG. The figure which shows the AA longitudinal cross-section of the LED lamp 50 of Embodiment 3. FIG. The figure which shows the AA longitudinal cross-section of the LED lamp 50 of Embodiment 3. FIG. FIG. 6 shows an LED lamp 50 according to a fourth embodiment. The figure which shows the AA longitudinal cross-section of the LED lamp 50 of Embodiment 4. FIG. The figure which shows the AA longitudinal cross-section of the LED lamp 50 of Embodiment 4. FIG.

Embodiment 1 FIG.
FIG. 1 is a diagram showing an LED lamp 50 according to the first embodiment.
The LED lamp 50 has a cylindrical glass tube 56. The glass tube 56 is a transparent straight tube type glass tube and is an example of a tube tube. The tube may not be a glass tube but may be a transparent or translucent resin tube.

  The LED lamp 50 has a structure in which dust cannot enter the lamp that impairs safety during use from the viewpoint of long-term use. That is, the glass tube 56 and the base 55 are bonded together, and the light emitting unit 60 is sealed.

The LED lamp 50 is a straight tube LED lamp system that cannot be permanently disassembled without losing its function.
The LED lamp 50 has a glass outer shell, has the same outer diameter as a commercially available fluorescent lamp, and does not deform the outer shape of the straight tube LED lamp from the shape of the fluorescent lamp.

The light emitting unit 60 includes a light emitting diode (LED 51), a substrate 52, and a heat sink 54.
The light emitting unit 60 is housed in the glass tube 56 and emits light. The light emitting unit 60 extends in the longitudinal direction of the glass tube 56.

The LED 51 is an example of a light source, and includes an LED (light emitting diode) alone or an LED module.
The substrate 52 has a plurality of LEDs 51 arranged and arranged uniformly.
In FIG. 1, the lamp emission center direction (also referred to as lamp emission direction) is the same as the LED emission center direction (also referred to as LED emission direction).
In FIG. 1, a line heading diagonally left and right from the LED 51 indicates a light beam in the longitudinal direction among light beams having an angle (light distribution angle h) at which the brightness is halved compared to the brightness of the optical axis (center). Yes.
In FIG. 1, a plurality of LEDs 51 are arranged in the longitudinal direction so that a light beam having a light distribution angle h (light beam in the longitudinal direction) intersects a light beam having a light distribution angle h (light beam in the longitudinal direction) of the adjacent LED 51 in front of the glass tube 56. Are arranged in a row.
The portion between the LEDs 51 and 51 is a portion where the brightness of the light beam of the LED 51 becomes weaker and darker. By crossing in front of each other, the light beam having a brightness of half or more is irradiated twice in the central portion between the LEDs 51. Thus, the central portion between the LEDs 51 is prevented from becoming dark.
If the distance between the adjacent LEDs 51 is increased, the central portion between the adjacent LEDs 51 becomes darker. It is preferable that the distance be equal to or less than the distance between the glass tubes 56 in the lamp emission direction.

  The heat sink 54 is made of a metal such as aluminum, and serves as a pedestal to which the substrate 52 is attached and a heat dissipation member.

There are a pair of caps 55 at both ends of the glass tube 56.
Each base 55 includes a pair of power supply terminals 58. The number and shape of the power supply terminals 58 are not limited to the drawing and may be other numbers or shapes.

  The pair of caps 55 covers both ends of the glass tube 56 and is fixed to both ends of the heat sink 54 of the light emitting unit 60.

A diffuse reflection part 80 is formed on the inner surface of the glass tube 56. The diffuse reflection unit 80 reflects light without transmitting light.
The effect of the diffuse reflection unit 80 is that when the diffuse reflection unit 80 is irradiated with light from a certain direction, the diffuse reflection unit 80 reflects the light while scattering the light to the surroundings. This is because uniform light emission can be obtained.
The width of the diffuse reflection unit 80 in FIG. 1 varies in the longitudinal direction, and the side of the upper end portion of the diffuse reflection unit 80 has a waveform. The width W1 of the diffuse reflector 80 on the side of the LED 51 is smaller than the width W2 of the diffuse reflector 80 between the LEDs 51.

  The width of the diffuse reflection unit 80 increases as the distance from the LED 51 increases, and decreases as the LED 51 approaches. By changing the width of the diffuse reflector 80, the amount of light reflected by the diffuse reflector 80 in the vicinity of the LED 51 can be reduced, and the amount of light reflected can be increased as the distance from the LED 51 increases, resulting in uniform light emission in the longitudinal direction. it can.

  The opening 85 is a window that emits light from the glass tube 56. The opening 85 provides an opening window in the longitudinal direction.

FIG. 2 is a partially omitted view showing an AA longitudinal section (a section taken along a plane perpendicular to the tube axis) of the LED lamp 50 of the first embodiment.
The diffuse reflection part 80 is a diffuse reflection film formed on the inner surface of the glass tube 56. The diffuse reflection film can be formed of a titanium oxide film. The diffuse reflection unit 80 generates diffused light by irregularly reflecting light.
The LED light emission direction is a radial direction (transverse orthogonal to the surface of the substrate 52) passing through the cross-sectional center O and the center of the surface of the substrate 52.

  The surface of the substrate 52 is mirror-finished or has a surface finish with high reflectivity. Alternatively, a diffuse reflection film may be formed on the surface of the substrate 52 with the same titanium oxide film as the diffuse reflection part 80.

  The diffuse reflection part 80 exists on both sides of the substrate 52. The light that passes through the opening 85 includes direct light that directly passes through the opening 85 from the LED 51 and reflected light that is diffusely reflected by the diffuse reflection parts 80 on both sides and passes through the opening 85. The direct light and the reflected light are combined to determine the lamp emission direction.

In an LED light distribution curve, an angle at which two points having the same luminous intensity are spread with respect to the optical axis (center) of the LED is called a beam angle. The beam angle is also simply called light distribution. An angle at which the brightness is halved compared to the brightness of the optical axis (center) is referred to as a light distribution angle h.
An intersection that extends the light distribution angle h of the LED 51 and intersects the inner surface of the glass tube 56 is hereinafter referred to as a position X.
Hereinafter, the distance between the end portions 81 of the diffuse reflection portion 80 is referred to as an opening width k. The opening width k is also the distance in the width direction of the opening 85.

As shown in FIG. 2, the opening 85 opens in the same range as the light distribution angle h of the LED 51. That is, the end 81 of the diffuse reflection unit 80 is the same as the position X, and is at the same angle as the light distribution angle h of the LED 51.
When the opening 85 is made larger than the light distribution angle h of the LED 51 (the area of the diffuse reflection unit 80 is reduced) and the diffuse reflection unit 80 covers up to an angle at which the brightness of light is less than half, Since the amount of diffusion by the reflector 80 is reduced, the uniformity may be reduced. In order to increase the diffusion amount and improve the uniformity, the opening angle in the circumferential direction of the opening 85 is preferably set to be equal to or smaller than the light distribution angle h of the LED 51.
That is, the diffuse reflection unit 80 reflects all of the light from the LED 51 at least outside the light distribution angle of the LED 51. Then, the diffuse reflection part 80 is formed to the inner side of the position where the light of the light distribution angle of the LED 51 and the glass tube 56 intersect, and the diffuse reflection part 80 diffuses and reflects light rays whose light brightness is more than half. desirable.
In addition, if the opening angle of the circumferential direction of the opening part 85 is made into the light distribution angle h of LED51 or less, the light distribution of LED lamp 50 will become narrow. If importance is placed on the light distribution of the LED lamp 50, the opening angle in the circumferential direction of the opening 85 may be brought close to the light distribution angle h of the LED 51. Furthermore, if importance is attached to the light distribution of the LED lamp 50, the opening angle in the circumferential direction of the opening 85 may be set to be equal to or larger than the light distribution angle h of the LED 51.

The light beam having the light distribution angle h of the LED 51 extends 360 degrees around the LED 51, and becomes conical when all the light beams having the light distribution angle h of the LED 51 are connected. The glass tube 56 has a cylindrical ring shape, and a line connecting the intersections of the conical light beam and the ring-shaped glass tube 56 is formed. Hereinafter, this line is referred to as an intersection curve.
As shown in FIG. 1, the intersection curve becomes a curve in the glass tube 56 around one LED 51. Moreover, the intersecting curve is a curve having the smallest width W1 in the glass tubes 56 on both sides just beside the LED 51.

The intersecting curves of the conical rays of the adjacent LEDs 51 and the annular glass tube 56 intersect between the adjacent LEDs 51.
When the two intersecting curves of the adjacent LEDs 51 intersect, that is, in the glass tube 56 at the center position of the adjacent LEDs 51, the width of the diffuse reflection portion 80 becomes the maximum width W2.
Thus, the end portion 81 of the diffuse reflection portion 80 forms a wavy line. Hereinafter, the line formed by the wavy end portion 81 is referred to as a light tube intersection line.

In FIG. 1, the light tube intersection line is formed on both sides of the substrate 52, and the light tube intersection line is a position where the opening 85 exists. That is, the opening 85 is formed within the range of the width of the two light tube intersection lines.
Conversely, the line up to (before) the light tube intersection line is a line where the end portion 81 of the diffuse reflection portion 80 exists. That is, the diffuse reflection part 80 is formed so as not to exceed the two light tube intersection lines from both sides of the substrate 52 toward the opening 85.
By doing so, the diffuse reflection unit 80 can diffuse and reflect all the light outside the light distribution angle h of the LED 51. Moreover, the opening part 85 can radiate | emit all the light within the light distribution angle h of LED51 as direct light.
In order to enhance the diffusion effect, the diffuse reflection part 80 may be advanced and the opening 85 narrowed while maintaining the shape of the light tube intersection line. Conversely, in order to increase the light distribution, it is only necessary to retract the diffuse reflection part 80 and widen the opening 85 while keeping the shape of the light tube intersection line.

*** Variation 1 ***
FIG. 3 is a view showing a vertical AA cross section of the LED lamp 50 of the first embodiment.
The difference from FIG. 1 is that the shape of the end portion 81 of the diffuse reflection portion 80 is not a waveform but a saddle shape or a round mountain shape.

*** Variation 2 ***
FIG. 4 is a diagram showing a vertical AA section of the LED lamp 50 according to the first embodiment.
The difference from FIG. 1 is that the shape of the end portion 81 of the diffuse reflection portion 80 is not a waveform but a sine curve shape or an uneven shape.

*** Variation 3 ***
The diffuse reflection portion 80 may be provided on the outer peripheral surface instead of the inner peripheral surface of the glass tube 56 (see FIG. 8 when the diffuse reflection portion 80 described later is only on one side).

*** Variation 4 ****
The shape of the end of the diffuse reflector 80 is not a waveform, and the diffuse reflector 80 is not formed on the side of the LED 51, and the diffuse reflector 80 includes a plurality of saddle-shaped reflectors formed at intervals. A plurality of semicircular reflecting portions may be formed. The shape of the diffuse reflector 80 may be a triangle, trapezoid, semi-ellipse, tongue, bell, dome, or the like (see FIGS. 9, 10, and 11 when the diffuse reflector 80 described later is only on one side). .

Embodiment 2. FIG.
Differences from the first embodiment will be described.
FIG. 5 is a diagram illustrating the LED lamp 50 according to the second embodiment.
Also in FIG. 5, the LEDs 51 are arranged in a line at equal intervals. In FIG. 5, the LEDs 51 are arranged more densely than in FIG. 1 of the first embodiment. The LEDs 51 may be arranged more densely.
FIG. 6 is a partially omitted view showing an AA longitudinal section (a section taken along a plane perpendicular to the tube axis) of the LED lamp 50 of the second embodiment.

The diffuse reflection part 80 exists only on one side of the substrate 52.
The shape of the diffuse reflection portion 80 is a band shape, and has a uniform width in the longitudinal direction.
The light of the LED 51 includes direct light that directly passes through the glass tube 56 and reflected light that is diffusely reflected by the diffuse reflection portion 80 on only one side. As a result, the lamp emission direction of the LED lamp 50 is an upper left direction in FIG.
That is, in FIGS. 5 and 6, the lamp emission center direction (the radial direction of the tube passing through the center of the opening 85) is different from the LED emission center direction.

In FIG. 6, the left side of the broken line L connecting the end portion 81 of the diffuse reflection portion 80 and the end portion of the light emitting portion 60 on the side where the diffuse reflection portion 80 is present (the end portion of the substrate 52 or the end portion of the heat sink 54) is Opening 85.
In FIG. 6, an upper left portion from the broken line L is an opening 85 that emits light, and a lower right portion from the broken line L is a light emitting reflection portion 86 that emits and reflects light.

In FIG. 6, the center angle (opening center angle) formed from the center O to both ends of the opening 85 is less than 180 degrees. The central angle (the central angle of the light emitting / reflecting part) formed from the center O to both ends of the light emitting / reflecting part 86 is greater than 180 degrees.
In FIG. 6, the central angle formed from the center O to both ends of the light emitting unit 60 (light emitting unit central angle) is smaller than the central angle formed from the center O to both ends of the diffuse reflecting unit 80 (diffuse reflecting unit central angle).

The central angle of the opening 85 + the central angle of the light emitting / reflecting part 86 = 360 degrees The central angle of the opening 85 <180 degrees The central angle of the light reflecting part 86> 180 degrees The central angle of the light emitting part <Diffusion reflection center angle

In FIG. 6, at least the diffuse reflection part 80 is formed to be larger than the LED light emission direction beyond the inner surface of the glass tube 56 in the LED light emission direction, and the diffuse reflection part 80 covers the front surface of the LED 51.
That is, the diffuse reflection unit 80 is formed from the right side surface of the LED substrate 52 along the right inner peripheral surface of the glass tube 56, and further the LED light emission direction is changed from right to left so that the diffuse reflection unit 80 covers the LED light emission direction. Formed beyond.
As a result, the angle α on the lamp emission direction side formed by the line connecting the LED 51 and the end of the diffuse reflection portion 80 (broken line M in FIG. 6) and the surface of the LED substrate 52 is an acute angle of less than 90 degrees. If the angle α is 90 degrees or more, the LED 51 is easily visible from the outside. Therefore, the angle α is preferably 80 degrees or less. If the angle α is too small, the opening 85 becomes narrow, so the angle α is preferably 60 degrees or more. The angle α is preferably 70 degrees.
Further, an angle β formed by a string connecting the both ends of the diffuse reflection portion 80 (broken line N in FIG. 6) and the surface of the LED substrate 52 is an acute angle of less than 90 degrees.

In this way, the LED substrate 52 is disposed at an acute angle with respect to the string of the diffuse reflector 80 (broken line N in FIG. 6), and the strong light from the front surface of the LED 51 (particularly, the light in the LED emission direction) is diffusely reflected. The uniform light thus obtained can be emitted from the light emission direction of the lamp.
In addition, since the LED substrate 52 is arranged at an acute angle with respect to the string of the diffuse reflector 80 (broken line N in FIG. 6), even if a human sees the lamp from the direction opposite to the lamp emission direction, the LED 51 emits strong light. Since it cannot be directly viewed, it is possible to provide an eye-friendly lamp.

If the diffuse reflection part 80 does not cover the LED light emission direction, the front surface of the LED 51 is exposed, so that strong light emission is emitted as it is, and the effect of irregular reflection cannot be obtained and uniform light cannot be obtained.
In addition, if the diffuse reflection part 80 does not cover the LED light emitting direction, a special lamp having a bright oblique side is obtained. However, depending on the use of the lamp, a special lamp having a bright oblique side may be useful. The diffuse reflection portion 80 may not cover the LED light emission direction, and the angle α may be larger than 90 degrees.

*** Variation 1 ***
FIG. 7 is a diagram showing a vertical AA section of the LED lamp 50 according to the second embodiment.
The difference from FIG. 6 is that the LED 51 and the substrate 52 are close to the diffuse reflector 80. Since the LED 51 is in a deep position in the lamp emission direction, the LED 51 is more difficult to view directly.
The LED 51 is offset to the right from the center of the substrate 52. For example, it is good to arrange at the position of the right third or the position of the right quarter.
Along with the surface of the substrate 52, the substrate mounting surface 69 on the surface of the heat sink 54 is also mirror-finished or has a surface finish with high reflectivity. Alternatively, a diffuse reflection film may be formed on the surface of the substrate attachment surface 69 with the same titanium oxide film as the diffuse reflection portion 80.

*** Variation 2 ***
FIG. 8 is a diagram showing an AA longitudinal section of the LED lamp 50 of the second embodiment.
The difference from FIG. 6 is that the diffuse reflector 80 is on the outer peripheral surface of the glass tube 56. Since the diffuse reflection part 80 is on the outer peripheral surface of the glass tube 56, it is easy to form the diffuse reflection part 80.

*** Variation 3 ***
9, FIG. 10 and FIG. 11 are diagrams showing the LED lamp 50 of the second embodiment.
The difference from FIG. 5 is that the diffuse reflection portion 80 is not uniform in width, and the width of the diffuse reflection portion 80 is a sine curve shape, a concavo-convex shape, a saddle shape, a round mountain shape, a semicircular shape, etc., as in the first embodiment. It is a changing point.
Although not shown, as shown in the first embodiment, the diffuse reflector 80 may be formed only on one side of the substrate 52 up to (before) the light tube intersection line.

Embodiment 3 FIG.
Differences from the first embodiment will be described.
FIG. 12 is a view showing an AA longitudinal section of the LED lamp 50 of the third embodiment.

In FIG. 12, the diffuse reflection unit 80 is on both sides of the light emitting unit 60 or the substrate 52.
The shape of the diffuse reflection portion 80 is a band shape, and has a uniform width in the longitudinal direction.
The effect of the diffuse reflection unit 80 is that when the diffuse reflection unit 80 is irradiated with light from a certain direction, the diffuse reflection unit 80 reflects the light while scattering the light to the surroundings. This is because uniform light emission can be obtained.
In addition, by using the diffuse reflection unit 80, it is possible to irradiate light emitted from the side surfaces until now in a light emitting direction (upward in FIG. 12) with good control.

Hereinafter, the distance between the end portions 81 of the diffuse reflection portion 80 is referred to as an opening width k.
Hereinafter, an angle formed by the light emission center of the LED 51 and both end portions 81 of the diffuse reflection portion 80 (opening angle in the circumferential direction of the opening 85) is referred to as a light emission opening angle γ.
Hereinafter, an angle formed by both end portions 81 of the diffuse reflection portion 80 viewed from the cross-sectional center O of the glass tube 56 (a central angle in the circumferential direction of the opening 85) is referred to as an opening center angle Δ.
Further, as described above, an angle at which the brightness is halved compared to the brightness of the optical axis (center) of the LED 51 is referred to as a light distribution angle h.

  Regarding the positional relationship between the LED 51 and the diffuse reflection part 80 of the straight tube LED lamp using the effect of the diffuse reflection part 80, as a condition in which a diffusion effect is obtained and there is no harmful effect on the brightness, in this embodiment, It is based on the basic way of thinking.

Basic concept 1． The diffusion effect cannot be obtained unless the light emitting aperture angle γ is narrower than the light distribution angle h of the LED 51.
Basic concept 2. If the diffuse reflection area of the diffuse reflector 80 is too large, the opening center angle Δ is narrowed and the illuminance in the lamp emission direction increases, but the light distribution deteriorates, and the effectiveness as illumination is impaired.

  Based on the above basic idea, five examples will be described below.

Example 1.
FIG. 12 shows a straight tube LED lamp in which the diffuse reflection portion 80 is formed so as to protrude from the position X where the light distribution angle h of the LED 51 is extended and intersects the inner surface of the glass.
FIG. 12 shows a configuration based on the basic concept 1 for obtaining the effect of the diffuse reflection section.
The position X is a position at which the light with the light distribution angle h of the LED 51 illuminates the glass tube 56 just beside the LED 51. The position X is in the same plane as the cross section (tube cross section) orthogonal to the longitudinal direction of the LED 51.
Light emitting aperture angle γ <light distribution angle h

Example 2
FIG. 13 shows a straight tube LED lamp in which the LED 51 is arranged at the cross-sectional center O or at the back thereof.
If the light distribution angle h of the LED 51 is about 120 degrees, even if the LED 51 is positioned at the center O where the light distribution is most unfavorable, and the diffuse reflection part 80 is slightly protruded in the light emitting direction from the position X, The light emission opening angle γ (opening center angle Δ) is not too narrow, and a diffuse reflection part having a diffusion effect can be formed.
Luminous aperture angle γ = opening center angle Δ <light distribution angle h = 120 degrees or
LED 51 is arranged at the center O,
Light emitting aperture angle γ = opening center angle Δ = light distribution angle h
It doesn't matter.
As shown by the broken-line arrows in FIG. 13, the LED 51 is not disposed at the center O where light distribution is most disadvantageous, and the positions of the diffuse reflector 80 and the LED 51 are shifted in the radial direction from the cross-sectional center O and disposed at the back. It is desirable.
At that time, without changing the area of the diffuse reflector 80 in accordance with the position of the LED 51 (moving the upper and lower ends of the diffuse reflector 80 as they are), the opening center angle Δ after the change of the position of the LED 51 is set. If it is increased, the same brightness can be obtained while widening the light distribution by the diffusion effect equivalent to that before the change of the position of the LED 51.
On the other hand, the area of the diffuse reflection part 80 is increased in accordance with the position of the LED 51 (the upper end of the diffuse reflection part 80 is left as it is and the lower end of the diffuse reflection part 80 is extended downward), and the opening after the change of the position of the LED 51 is achieved. If the central angle Δ is not changed, the diffusion effect is increased from before the change of the position of the LED 51, so that an effect of improving the brightness with an equivalent light distribution can be obtained.

Example 3
In FIG. 14, a straight tube LED in which the LED 51 is arranged in the back in the radial direction with respect to the cross-sectional center O, and the opening central angle Δ of the opening 85 with respect to the cross-sectional center O is 120 degrees. Indicates a lamp.
In the case of FIG. 14, the opening center angle Δ at the center O is set to 120 degrees regardless of the position of the LED 51.
The reason why the opening center angle Δ is fixed at 120 degrees is that the light distribution angle h of the LED 51 without the normal diffuse reflection section 80 is about 120 degrees. This is because, even if there is the diffuse reflection part 80, if 120 degrees is ensured, it is considered that light distribution substantially equivalent to that of the normal LED 51 can be provided.
Opening center angle Δ = 120 degrees fixed = light distribution angle h
However, in the case where the light distribution angle h of the LED 51 is 120 degrees, the diffusion effect is small or there is no diffusion effect unless the LED 51 is disposed behind the center O.
Thus, in order to improve the diffusion effect, when the opening center angle Δ = light distribution angle h (and when the opening center angle Δ> light distribution angle h), the LED 51 is moved from the cross-sectional center O. Displace in the radial direction and place in the back.
For example, if the opening center angle Δ = 120 ° with respect to the inner diameter of the glass tube of 24 mm, the opening width k = 20.8 mm, which is sufficient as the circumferential width (or opening width k) of the opening 85. .

Example 4
FIG. 15 shows a straight tube LED lamp in which the diffuse reflector 80 is formed to be 20 degrees smaller than the light emission opening angle γ of the LED 51.
FIG. 15 shows a case where the light emission aperture angle γ is 10 degrees narrower to the left and right than the light distribution angle h.
Light emitting aperture angle γ = light distribution angle h−20 degrees ± 10%
For example, if the light distribution angle h is 120 degrees, the inner diameter of the glass tube is 24 mm, the position of the LED 51 is 3 mm behind the center O, and the light emission opening angle γ from the position of the LED 51 is 100 degrees, the opening width k = 20.97 mm. Therefore, the width of the opening 85 in the circumferential direction (or the opening width k) is sufficient.

Example 5 FIG.
FIG. 16 shows a straight tube LED lamp in which the LED 51 is disposed behind the cross-sectional center O, and the diffuse reflection portion 80 is formed to be 84 degrees or more with respect to the cross-sectional center O.
In the case of FIG. 16, the opening center angle Δ at the center O is 84 degrees or more regardless of the position of the LED 51.
Hereinafter, the ratio of the opening width k to the inner diameter of the glass tube is referred to as the opening ratio.
For example, if the opening center angle Δ is 83.6 degrees with respect to the inner diameter of the glass tube of 24 mm, the opening width k is 16 mm. Therefore, the opening 85 is required to have a circumferential width of 84 degrees or more. The aperture ratio is 0.67.

Glass tube inner diameter: 24mm
Opening center angle Δ: 83.6 degrees Opening width k: 16 mm
Aperture ratio: 0.67

When the glass tube has an inner diameter of 24 mm, the opening width k, the opening center angle Δ, and the opening ratio are as follows.
In order to set the opening width k to 17 mm, the opening center angle Δ may be set to 90.2 degrees. The aperture ratio is 0.71.
In order to set the opening width k to 18 mm, the opening center angle Δ may be 97.2 degrees. The aperture ratio is 0.75.
In order to set the opening width k to 19 mm, the opening center angle Δ may be set to 104.6 degrees. The aperture ratio is 0.79.
In order to set the opening width k to 20 mm, the opening center angle Δ may be set to 112.8 degrees. The aperture ratio is 0.83.
In order to set the opening width k to 20.5 mm, the opening center angle Δ may be set to 116.4 degrees. The aperture ratio is 0.85.
In order to set the opening width k to 20.78 mm, the opening center angle Δ may be set to 120.0 degrees. The aperture ratio is 0.87.
In order to set the opening width k to 21 mm, the opening center angle Δ may be set to 122.0 degrees. The aperture ratio is 0.88.
In order to set the opening width k to 22 mm, the opening center angle Δ may be set to 132.8 degrees. The aperture ratio is 0.92.
In order to set the opening width k to 23 mm, the opening center angle Δ may be set to 146.8 degrees. The aperture ratio is 0.96.
In order to set the opening width k to 24 mm, the opening center angle Δ may be set to 180.0 degrees. The aperture ratio is 1.00.
From the basic idea 1 that the diffusion effect cannot be obtained unless the diffuse reflection portion 80 is narrower than the light distribution angle h of the LED 51,
84 degrees ≦ opening center angle Δ <light distribution angle h
It can be said.
If the inner diameter of the glass tube is 24 mm and the light distribution angle h of the LED 51 is 120 degrees,
84 degrees ≦ opening center angle Δ <120 degrees 16 mm ≦ opening width k <20.78 mm
0.67 ≦ aperture ratio <0.87
It becomes.

In the case of a glass tube inner diameter of 24 mm, the following range is desirable.
112.8 degrees ≦ opening center angle Δ <120 degrees 20 mm ≦ opening width k <20.78 mm
0.83 ≦ aperture ratio <0.87

When the glass tube inner diameter is 30.5 mm, the opening width k, the opening center angle Δ, and the opening ratio are as follows.
In order to set the opening width k to 20 mm, the opening center angle Δ may be set to 82.0 degrees. The aperture ratio is 0.66.
In order to set the opening width k to 20.4 mm, the opening center angle Δ may be set to 84.0 degrees. The aperture ratio is 0.67.
In order to set the opening width k to 21 mm, the opening center angle Δ may be set to 87.0 degrees. The aperture ratio is 0.69.
In order to set the opening width k to 22 mm, the opening center angle Δ may be set to 92.4 degrees. The aperture ratio is 0.72.
In order to set the opening width k to 23 mm, the opening center angle Δ may be set to 97.8 degrees. The aperture ratio is 0.75.
In order to set the opening width k to 24 mm, the opening center angle Δ may be set to 103.8 degrees. The aperture ratio is 0.79.
In order to set the opening width k to 25 mm, the opening center angle Δ may be set to 110.2 degrees. The aperture ratio is 0.82.
In order to set the opening width k to 26 mm, the opening center angle Δ may be set to 116.4 degrees. The aperture ratio is 0.85.
In order to set the opening width k to 26.42 mm, the opening center angle Δ may be set to 120.0 degrees. The aperture ratio is 0.87.
In order to set the opening width k to 27 mm, the opening center angle Δ may be set to 124.6 degrees. The aperture ratio is 0.89.
In order to set the opening width k to 28 mm, the opening center angle Δ may be set to 133.2 degrees. The aperture ratio is 0.92.

When the inner diameter of the glass tube is 30.5 mm and the light distribution angle h of the LED 51 is 120 degrees,
84 degrees ≦ opening center angle Δ <120 degrees 20.4 mm ≦ opening width k <26.42 mm
0.67 ≦ aperture ratio <0.87
It becomes.

In the case of a glass tube inner diameter of 30.5 mm, the following range is desirable.
110.2 degrees ≦ opening center angle Δ <120 degrees 25 mm ≦ opening width k <26.42 mm
0.82 ≦ aperture ratio <0.87

*** Variation 1 ***
FIG. 17 shows an example in which there is no heat sink 54. It is desirable to radiate heat using a heat radiating adhesive 90. Since there is no heat sink 54, the light emitting part 60 can be moved and arranged to the inner surface (near) of the glass tube 56 in the radial direction.

*** Variation 2 ***
In FIG. 18, the diffuse reflector 80 is on the outer peripheral surface of the glass tube 56. Since the diffuse reflection part 80 is on the outer peripheral surface of the glass tube 56, it is easy to form the diffuse reflection part 80.
The diffuse reflection portion 80 may be formed separately on the left and right.

*** Variation 3 ***
Moreover, you may use combining each embodiment mentioned above, each Example, and each modification.

Embodiment 4 FIG.
Differences from the above-described first embodiment will be described.

FIG. 19 is a diagram showing the LED lamp 50.
In FIG. 19, compared with FIG. 5 of the second embodiment already described, the distance between the LEDs 51 is even closer.
Although not shown, the LED 51 may be closely spaced in the third embodiment.
Although not shown, in the first embodiment, the distance between the LEDs 51 may be close. In the first embodiment, when the interval between the LEDs 51 is close, the interval between the waves may be reduced according to the interval between the LEDs 51.

FIG. 20 is a view showing a vertical AA section of the LED lamp 50.
In FIG. 20, compared with FIG. 2 of Embodiment 1 already described, the arrangement of the LEDs 51 is not one row but two rows (plural rows). When the arrangement of the LEDs 51 is two (a plurality of), the position of the end 81 of the left diffuse reflector 80 is determined by the light distribution angle h in the left direction of the LEDs 51 in the leftmost column. Further, the position of the end 81 of the right diffuse reflector 80 is determined by the right light distribution angle h of the LEDs 51 in the rightmost column.

FIG. 21 is a diagram showing an AA longitudinal section of the LED lamp 50.
In FIG. 21, compared with FIG. 6 of Embodiment 2 already described, the arrangement of the LEDs 51 is not one row but two rows (plural rows). When the arrangement of the LEDs 51 is two rows (plural rows), the two rows (plural rows) of LEDs 51 may be regarded as if they are one row of LEDs.

  Although not shown, the LEDs 51 may be arranged in an array, grid, honeycomb, zigzag, star, ring, or other pattern instead of a linear pattern. Moreover, LED51 is not arrange | positioned at equal intervals and there may be a part of coarse arrangement and dense arrangement.

<<< Summary of each embodiment >>>
As described above, the LED lamp described in the above embodiment is
A glass tube 56 (cylinder tube);
A substrate 52 on which the LED 51 is mounted, the substrate 52 extending over the longitudinal direction of the glass tube 56 (cylindrical tube);
A diffuse reflection unit 80 that reflects light from the LED 51, the diffuse reflection unit 80 formed on the peripheral surface of the glass tube 56 (cylindrical tube) on the side of the substrate 52;
The diffuse reflection portion 80 has a circumferential width that varies in the longitudinal direction of the glass tube 56 (cylindrical tube).
The circumferential width W2 of the diffuse reflection part 80 between the LEDs 51 is characterized by being larger than the circumferential width W1 of the diffuse reflection part 80 on the side of the LED 51.

  The diffuse reflection portion 80 has a circumferential width that varies across the longitudinal direction of the glass tube 56 (cylindrical tube) so as to reflect the light from the LED 51 outside the light distribution angle of the LED 51. It is characterized by being.

  The diffuse reflection portion 80 is formed up to a position just before the light having a light distribution angle of the LED 51 and the glass tube 56 (cylindrical tube) intersect.

  The diffuse reflection part 80 has a waveform shape.

The diffuse reflector 80 is not present on the side of the LED 51,
The diffuse reflection part 80 has a bowl shape or a mountain shape between the LEDs 51.

The LED lamp described in the above embodiment is
A glass tube 56 (cylinder tube);
A substrate 52 on which the LED 51 is mounted, the substrate 52 extending over the longitudinal direction of the glass tube 56 (cylindrical tube);
A diffuse reflection unit 80 that reflects light from the LED 51, and is formed on the peripheral surface of the glass tube 56 (cylindrical tube) on the side of the substrate 52 in the longitudinal direction of the glass tube 56 (cylindrical tube). Part 80.

  The diffuse reflection portion 80 exists only on one side of the substrate 52 and does not exist on the other side of the substrate 52.

The glass tube 56 (cylinder tube) has an opening 85 that emits light,
The light emission central direction of the LED 51 is inclined with respect to the radial direction of the glass tube 56 (cylindrical tube) passing through the center of the opening 85.

  An angle α formed by the surface of the substrate 52 and the lamp emission center direction is not less than 10 degrees and not more than 80 degrees.

  The diffuse reflection part 80 extends on both sides of the substrate 52 in the longitudinal direction of the glass tube 56 (cylindrical tube), and the glass tube 56 (cylindrical tube) has an opening 85 that emits light. Features.

  The opening 85 is characterized in that it is open on the inner side than the position X at which the light distribution angle h of the LED 51 illuminates the glass tube 56 (cylindrical tube).

  The position X is a position where the light with the light distribution angle h of the LED 51 illuminates the glass tube 56 (cylindrical tube) that is directly beside the LED 51.

  The diffuse reflection part 80 is a diffuse reflection film that diffuses and reflects light from the LED 51.

  The diffuse reflection part 80 has a titanium oxide film formed on the inner surface or the outer surface of a glass tube 56 (cylindrical tube).

  50 LED lamp, 51 LED, 52 substrate, 54 heat sink, 55 base, 56 glass tube, 58 power supply terminal, 60 light emitting portion, 80 diffuse reflection portion, 81 end portion, 85 opening portion, 86 light emission reflection portion, h light distribution angle , Γ emission opening angle, Δ opening center angle.

Claims (16)

In an LED lamp using a light emitting diode (LED),
A tube,
A substrate on which an LED is mounted, the substrate extending in the longitudinal direction of the tube,
A diffuse reflection part for reflecting light from the LED, and a diffuse reflection part formed on the peripheral surface of the tube on the side of the substrate;
The diffuse reflection portion has a circumferential width that changes over the longitudinal direction of the tube,
An LED lamp characterized in that the circumferential width of the diffuse reflection portion between the LEDs is larger than the circumferential width of the diffuse reflection portion on the side of the LED.   The diffuse reflection portion is characterized in that the width in the circumferential direction is changed over the longitudinal direction of the tube so as to reflect the light outside the light distribution angle of the LED out of the light from the LED. The LED lamp according to claim 1.   3. The LED lamp according to claim 1, wherein the diffuse reflection portion is formed to an inner side of a position where light having a light distribution angle of the LED and the tube tube intersect.   The LED lamp according to claim 1, wherein the diffuse reflection portion has a waveform shape. The diffuse reflection part does not exist on the side of the LED,
The LED lamp according to claim 1, wherein the diffuse reflection portion has a bowl shape or a mountain shape between the LEDs. In an LED lamp using a light emitting diode (LED),
A tube,
A substrate on which an LED is mounted, the substrate extending in the longitudinal direction of the tube,
An LED lamp, comprising: a diffuse reflection part for reflecting light from an LED, and a diffuse reflection part formed on a side of a substrate over a longitudinal direction of the tube on the peripheral surface of the tube .   The LED lamp according to claim 1, wherein the diffuse reflection portion exists only on one side of the substrate and does not exist on the other side of the substrate. The cylindrical tube has an opening that emits light,
The LED lamp according to any one of claims 1 to 7, wherein a light emission center direction of the LED is inclined with respect to a radial direction of the tube passing through the center of the opening.   9. The LED according to claim 1, wherein an angle α on the lamp emission direction side formed by a surface of the substrate and a line connecting the LED and an end of the diffuse reflection portion is less than 90 degrees. lamp. The diffuse reflection portion extends on both sides of the substrate over the longitudinal direction of the tube,
7. The LED lamp according to claim 6, wherein the tube has an opening for emitting light. The angle at which the brightness is halved compared to the brightness of the optical axis of the LED is the light distribution angle h,
When the opening angle in the circumferential direction of the opening viewed from the light emission center of the LED is the light emission opening angle γ,
Light emitting aperture angle γ <light distribution angle h
The LED lamp according to claim 10, wherein: The angle at which the brightness is halved compared to the brightness of the optical axis of the LED is the light distribution angle h,
The opening angle in the circumferential direction of the opening viewed from the light emission center of the LED is the light emission opening angle γ,
When the opening angle in the circumferential direction of the opening viewed from the cross-sectional center O of the tube is the opening center angle Δ,
Light emitting aperture angle γ = opening center angle Δ <light distribution angle h
The LED lamp according to claim 10, wherein: The angle at which the brightness is halved compared to the brightness of the optical axis of the LED is the light distribution angle h,
When the opening angle in the circumferential direction of the opening viewed from the cross-sectional center O of the tube tube is the opening center angle Δ,
Opening center angle Δ = light distribution angle h
The LED lamp according to claim 10, wherein: The angle at which the brightness is halved compared to the brightness of the optical axis of the LED is the light distribution angle h,
When the opening angle in the circumferential direction of the opening viewed from the light emission center of the LED is the light emission opening angle γ,
Light emitting aperture angle γ = light distribution angle h−20 degrees ± 10%
The LED lamp according to claim 10, wherein: The opening angle in the circumferential direction of the opening as viewed from the cross-sectional center O of the tube is defined as the opening center angle Δ,
When the ratio of the opening width of the opening and the inner diameter of the glass tube is the opening ratio,
112.8 degrees ≦ opening center angle Δ <120 degrees 0.83 ≦ opening ratio <0.87
Or
110.2 degrees ≦ opening center angle Δ <120 degrees 0.82 ≦ opening ratio <0.87
The LED lamp according to claim 10, wherein:   The LED lamp according to claim 1, wherein the diffuse reflection portion has a titanium oxide film formed on an inner surface or an outer surface of a cylindrical tube.

Images