Solid-state grow lights for plant cultivation

Abstract

This invention discloses a growth lamp, for example, comprising: a broadband blue solid-state light source that generates broadband blue light with a peak emission wavelength between 420 nm and 495 nm; wherein the broadband blue solid-state light source includes a broadband InGaN / GaN multi-quantum-well LED chip, the broadband InGaN / GaN multi-quantum-well LED chip containing multiple quantum wells of different wavelengths in its active region for generating multiple narrowband blue to cyan light emission of multiple different wavelengths; wherein the broadband blue light is composed of a combination of the multiple narrowband blue to cyan light emission; and the broadband blue light has a larger full width at half maximum (FWHM) compared to the narrowband blue to cyan light emission.

Description

Technical Field

[0001] Embodiments of the present invention relate to solid-state grow lights (i.e. light-emitting devices) based on light-emitting diodes (LEDs) for plant cultivation, and more particularly to a solid-state light source for grow lights that promote photosynthesis and plant growth, but are not limited thereto. Background Technology

[0002] Factors such as temperature, humidity, wind, carbon dioxide, root zone temperature, water, nutrients, and oxygen levels play important roles in regulating and promoting plant growth. Furthermore, light intensity, spectral composition, and duration of light exposure play major roles in the plant growth cycle, including plant growth / biomass during photosynthesis, plant morphology (shape) during photomorphogenesis, and flowering time during photoperiod.

[0003] Photosynthesis is the process by which photosynthetic pigments absorb light and convert light energy into chemical energy. Light energy is absorbed by chlorophyll, which is concentrated in chloroplasts within leaf cells. There are two main types of chlorophyll: chlorophyll a (Chl-a) and chlorophyll b (Chl-b). Both chlorophyll a and chlorophyll b have absorption peaks at wavelengths corresponding to the blue and red light regions of the visible spectrum. Light energy plays a crucial role in photosynthesis, influencing plant growth rate and biomass; it can be measured by photon flux density (PFD). In addition to chlorophyll, plants may also contain carotenoids (Caro), such as β-carotene, which have photoprotective properties and play a role in absorbing light during photosynthesis. Carotenoids, such as β-carotene, have absorption peaks corresponding to blue and green light.

[0004] The spectral range (wavelength range) of solar radiation (sunlight) from 400 nm to 700 nm used in photosynthesis is called photosynthetically active radiation (PAR). Previously, it was thought that shorter wavelength photons had high energy and would damage cells and tissues, but most of them were filtered out by the ozone layer in the stratosphere. It was also thought that longer wavelength photons carried insufficient energy for photosynthesis to occur. However, current opinion suggests that far-red light (wavelengths greater than 680 nm) plays a crucial role in photosynthesis through the so-called "Emerson Enhancement Effect," in which photosynthesis is significantly enhanced when plants are simultaneously exposed to both deep red light (approximately 680 nm) and far-red light.

[0005] Spectral composition can regulate plant morphology through photomorphogenesis, which is related to the plant's response to the spectral composition of light (i.e., the distribution of power density with wavelength). In plants, cryptochromes and phototropins regulate plant development based on photomorphogenic effects corresponding to the ultraviolet A (UV-A), ultraviolet B (UV-B), and blue light portions of the electromagnetic spectrum. Cryptochromes are thought to help control seed and seedling development, as well as the transition from the vegetative growth stage to the flowering stage, while phototropins are thought to control directional growth towards blue light sources (phototropism). Phytochrome photoreceptors are located in the red light region (type I phytochrome P...). r ) and in the far-red region (type II phytochrome P) FR Photomorphogenesis has a strong absorption capacity and is believed to be responsible for regulating seed germination (photogermination), chlorophyll synthesis, and flowering time. Controlling the spectral composition of light used in plant reproduction, particularly the ratio of red to blue light, can effectively regulate plant morphology and even the color of certain plant genotypes. Generally, the ultraviolet to blue light band inhibits cell expansion, leading to reduced leaf expansion / stem elongation, while far-red light can enhance leaf expansion / stem elongation. Photomorphogenic responses are highly dependent on plant species. For example, far-red light promotes leaf expansion in leafy green vegetables such as spinach or lettuce, while in most other species (such as tomatoes), it promotes stem growth. In contrast, the photosynthetic processes that control plant growth are largely unaffected by plant species.

[0006] In addition, as mentioned above, controlling the duration of light exposure, or "photoperiod control," can be used to control the flowering time of short-day and long-day plants.

[0007] The lighting requirements for plant growth differ from those for general human vision. The human eye has three types of photoreceptor cells (L-cones, M-cones, and S-cones), which are sensitive to red, green, and blue light, respectively. The eye can detect the proportion of light intensity for each color. Therefore, for general lighting, to ensure accurate color perception (color rendering), it is preferable that white light has an intensity spectrum, i.e., the relationship between intensity and wavelength, which is as close as possible to sunlight in terms of wavelengths from blue to red in the visible spectrum. In contrast, plants convert light energy (photon flux) into chemical energy and are sensitive to photon flux at different wavelengths in the spectrum.

[0008] Unlike the human eye, plants possess different photoreceptors and cells to sense and process light. The unit of measurement for light quantity (intensity) is photosynthetic photon flux (PPF), measured in μmol / s. PPF is a measure of the photosynthetically active radiation (PAR) of a light source. As mentioned above, the ratio of photon flux can affect various plant parameters, such as biomass, morphology, nutrient content, flavor, and flowering time. Therefore, by controlling the ratio of photon flux, horticulturalists can selectively alter / optimize plant characteristics.

[0009] Based on plants' strong absorption of blue and red light, LED-based grow lights produce violet light. These lights consist of a combination of narrowband blue LEDs and red LEDs. The narrowband blue LEDs produce blue light with a dominant wavelength of approximately 450 nm and a full width at half maximum (FWHM) of approximately 20 nm or less, while the red LEDs (or red phosphors) produce red light with a dominant wavelength of approximately 660 nm. Research by McCree et al. (McCree KJ, 1972. The action spectrum, absorptance and quantum yield of photosynthesis in crop plants. Agric. Meteorol., 9:191-216) indicates that the green to yellow portion of the visible spectrum may also play a role in the photosynthetic rate. Therefore, there is increasing interest in white LED-based grow lights. Typically, white grow lights consist of multiple warm white and cool white LEDs and one deep red LED.

[0010] This invention relates to improvements related to solid-state, LED-based grow light emission devices, particularly (but not limited to) improvements to solid-state light sources that produce light in the blue to cyan region of the spectrum for regulating and / or promoting photosynthesis and plant growth. Summary of the Invention

[0011] This invention relates to a light-emitting device (growth lamp) comprising solid-state light-emitting diodes (LEDs) with an emission spectrum in the blue to cyan region of the spectrum (approximately 400 nm to 520 nm), used to promote photosynthesis and plant growth. As described below, relative photosynthetic response curves, the photosynthesis action spectrum (PAS), and the McCree curve show that in the blue to cyan region of 400 nm to 520 nm, where plant absorption efficiency is highest, plant growth efficiency depends not only on photon intensity but also on wavelength.

[0012] According to the present invention, the spectrum generated by the solid-state light source may include one or more blue light emissions, the peak emission wavelength of which corresponds to the peak absorption wavelength of chlorophyll and / or carotenoids, to promote photosynthesis and plant growth. Since chlorophyll a is considered to play the most important role in plant photosynthesis, the spectral composition of the light generated by the solid-state light source may include at least one blue light emission, the peak emission of which substantially matches the peak absorption wavelength of chlorophyll a (approximately 430 nm).

[0013] According to one aspect of the invention, a light-emitting device, such as a growth lamp, is provided, comprising: a broadband blue solid-state light source that generates broadband blue light (emission) having a full width at half maximum (FWHM) of at least 30 nm and a peak emission wavelength of at least one of the following: 420 nm to 440 nm; from 460 nm to 470 nm; and from 450 nm to 465 nm and from 480 nm to 495 nm.

[0014] Studies have shown that although maximum photon absorption occurs at the absorption peak wavelength of pigments, the maximum photosynthetic rate may occur at wavelengths far from the absorption peak wavelength. According to another aspect of the invention, a solid-state light source can generate broadband blue light emission (FWHM from 30 nm to 80 nm), which can increase the photosynthetic rate.

[0015] In this specification, broadband blue light refers to blue light with a full width at half maximum (FWHM) of at least 30 nm, preferably about 40 nm to 80 nm. Broadband can also refer to blue-cyan light composed of a combination of blue-cyan light emission from at least two different wavelengths. Broadband blue-cyan light can be generated using a combination of two or more narrowband blue-cyan light emission from different wavelengths. Narrowband blue-cyan light emission of different wavelengths can be generated in two ways: (i) using multiple individual blue-cyan narrowband LEDs with different peak emission wavelengths, or (ii) using a single broadband LED that generates multiple blue-cyan narrowband emission, for example, using multiple different quantum wells specially designed in their active regions. Therefore, a broadband blue-cyan solid-state light source can consist of one or more narrowband solid-state light sources; such as LEDs or laser diodes, each of which "directly" generates narrowband blue-cyan light with different peak emission wavelengths from 400 nm to 530 nm. Alternatively, a broadband blue-to-cyan solid-state light source also includes a broadband blue solid-state light source; for example, a broadband blue LED, such as an InGaN / GaN blue-to-cyan LED, whose active region utilizes different quantum wells in a multiple-quantum-well (MQW) structure to directly generate multiple blue-to-cyan light emissions of different wavelengths. The broadband solid-state light source of this invention contrasts with photoluminescence-converted (PC) LEDs, which utilize ultraviolet solid-state light sources (UV LEDs) to indirectly generate blue light through a photoluminescence wavelength conversion process using a blue-to-cyan photoluminescent material (phosphor). In other words, the broadband blue-to-cyan solid-state light source according to this invention does not utilize / includes photoluminescent materials to generate blue-to-cyan light.

[0016] In one embodiment, the broadband blue light may substantially match at least one of the absorption peak wavelengths of chlorophyll a, chlorophyll b, and carotenoids.

[0017] In one embodiment, the wideband blue light emission FWHM can be one of the following: at least 40 nm; at least 50 nm; at least 60 nm; and from 40 nm to 80 nm.

[0018] In one embodiment, the broadband blue solid-state light source can generate first broadband blue light at 420 nm to 440 nm with a first blue photon flux, and second broadband blue light at 460 nm to 470 nm with a second blue photon flux, wherein the ratio of the first blue photon flux to the second blue photon flux is 3:1. In this configuration, it should be understood that approximately 75% of the blue photon flux corresponds to the chlorophyll a absorption peak, and approximately 25% of the blue photon flux corresponds to the chlorophyll b absorption peak.

[0019] In one embodiment, the light-emitting device, such as a growth lamp, may further include an orange-to-red LED or an orange-to-red photoluminescent material that produces orange-to-red emission with a peak emission wavelength of 630 nm to 670 nm.

[0020] In one embodiment, the broadband blue light may have a blue photon flux, and the red light may have a red photon flux, wherein the ratio of the blue photon flux to the red photon flux may be at least one of the following: approximately 1:1; approximately 3:1; or approximately 1:3. It should be understood that, in the sense of the 1:1 ratio, "approximately" may correspond to approximately ±0.3. Therefore, it is understood that a ratio of approximately 1:1 includes 0.7:1 to 1.3:1. It should be understood that, in the sense of the 3:1 ratio, "approximately" may correspond to approximately ±0.5. Therefore, it is understood that a ratio of approximately 3:1 includes 2.5:1 to 3.5:1. It should be understood that, in the sense of the 1:3 ratio, "approximately" may correspond to approximately ±1.0. Therefore, it is understood that a ratio of approximately 1:3 includes 1:2 to 1:4.

[0021] In one embodiment, the light-emitting device, such as a growth lamp, may further include a far-red solid-state light source or a far-red photoluminescent material that produces far-red light with a peak emission wavelength of about 680 nm to about 750 nm.

[0022] In one embodiment, the broadband blue solid-state light source may include a plurality of narrowband blue LEDs that generate narrowband blue light emission at multiple different wavelengths.

[0023] In one embodiment, the broadband blue solid-state light source may include a broadband LED with multiple quantum wells of different wavelengths, which can generate narrowband blue light emission of multiple different wavelengths.

[0024] In one embodiment, the broadband blue solid-state light source may include a broadband LED having multiple quantum wells with different wavelengths, the quantum wells generating multiple narrowband blue light emissions with different wavelengths.

[0025] In one embodiment, the light-emitting device, such as a growth lamp, may further include a green to yellow photoluminescent material that produces green to yellow light with a peak emission wavelength of about 540 nm to about 600 nm.

[0026] In one embodiment, the light-emitting device, such as a growth lamp, may further include a cyan to red photoluminescent material that produces cyan to red light with a peak emission wavelength of about 500 nm to about 660 nm.

[0027] According to another aspect of the invention, a growth lamp is conceived comprising: a narrowband blue solid-state light source that generates narrowband blue light having a full width at half maximum (FWHM) of about 10 nm to 30 nm and a peak emission wavelength of at least one of the following: from 425 nm to 435 nm; from 460 nm to 470 nm; from 450 nm to 465 nm and from 480 nm to 495 nm.

[0028] In one embodiment, the narrowband blue light can substantially match at least one of the absorption peak wavelengths of chlorophyll a, chlorophyll b, and carotenoids.

[0029] In one embodiment, the narrowband blue light source can generate a first narrowband blue light at 420 nm to 440 nm with a first blue photon flux and a second narrowband blue light at 460 nm to 470 nm with a second blue photon flux, wherein the ratio of the first blue photon flux to the second blue photon flux is approximately 3:1. In this configuration, it should be understood that approximately 75% of the blue photon flux corresponds to the chlorophyll a absorption peak, and approximately 25% of the blue photon flux corresponds to the chlorophyll b absorption peak.

[0030] In one embodiment, the light-emitting device, such as a growth lamp, may also include a red solid-state light source or a red photoluminescent material that produces red light with a peak emission wavelength of 630 nm to 670 nm.

[0031] In one embodiment, the narrowband blue light may have a blue photon flux, and the red light may have a red photon flux, wherein the ratio of the blue photon flux to the red photon flux may be at least one of the following: about 1:1; about 3:1; or about 1:3. It should be understood that, in the sense of the 1:1 ratio, "about" can correspond to approximately ±0.3. Therefore, it is understood that a ratio of about 1:1 includes 0.7:1 to 1.3:1. It should be understood that, in the sense of the 3:1 ratio, "about" can correspond to approximately ±0.5. Therefore, it is understood that a ratio of about 3:1 includes 2.5:1 to 3.5:1. It should be understood that, in the sense of the 1:3 ratio, "about" can correspond to approximately ±1.0. Therefore, it is understood that a ratio of about 1:3 includes 1:2 to 1:4.

[0032] In one embodiment, the light-emitting device, such as a growth lamp, may further include a far-red solid-state light source or a far-red photoluminescent material that produces far-red light with a peak emission wavelength of about 680 nm to about 750 nm. Light of this wavelength can enhance photosynthesis through the Emerson effect.

[0033] In one embodiment, the light-emitting device, such as a growth lamp, may further include a green to yellow photoluminescent material that produces green to yellow light with a peak emission wavelength of about 540 nm to about 600 nm.

[0034] In one embodiment, the light-emitting device, such as a growth lamp, may further include a cyan to red photoluminescent material that produces cyan to red light with a peak emission wavelength of about 500 nm to about 660 nm.

[0035] According to another aspect of the invention, a growth lamp is conceived comprising: a broadband full-spectrum blue solid-state light source that produces full-spectrum blue light from 400 nm to 520 nm, wherein the emission intensity of the spectrum varies by less than 25% over a wavelength range of at least 40 nm.

[0036] In one embodiment, the emission intensity may vary by less than 20%, less than 15%, or less than 10% within a wavelength range of at least 40 nm.

[0037] In one embodiment, the variation in emission intensity from 430 nm to 470 nm or from 440 nm to 465 nm may be less than 10%.

[0038] In one embodiment, the broadband full-spectrum blue solid-state light source may include a plurality of broadband blue LEDs, each LED producing broadband blue emission with a peak emission wavelength of 400 nm to 520 nm.

[0039] In one embodiment, the light-emitting device, such as a growth lamp, further includes a red solid-state light source or a red photoluminescent material that produces red light with a peak emission wavelength of 630 nm to 700 nm.

[0040] In one embodiment, the broadband full-spectrum blue light may have a blue photon flux, and the red light may have a red photon flux, wherein the ratio of the blue photon flux to the red photon flux may be at least one of the following: about 1:1; about 3:1; or about 1:3. It should be understood that, in the sense of the 1:1 ratio, "about" can correspond to approximately ±0.3. Therefore, it is understood that a ratio of about 1:1 includes 0.7:1 to 1.3:1. It should be understood that, in the sense of the 3:1 ratio, "about" can correspond to approximately ±0.5. Therefore, it is understood that a ratio of about 3:1 includes 2.5:1 to 3.5:1. It should be understood that, in the sense of the 1:3 ratio, "about" can correspond to approximately ±1.0. Therefore, it is understood that a ratio of about 1:3 includes 1:2 to 1:4.

[0041] In one embodiment, the light-emitting device, such as a growth lamp, may further include a far-red solid-state light source or a far-red photoluminescent material that produces far-red light with a peak emission wavelength of about 680 nm to about 750 nm.

[0042] In one embodiment, the light-emitting device, such as a growth lamp, may further include a green to yellow photoluminescent material that produces green to yellow light with a peak emission wavelength of about 540 nm to about 600 nm.

[0043] In one embodiment, the light-emitting device, such as a growth lamp, further includes a cyan to red photoluminescent material that produces cyan to red light with a peak emission wavelength of about 500 nm to about 660 nm.

[0044] According to another aspect of the invention, the invention includes a growth lamp comprising: a blue solid-state light source that generates blue light with a blue photon flux and a red solid-state light source that generates red light with a red photon flux, wherein the ratio of the blue photon flux to the red photon flux may be at least one of the following: about 1:1; about 3:1; or about 1:3. It should be understood that, in the sense of the 1:1 ratio, "about" may correspond to approximately ±0.3. Therefore, it is understood that a ratio of about 1:1 includes 0.7:1 to 1.3:1. It should be understood that, in the sense of the 3:1 ratio, "about" may correspond to approximately ±0.5. Therefore, it is understood that a ratio of about 3:1 includes 2.5:1 to 3.5:1. It should be understood that, in the sense of the 1:3 ratio, "about" may correspond to approximately ±1.0. Therefore, it is understood that a ratio of about 1:3 includes 1:2 to 1:4.

[0045] In one embodiment, the blue solid-state light source may include a broadband blue solid-state light source, wherein the broadband blue light produced has a full width at half maximum (FWHM) of at least 30 nm and a peak emission wavelength of at least one of the following: from 420 nm to 440 nm; from 460 nm to 470 nm; and from 450 nm to 465 nm and from 480 nm to 495 nm.

[0046] In one embodiment, the broadband blue light can substantially match at least one of the absorption peak wavelengths of chlorophyll a, chlorophyll b, and carotenoids.

[0047] In one embodiment, the blue solid-state light source can generate a first broadband blue light from 420 nm to 440 nm with a first blue photon flux and a second broadband blue light from 460 nm to 470 nm with a second blue photon flux, wherein the ratio of the first blue photon flux to the second blue photon flux is approximately 3:1. In this configuration, it should be understood that approximately 75% of the blue photon flux corresponds to the chlorophyll a absorption peak and approximately 25% of the blue photon flux corresponds to the chlorophyll b absorption peak.

[0048] In one embodiment, the full width at half maximum (FWHM) of the broadband blue light can be one of the following: at least 40 nm; at least 50 nm; at least 60 nm; and from 40 nm to 80 nm.

[0049] In one embodiment, the broadband blue solid-state light source may include a plurality of narrowband blue LEDs that generate narrowband blue light emission at multiple different wavelengths.

[0050] In one embodiment, the broadband blue solid-state light source may include a broadband LED with multiple quantum wells of different wavelengths, which can generate narrowband blue light emission of multiple different wavelengths.

[0051] In one embodiment, the blue solid-state light source can generate full-spectrum blue light from 400 nm to 520 nm, with the emission intensity of the spectrum varying by less than 25% over a wavelength range of at least 40 nm.

[0052] In one embodiment, the emission intensity may vary by less than 20%, less than 15%, or less than 10% within a wavelength range of at least 40 nm.

[0053] In one embodiment, the variation in emission intensity from 430 nm to 470 nm or from 440 nm to 465 nm may be less than 10%.

[0054] In one embodiment, the red solid-state light source may include a red LED and a red photoluminescent material.

[0055] In one embodiment, the light-emitting device, such as a growth lamp, may further include a far-red solid-state light source or a far-red photoluminescent material that produces far-red light with a peak emission wavelength of about 680 nm to about 750 nm.

[0056] In one embodiment, the light-emitting device, such as a growth lamp, may further include a green to yellow photoluminescent material that produces green to yellow light with a peak emission wavelength of about 540 nm to about 600 nm.

[0057] In one embodiment, the light-emitting device, such as a growth lamp, may further include a cyan to red photoluminescent material that produces cyan to red light with a peak emission wavelength of about 500 nm to about 660 nm.

[0058] According to another aspect of the invention, a solid-state light source can generate full-spectrum blue light, the spectral composition of which has an emission maximum at wavelengths in the blue to cyan region of the spectrum, more specifically, at wavelengths of 400 nm to 520 nm in the photosynthetically active radiation (PAR) region, and its intensity is substantially constant (variing less than about 25%) in the blue to cyan region of the spectrum. At wavelengths in the blue to cyan region of the spectrum, the full-spectrum blue light has a spectral composition that more closely matches (similar to) sunlight / daylight. The full-spectrum blue light can have a spectral composition that substantially matches (similar to) the PAS or McCree relative photosynthetic response curves. The full-spectrum blue solid-state light source can include two or more broadband solid-state light sources.

[0059] The solid-state light sources of various aspects of this invention can be used in conjunction with red-emitting LEDs or red phosphors that produce red light emission, the peak emission wavelength of which corresponds to the absorption peak of chlorophyll in the red region of the absorption spectrum. The light-emitting device may also include red LEDs or red photoluminescent materials for producing far-red light emission from 680 nm to 750 nm. When used in conjunction with red light in photosynthetically active radiation (400 nm to 700 nm), photosynthesis can be increased through the Emerson enhancement effect. The solid-state light source can also be used in conjunction with broadband yellow to green emitting phosphors to produce a broadband white light spectrum in horticultural applications.

[0060] According to one aspect of the invention, a light-emitting device is conceived, comprising: a broadband blue solid-state light source, wherein the broadband light emitted has a full width at half maximum (FWHM) of at least 30 nm and a peak emission wavelength of at least one of the following: 420 nm to 440 nm; from 460 nm to 470 nm; and from 450 nm to 465 nm and from 480 nm to 495 nm.

[0061] In one embodiment, broadband light emission with a peak emission wavelength of 425 nm to 435 nm can substantially match the absorption peak wavelength of chlorophyll a. Broadband light emission with a peak emission wavelength of 460 nm to 470 nm can substantially match the absorption peak wavelength of chlorophyll b. Broadband light emission with peak emission wavelengths of 450 nm to 465 nm and 480 nm to 495 nm can substantially match the absorption peak wavelengths of carotenoids.

[0062] In one embodiment, the light-emitting device further includes an LED or a photoluminescent material for generating light emission with a peak emission wavelength of 630 nm to 670 nm.

[0063] In one embodiment, the full width at half maximum (FWHM) of the blue light emission can be one of the following: at least 30 nm, at least 40 nm, at least 50 nm, at least 60 nm, and from 40 nm to 80 nm. In embodiments of the invention, the broadband blue solid-state light source includes a plurality of narrowband blue LEDs for generating narrowband blue light emission at multiple different wavelengths. In some embodiments, the broadband blue solid-state light source includes a broadband LED having a plurality of quantum wells (QWs) of different wavelengths for generating narrowband blue light emission at multiple different wavelengths.

[0064] In one embodiment, when the light-emitting device is used to generate white light, the light-emitting device further includes a green to yellow photoluminescent material that generates light with a peak emission wavelength of about 540 nm to about 600 nm, or a cyan to red photoluminescent material that generates light with a peak emission wavelength of about 500 nm to about 660 nm.

[0065] In one embodiment, the light-emitting device may further include a red LED or a red photoluminescent material for generating light with a peak emission wavelength of about 680 nm to about 750 nm. Light of this wavelength can enhance photosynthesis through the Emerson enhancement effect.

[0066] According to another aspect of the present invention, a light-emitting device is provided, comprising: a narrowband blue solid-state light source for generating narrowband light emission, having a full width at half maximum (FWHM) of about 10 nm to 30 nm and a peak emission wavelength of at least one of the following: 425 nm to 435 nm; 460 nm to 470 nm; 450 nm to 465 nm and 480 nm to 495 nm.

[0067] In one embodiment, narrowband light emission with a peak emission wavelength of 425 nm to 435 nm can substantially match the absorption peak wavelength of chlorophyll a. Narrowband light emission with a peak emission wavelength of 460 nm to 470 nm can substantially match the absorption peak wavelength of chlorophyll b. Narrowband light emission with peak emission wavelengths of 450 nm to 465 nm and 480 nm to 495 nm can substantially match the absorption peak wavelengths of carotenoids.

[0068] In one embodiment, the light-emitting device further includes an LED or a photoluminescent material for generating red light emission with a peak emission wavelength of 630 nm to 700 nm.

[0069] In one embodiment, when the light-emitting device is used to generate white light, the light-emitting device further includes a green to yellow photoluminescent material that generates light with a peak emission wavelength of about 540 nm to about 600 nm, or a cyan to red photoluminescent material that generates light with a peak emission wavelength of about 500 nm to about 660 nm.

[0070] In one embodiment, the light-emitting device further includes a red LED or a red photoluminescent material for generating light with a peak emission wavelength of about 680 nm to about 750 nm. Light of this wavelength can enhance photosynthesis through the Emerson enhancement effect.

[0071] According to another aspect of the invention, the light-emitting device comprises: a broadband full-spectrum blue solid-state light source for generating full-spectrum blue light in the range of 400 nm to 520 nm, wherein the emission intensity of its spectrum varies by less than 25% over a wavelength range of at least 40 nm. This spectral composition substantially matches the PAS and McCree curves and is considered to promote plant growth. Within the wavelength range of at least 40 nm, the emission intensity may vary by less than 20%, less than 15%, or less than 10%. In embodiments of the invention, the variation in emission intensity between 430 nm and 470 nm or between 440 nm and 465 nm is preferably less than 10%.

[0072] In one embodiment, a broadband full-spectrum blue solid-state light source may include a plurality of broadband blue LEDs, each LED being used to generate broadband blue emission with a peak emission wavelength of 400 nm to 520 nm.

[0073] In one embodiment, when the light-emitting device is used to generate white light, the light-emitting device further includes a green to yellow photoluminescent material that generates light with a peak emission wavelength of about 540 nm to about 600 nm, or a cyan to red photoluminescent material that generates light with a peak emission wavelength of about 500 nm to about 660 nm.

[0074] In one embodiment, the light-emitting device may further include a red LED or a red photoluminescent material for generating light with a peak emission wavelength of about 680 nm to about 750 nm. Light of this wavelength can enhance photosynthesis through the Emerson enhancement effect.

[0075] As discussed in this article, while wavelengths in the blue to cyan region of the spectrum are important for plant photosynthesis and reproduction, the relative number of photons (photon flux) in the blue and red regions of the spectrum is another important factor.

[0076] In some configurations of this invention, the number of blue photons may be substantially equal to the number of red photons. The inventors have determined that a growth lamp having a spectrum comprising substantially equal numbers of blue and red photons can promote photosynthesis.

[0077] In other configurations of the invention, the number of blue photons may be greater than the number of red photons. The inventors have determined that grow lights with a spectrum including a greater number of blue photons than red photons can promote plant reproduction.

[0078] In a further embodiment of the invention, the number of red photons may be greater than the number of blue photons. The inventors have determined that a grow light having a spectrum including a greater number of red photons than blue photons can promote flowering.

[0079] According to one aspect of the invention, a solid-state light source can generate narrowband blue light emission (FWHM less than 25 nm). It is assured that narrowband emission can maximize photosynthetic energy absorption and photosynthetic efficiency. The narrowband solid-state light source may include a narrowband LED. Attached Figure Description

[0080] These and other aspects and features of the invention will become apparent to those skilled in the art from the following description of specific embodiments of the invention in conjunction with the accompanying drawings, wherein:

[0081] Figure 1A Absorption spectra of photosynthetic pigments: (i) chlorophyll a (solid line - Chl-a), (ii) chlorophyll b (dotted line - Chl-b), and (iii) carotenoids (dashed line - Caro), showing the absorption rate (%) as a function of wavelength (nm).

[0082] Figure 1B The relative photosynthetic response (%) as a function of wavelength (nm) is the photosynthesis action spectrum (PAS).

[0083] Figure 1C The McCree curve shows the relative photosynthetic response as a function of wavelength (nm).

[0084] Figure 2A and 2B This is a schematic diagram of an encapsulated light-emitting device provided by the present invention, wherein... Figure 2A This is a plan view of the device. Figure 2B This is a cross-sectional side view of the device in the AA direction;

[0085] Figure 3The normalized absorption spectrum of chlorophyll a (dotted line - Chl-a) as a function of wavelength (nm) is shown, along with the absorption spectra of light absorbed by chlorophyll a for (i) a narrowband blue solid-state light source Dev.1 (solid line - Dev.1) and (ii) light absorbed by chlorophyll a (dashed line - Dev.1). Chl-a The spectral power distribution of its spectral power (W / nm) as a function of wavelength (nm);

[0086] Figure 4 Normalized absorption spectra of chlorophyll b (dotted line - Chl-b) as a function of wavelength (nm), and (i) light absorbed by a narrow-band blue solid-state light source Dev.2 (solid line - Dev.2) and (ii) light absorbed by chlorophyll b (dashed line - Dev.2). chl-b The spectral power distribution of its spectral power (W / nm) as a function of wavelength (nm);

[0087] Figure 5 Normalized absorption spectra of chlorophyll a (dotted line - Chl-a) as a function of wavelength (nm), and (i) light absorbed by a broadband blue solid-state light source Dev.3 (solid line - Dev.3) and (ii) light absorbed by chlorophyll a (dashed line - Dev.3). Chl-a The spectral power distribution of its spectral power (W / nm) as a function of wavelength (nm);

[0088] Figure 6 Normalized absorption spectra of chlorophyll b (dotted line - Chl-b) as a function of wavelength (nm), and (i) light absorbed by a broadband blue solid-state light source Dev.4 (solid line - Dev.4) and (ii) light absorbed by chlorophyll b (dashed line - Dev.4). Chl-b The spectral power distribution of its spectral power (W / nm) as a function of wavelength (nm);

[0089] Figure 7 Normalized absorption spectra of carotenoids (dotted line - Caro) as a function of wavelength (nm), and (i) light absorbed by a broadband blue solid-state light source Dev.5 (solid line - Dev.5) and (ii) light absorbed by carotenoids (dashed line - Dev.5). Caro The spectral power distribution of its spectral power (W / nm) as a function of wavelength (nm);

[0090] Figure 8 The spectral power distribution of Dev.6 (solid line - Dev.6), a white light emitting device (growth lamp) using a broadband blue solid-state light source, varies with wavelength (nm), and the absorption spectrum of chlorophyll a (dotted line - Chl-a) varies with wavelength (nm).

[0091] Figure 9For Dev.6 (solid line - Dev.6), the spectral power distribution as a function of wavelength (nm) and the McCree curve (dashed line - McCree) are shown.

[0092] Figure 10 Normalized absorption spectra of chlorophyll a (dotted line - Chl-a) and chlorophyll b (dashed line - Chl-b) as a function of wavelength (nm), and spectral power distribution of broadband full-spectrum blue solid-state light source Dev.7 (solid line - Dev.7) as a function of wavelength (nm).

[0093] Figure 11 The normalized absorption spectrum of chlorophyll a (dotted line - Chl-a) as a function of wavelength (nm), and the light absorbed by chlorophyll a (solid line - Dev.7). Chl-a The spectral power distribution of its spectral power (W / nm) as a function of wavelength (nm);

[0094] Figure 12 The normalized absorption spectrum of chlorophyll b (dotted line - Chl-b) as a function of wavelength (nm), and the light absorbed by chlorophyll b (solid line - Dev.7). Chl-b The spectral power distribution of its spectral power (W / nm) as a function of wavelength (nm);

[0095] Figure 13 Absorption spectra of photosynthetic pigments: (i) chlorophyll a (dotted line - Chl-a) and (ii) chlorophyll b (dashed line - Chl-b) with their absorptivity (%) as a function of wavelength (nm), and spectral power distribution of a purple light-emitting device (growth lamp) Dev.8 (solid line - Dev.8) using a broadband full-spectrum blue solid-state light source with its spectral power as a function of wavelength (nm);

[0096] Figure 14 The spectral power distribution and PAS (thick solid line) of the Dev.8 (thin solid line - Dev.8) using a broadband full-spectrum blue solid-state light source as a function of wavelength (nm);

[0097] Figure 15 The emission spectrum of Dev.9 (solid line - Dev.9), a white light emission device (grow lamp) using a full-spectrum white light solid-state light source, is shown as a function of wavelength (nm). The Planck trajectory (dashed line - 4000K BBL) of the CCT (blackbody trajectory - BBL) at 4000K is shown as a function of wavelength (nm). The McCree curve (dotted line - McCree) is also shown.

[0098] Figure 16The spectral power distribution of the purple growth lamp as a function of wavelength (nm) utilizes: (i) a narrow-band blue solid-state light source (dotted line - narrow-band blue), (ii) a broadband blue solid-state light source (dashed line - broadband blue), and (iii) a broadband full-spectrum blue solid-state light source (thin solid line - full-spectrum blue) and PAS (thick solid line - PAS).

[0099] Figure 17A and Figure 17B A planar schematic diagram of a growth lamp including a broadband blue solid-state light source provided for the present invention;

[0100] Figure 18 The radiation power spectrum of Dev.10 (solid line - Dev.10), a broadband blue solid-state light source, as a function of wavelength (nm), and the absorption spectrum of chlorophyll a (dotted line - Chl-a), as a function of wavelength (nm).

[0101] Figure 19 The radiation power spectrum of Dev.11 (solid line - Dev.11), a broadband blue solid-state light source, as a function of wavelength (nm), and the absorption spectrum of chlorophyll b (dotted line - Chl-b), as a function of wavelength (nm).

[0102] Figure 20 The relative radiative power spectrum of the broadband red solid-state light source Dev.12 (solid line - Dev.12) as a function of wavelength (nm);

[0103] Figure 21 The emission spectrum of the grow lamp Dev.13 (solid line - Dev.13) as a function of wavelength (nm), and the absorption spectrum of chlorophyll a (dotted line - Chl-a) as a function of wavelength (nm).

[0104] Figure 22 The emission spectrum of the grow lamp Dev.14 (solid line - Dev.14) as a function of normalized intensity and wavelength (nm); and

[0105] Figure 23 The emission spectrum of the Dev.15 growth lamp (solid line - Dev.15) is a normalized intensity as a function of wavelength (nm). Detailed Implementation

[0106] Embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which serve as illustrative examples to enable those skilled in the art to practice the invention. It is important to note that the following drawings and examples are not intended to limit the scope of the invention to a single embodiment, but rather to enable other embodiments by interchange of some or all of the elements described or illustrated. Furthermore, where certain elements of the invention can be implemented using some or all of known components, only those portions of these known components necessary for understanding the invention will be described, and detailed descriptions of other portions of these known components will be omitted so as not to obscure the invention. Embodiments showing a single component in this specification should not be considered limiting; rather, the invention is intended to cover other embodiments comprising multiple identical components, and vice versa, unless expressly stated otherwise herein. Furthermore, the applicant does not intend to attribute any terminology in the specification or claims to uncommon or special meanings unless expressly stated otherwise. Moreover, the invention includes present and future known equivalents of the known components mentioned herein by way of illustration.

[0107] As described herein, embodiments of the present invention relate to grow lights (light-emitting devices) including solid-state light sources (LEDs) that produce blue light with peak emission wavelengths corresponding to the peak absorption wavelengths of chlorophyll and / or carotenoids to promote photosynthesis and plant growth. The solid-state light source can be narrowband, broadband, or full-spectrum. In this specification, narrowband blue light refers to light with a full width at half maximum (FWHM) of less than 25 nm, broadband blue light refers to light with a FWHM from 30 nm to 80 nm, and full-spectrum blue light refers to light with substantially constant intensity (i.e., intensity variation less than 25%) within a wavelength range of 40 nm.

[0108] The violet-emitting grow lamp may include the solid-state light source of this invention, used in conjunction with a red-emitting LED or red phosphor that emits red light, the peak emission wavelength of which corresponds to the absorption peak of chlorophyll in the red region of the spectrum. The light-emitting device also includes a red LED or red photoluminescent material that produces far-red light emission. When used in conjunction with red light (400 nm to 700 nm) in photosynthetically active radiation (PAR), photosynthesis can be increased through the Emerson Enhancement Effect.

[0109] White light grow lights can include broadband yellow to green photoluminescent materials (phosphors) that produce white light. This light is beneficial for promoting plant growth and aids in the visual inspection of plant growth.

[0110] In the specification of this invention, Dev.# is used to denote the growth lamp (light-emitting device) and solid-state light source according to embodiments of the invention.

[0111] Figure 1A Absorption spectra of photosynthetic pigments: (i) chlorophyll a (solid line - Chl-a), (ii) chlorophyll b (dotted line - Chl-b), and (iii) carotenoids (dashed line - Caro), showing the absorption rate (%) as a function of wavelength (nm).

[0112] like Figure 1A As shown, chlorophyll a has: (i) an absorption peak 10a with a peak absorption wavelength of about 430 nm in the blue light region of the spectrum, having a peak absorption of about 66% (0.66) and (ii) a second absorption peak 10b with a peak absorption wavelength of about 665 nm in the red light region of the spectrum, having a peak absorption of about 58% (0.58). Chlorophyll b has: (i) an absorption peak 20a with a peak absorption wavelength of about 465 nm in the blue light region of the spectrum, having a peak absorption of about 85% (0.85) and (ii) a second absorption peak 20b with a peak absorption wavelength of about 650 nm in the red light region of the spectrum, having a peak absorption of about 35% (0.35). Carotenoids have: (i) an absorption peak 30a with a peak absorption wavelength of about 62% (0.62) at a peak absorption wavelength of about 457 nm in the blue light region of the spectrum and (ii) a second absorption peak 30b at a peak absorption wavelength of about 486 nm in the blue light region of the spectrum.

[0113] Figure 1B The relative photosynthetic response (%) as a function of wavelength (nm) is shown in the photosynthesis action spectrum (PAS). This spectrum is the average spectrum of plants including chlorophyll a, chlorophyll b, and carotenoids (β-carotene). It is well known that different plant species absorb different light and therefore have different photosynthetic action spectra. Figure 1B The photosynthetic spectrum shown is the average of the photosynthetic spectrum curves of many different plant varieties.

[0114] like Figure 1BAs shown, the photosynthetic activity spectrum has a peak 40 with a maximum value (100%) at approximately 440 nm in the blue light region of the spectrum, and a second, lower peak 50 at approximately 675 nm in the red light region of the spectrum. For the wavelengths between peaks 40 and 50 in the green to yellow region of the spectrum (540 nm to 570 nm), there is a deep trough in the photosynthetic activity spectrum, which reaches a minimum near 550 nm. This trough in the PAS indicates that light in the green to yellow region of the spectrum contributes little to plant photosynthesis.

[0115] Figure 1C The McCree curves show the average photosynthetic response to absorbed photons at different wavelengths, and are plots of the relative photosynthetic response as a function of wavelength (nm). Like PAS, the McCree curves are composite (average) absorption curves for various plants, including chlorophyll a, chlorophyll b, and carotenoids (β-carotene). From... Figure 1C It can be seen that the quantum yield has a maximum value (100%) for wavelengths from approximately 600 nm to approximately 630 nm, which indicates that, compared with PAS ( Figure 1B In comparison, red light plays a greater role in the rate of photosynthesis than blue light. Furthermore, the McCree curves indicate that green to yellow light may also play a role in photosynthesis. For wavelengths from 380 nm to 730 nm, the McCree curves closely resemble the spectrum of sunlight.

[0116] Both PAS and McCree curves indicate that plant growth efficiency depends not only on photon intensity but also on wavelengths in the blue-cyan region from 400 nm to 520 nm, where plants exhibit maximum absorption efficiency. Embodiments of this invention relate to a solid-state light source that generates light in the blue-cyan region, the spectral composition of which is designed to promote plant growth efficiency.

[0117] Photon flux (PF), photosynthetic photon flux (PF) PPF, photosynthesis factor, and photosynthetic photon efficiency. Efficacy, PPE)

[0118] As is well known, photon flux (PF) is a measure of the total number of photons emitted by a light source per second. Typically, photon flux is calculated using all the wavelengths of light.

[0119] Photosynthetic photon flux (PPF) is a measure of the total amount of photosynthetically active radiation produced by a light source; that is, the photon flux (total number of photons emitted per second) of the light source in the wavelength range of photosynthetically active radiation (PAR) from 400 nm to 700 nm. The calculation assumes that no photosynthesis occurs at shorter or longer wavelengths. Photosynthetic photon flux (PPF) of a light source. source The calculation formula is:

[0120]

[0121] Where P(λ) is the spectral power distribution (SPD) of the light source.

[0122] The formula for calculating photon flux (number of photons per second) is:

[0123] Photon Flux = PPF source ×N A ×1000(s -1 );

[0124] Where, N A It is Avogadro's constant (6.02214076 × 10⁻⁶). 23 ).

[0125] The photosynthetic photon flux of light absorbed by pigments (pig.), PPF pig. The calculation formula is as follows:

[0126]

[0127] Wherein, B(λ) is the absorption spectrum of the pigment.

[0128] The photosynthetic factor is a measure of the amount of photosynthetic photon flux absorbed by pigments, and its calculation formula is:

[0129] Photosynthesis Factor = PPF pig. / PPF source (%).

[0130] Photosynthetic photon efficiency (PPE or Kp) is a measure of the energy efficiency of plant lighting. PPE is the photosynthetic photon flux (PPF) of the light source divided by the input electrical power of the light source, and is given by the following formula:

[0131] PPF source =PPF source / electrical power (μmol / J).

[0132] Growth light source (light-emitting device)

[0133] As described herein, embodiments of the present invention may include a grow light source (light-emitting device) for horticultural lighting, comprising one or more blue solid-state light sources (LEDs) that produce a peak emission wavelength λ. pe Light ranges from 400 nm to 520 nm (blue to cyan). The peak emission wavelength can be selected to correspond to the peak absorption wavelength of chlorophyll and / or carotenoids to promote photosynthesis and plant growth.

[0134] One or more solid-state light sources may include one or more InGaN / GaN LED chips that can produce narrowband blue light, broadband blue light, or full-spectrum blue light. In some embodiments, one or more LED chips may be packaged in a surface mount device (SMD) package.

[0135] Figure 2A and 2B This is a schematic diagram of the SMD packaged light-emitting device 100 of the present invention, wherein... Figure 2A This is a plan view of the device. Figure 2B This is a side view of section AA.

[0136] The light-emitting device 100 is a packaged device, including a package 110, such as an SMD (Surface Mount Device) 2835 LED package. The package 110 includes a base 112 and sidewalls 114 extending upward from opposite edges of the base 112. The inner surfaces of the sidewalls 114 are inclined inward relative to their vertical axes in the direction toward the base 112, and together with the inner surface (bottom surface) of the base 112, form a cavity 116.

[0137] Cavity 116 contains one or more (two as shown) InGaN-based LED chips (blue LED chips) 118, mounted on the base plate (inner surface of the base) of cavity 116. As indicated, the LED chips 118 can be electrically connected to contact pads on the bottom of the cavity via bonding wires 120. The contact pads are electrically connected to contact pads on the base of packages 122a, 122b.

[0138] Cavity 116 is filled with a light-transmitting (transparent) material (optical sealant) 124, such as silicone resin. The light-transmitting material 124 may contain light-scattering particles or light-diffusing materials.

[0139] Growth lamps including narrow-band blue solid-state light sources

[0140] As described herein, embodiments of the present invention may include grow lights (light-emitting devices) for horticultural lighting, comprising one or more narrowband blue solid-state light sources that produce a peak emission wavelength λ. pe It is a narrow band of light from 400nm to 520nm (blue to cyan) with an FWHM of 10nm to 25nm. The peak emission wavelength can be selected to correspond to the peak absorption wavelength of chlorophyll and / or carotenoids to promote photosynthesis and plant growth.

[0141] Solid-state light source Dev.1 is a narrowband blue solid-state light source used in this invention to promote photosynthesis involving chlorophyll a. Dev.1 includes a narrowband InGaN / GaN LED that produces a peak emission wavelength (λ) corresponding to the peak absorption wavelength (approximately 430 nm) of chlorophyll a in the blue region of the spectrum. pe Narrowband emission (436nm)

[0142] Table 1 shows the optical characteristics of the narrowband blue solid-state light source Dev.1. As can be seen from the table, Dev.1 has a peak emission wavelength λ of approximately 430 nm. pe And approximately 12nm FWHM.

[0143] Figure 3 The diagram shows the spectral power distribution (SPD) of the narrowband blue solid-state light source Dev.1 (solid line - Dev.1) as a function of wavelength (nm), and the light absorbed by chlorophyll a (dashed line - Dev.1). Chl-a SPD of chlorophyll a (Dev.1) Chl-a The SPD of absorbed light was obtained by scaling the spectral power value of the Dev.1 SPD using the normalized absorption spectrum of Chl-a. The normalized absorption spectrum of Chl-a is the absorption spectrum of Chl-a that has been normalized to have a maximum absorbance value equal to 1. Therefore, the spectral power value of chlorophyll a absorption should be multiplied by 0.66 to obtain the absolute value. For visual comparison, Figure 3 It also includes the normalized absorption spectrum of chlorophyll a (dotted-line - Chl-a) as a function of wavelength.

[0144] The photosynthetic photon flux (PPF) generated by Dev.1 Dev.1 The concentration of PPF absorbed by Chl-a is 0.4166 μmol / s. Chl-a The photosynthetic factor (PPF) is 0.2342 μmol / s. Chl-a / PPF Dev.1 The figure is 56%. In Table 1, the values ​​in parentheses are calculated using normalized absorption spectroscopy. Photosynthetic photon efficiency (PPE) of Dev.1 Dev.1 It is 2.4353 μmol / J.

[0145]

[0146] The narrowband blue solid-state light source Dev.2 is a narrowband solid-state light source used in this invention to promote photosynthesis involving chlorophyll b. Dev.2 includes a narrowband InGaN LED that produces a peak emission wavelength (λ) corresponding to the peak absorption wavelength (approximately 465 nm) of chlorophyll b in the blue region of the spectrum. peNarrowband emission (461nm)

[0147] Table 2 presents the optical characteristics of the narrowband blue solid-state light source Dev.2. As can be seen from the table, Dev.2 has a peak emission wavelength λ of approximately 468 nm. pe And approximately 18nm FWHM.

[0148] Figure 4 The diagram shows the spectral power distribution (SPD) of Dev.2 (solid line - Dev.2) as a function of wavelength (nm), and the SPD of light absorbed by chlorophyll b (dashed line - Dev.2). Chl-b ). Chlorophyll b (Dev.2) Chl-b The SPD of absorbed light was obtained by scaling the spectral power value of the Dev.2 SPD using the normalized absorption spectrum of Chl-b. The normalized absorption spectrum of Chl-b is obtained by normalizing Chl-b to have an absorption spectrum with a maximum absorbance value equal to 1. Therefore, the spectral power value of chlorophyll b absorption was scaled by 0.85 to obtain the absolute value. For comparison, Figure 4 It also includes the normalized absorption spectrum of chlorophyll b (dotted-line - Chl-b) as a function of wavelength.

[0149] The photosynthetic photon flux (PPF) generated by Dev.2 Dev.2 The concentration was 0.4147 μmol / s. The PPF absorbed by Chl-b was [missing value]. Chl-b The photosynthetic factor (PPF) was 0.28543 μmol / s. Chl-b / PPF Dev.2 The photosynthetic photon efficiency (PPE) of Dev.2 is 69%. In Table 2, the values ​​in parentheses are calculated using normalized absorption spectroscopy.

[0150]

[0151] Growth lamps including broadband blue solid-state light sources

[0152] As described herein, embodiments of the present invention may include grow lights (light-emitting devices) for horticultural lighting, comprising one or more broadband solid-state light sources that produce a peak emission wavelength λ. pe Broadband light ranging from 400 nm to 520 nm (blue to cyan) with a free wave size (FWHM) of 30 nm to 60 nm. The peak emission wavelength can be selected to correspond to the peak absorption wavelength of chlorophyll and / or carotenoids to promote photosynthesis and plant growth.

[0153] The broadband blue solid-state light source Dev.3 is a broadband solid-state light source used in this invention to promote photosynthesis involving chlorophyll a. Dev.3 includes a broadband InGaN / GaN LED comprising multiple quantum wells (MQWs) that generate narrowband blue emission at different wavelengths. These quantum wells, when combined, produce broadband emission with a peak emission wavelength corresponding to the peak absorption wavelength of chlorophyll a (approximately 430 nm) in the blue region of the spectrum.

[0154] Table 3 presents the optical characteristics of the broadband blue solid-state light source Dev.3. As can be seen from the table, Dev.3 has a peak emission wavelength λ of approximately 432 nm. pe And approximately 38nm FWHM.

[0155] Figure 5 The diagram shows the spectral power distribution (SPD) of Dev.3 (solid line - Dev.3) as a function of wavelength (nm), and the SPD of light absorbed by chlorophyll a (dashed line - Dev.3). Chl-a ). Chlorophyll a (Dev.3) Chl-a The SPD of absorbed light was obtained by scaling the spectral power value of the SPD of Dev.3 using the normalized absorption spectrum of Chl-a. The normalized absorption spectrum of Chl-a is the absorption spectrum of Chl-a normalized so that its maximum absorbance value equals 1. Therefore, in order to obtain the absolute spectral power value absorbed by chlorophyll a, the spectral power value should be scaled by a ratio of 0.66. For comparison, Figure 5 It also includes the normalized absorption spectrum (dotted line - Chl-a) of chlorophyll a, showing the change of its normalized absorption factor with wavelength.

[0156] Photosynthetic photon flux (PPF) generated by Dev.3 Dev.3 The concentration was 0.3464 μmol / s. Chl-a absorbed PPF, PPF Chl-a The photosynthetic factor (PPF) is 0.1379 μmol / s. Chl-a / PPF Dev.3 The value is 40%. In Table 3, the values ​​in parentheses are calculated using normalized absorption spectroscopy. The photosynthetic photon efficiency (PPE) of Dev.3 is 2.0149 μmol / J.

[0157]

[0158] The broadband blue solid-state light source Dev.4 is a solid-state light source in this invention for promoting photosynthesis involving chlorophyll b. Dev.4 includes a broadband InGaN / GaN LED comprising multiple quantum wells (QWs) that generate narrowband components of different wavelengths. These components combine to produce broadband emission with a peak emission wavelength corresponding to the peak absorption wavelength of chlorophyll b (approximately 465 nm) in the blue region of the spectrum.

[0159] Table 4 presents the optical characteristics of the broadband blue solid-state light source Dev.4. As can be seen from the table, Dev.4 has a peak emission wavelength λ of approximately 462 nm. pe And approximately 41nm FWHM.

[0160] Figure 6 The diagram shows the spectral power distribution (SPD) of Dev.4 (solid line - Dev.4) as a function of wavelength (nm), and the SPD of light absorbed by chlorophyll b (dashed line - Dev.4). Chl-b ). Chlorophyll b (Dev.4) Chl-b The SPD of absorbed light was obtained by scaling the spectral power value of the Dev.4 SPD using the normalized absorption spectrum of Chl-b. The normalized absorption spectrum of Chl-b is the absorption spectrum that has been normalized so that its maximum absorbance value equals 1. Therefore, to obtain the absolute spectral power value of chlorophyll b absorption, the spectral power value should be scaled by 0.85. For comparison, Figure 6 It also includes the normalized absorption spectrum (dotted line - Chl-b) of chlorophyll b as a function of wavelength.

[0161] Photosynthetic photon flux (PPF) generated by Dev.4 Dev.4 The concentration of PPF absorbed by Chl-b is 0.3503 μmol / s. Chl-b The photosynthetic factor (PPF) is 0.2025 μmol / s. Chl-b / PPF Dev.4 The value is 58%. In Table 4, the values ​​in parentheses are calculated using normalized absorption spectroscopy. The photosynthetic photon efficiency (PPE) of Dev.4 is 2.0995 μmol / J.

[0162]

[0163] The broadband blue solid-state light source Dev.5 is a solid-state light source used in this invention to promote photosynthesis involving carotenoids. Dev.5 includes a broadband InGaN / GaN LED comprising multiple quantum wells (QWs) that generate narrowband components of different wavelengths. These components, when combined, produce a broadband emission peak whose peak emission wavelength corresponds to the peak absorption wavelengths of carotenoids (approximately 457 nm and approximately 487 nm).

[0164] Table 5 presents the measured optical characteristics of the broadband solid-state light source Dev.5. As can be seen from the table, the maximum emission peak wavelength λ of Dev.5 is... pe It is approximately 495nm, while FWHM is approximately 56nm.

[0165] Figure 7 The diagram shows the spectral power distribution (SPD) of Dev.5 (solid line - Dev.5) as a function of wavelength (nm), and the SPD of light absorbed by carotenoids (dashed line - Dev.5). Caro Carotenoids (Dev.5) Caro The SPD of the absorbed light was obtained by scaling the spectral power value of the Dev.5 SPD using the normalized absorption spectrum of Caro. The normalized absorption spectrum of Caro is the absorption spectrum of Caro normalized so that its maximum absorbance equals 1. Therefore, to obtain the absolute spectral power value absorbed by carotenoids, the spectral power value should be scaled by 0.62. For comparison, Figure 7 This also includes the absorption spectrum (dotted line - Caro) of carotenoids, showing how their absorption rate changes with wavelength. From... Figure 7 It can be seen that Dev.5 produces a second broadband peak at 467nm, and the FWHM is about 25nm.

[0166] Photosynthetic photon flux (PPF) generated by Dev.5 Dev.5 The concentration of PPF absorbed by Caro is 0.2221 μmol / s. Caro The photosynthetic factor (PPF) is 0.1027 μmol / s. Caro / PPF Dev.5 The value is 47%. In Table 5, the values ​​in parentheses are calculated using normalized absorption spectroscopy. The photosynthetic photon efficiency (PPE) of Dev.5 is 1.4246 μmol / J.

[0167]

[0168]

[0169] In other embodiments, the solid-state light source for carotenoids may include two broadband LEDs that produce light with a peak emission wavelength corresponding to the peak absorption wavelength of a corresponding carotenoid.

[0170] White light growth lamp: Broadband blue solid-state light source

[0171] Dev.6 is a white light-emitting device (growth lamp) of the present invention that utilizes a broadband blue solid-state light source to promote photosynthesis involving chlorophyll a. The broadband solid-state light source includes a broadband InGaN / GaN LED comprising multiple quantum wells (MQWs) that generate narrowband components of different wavelengths. These components combine to produce broadband emission with a peak emission wavelength corresponding to the peak absorption wavelength of chlorophyll a (approximately 430 nm) in the blue region of the spectrum.

[0172] White light emission device Dev.6 may include, for example: Figure 2A and 2B The packaged device shown includes a 2835 SMD package containing a single broadband blue LED, a red photoluminescent material that produces light with peak emission wavelengths in the orange to red region of the spectrum (approximately 640 nm to approximately 675 nm), corresponding to the red absorption peak of chlorophyll a, and a green to yellow photoluminescent material that produces light with peak emission wavelengths in the green to yellow region of the spectrum (approximately 540 nm to approximately 600 nm). More specifically, Dev.6 includes a general formula of CaAlSiN3:Eu 2+ The device employs a calcium silicon aluminum nitride phosphor (CASN) with a peak emission wavelength of approximately 615 nm, and a YAG-based phosphor with a peak emission wavelength of approximately 540 nm to 560 nm. In operation, the light-emitting device Dev.6 produces white light, which comprises a combination of blue light generated by a solid-state light source and yellow and red light generated by the phosphor materials.

[0173] Figure 8 The diagram shows the spectral power distribution of the white light emitting device (growth lamp) Dev.6 (solid line - Dev.6) as a function of wavelength (nm), and the absorption spectrum of chlorophyll a (dotted line - Chl-a) as a function of wavelength (nm). Figure 9 The diagram shows the spectral power distribution of Dev.6 (solid line - Dev.6) as a function of wavelength (nm) and the McCree curve (dashed line - McCree). From Figure 9 It can be seen that the white light generated by Dev.6 has a spectral composition whose shape essentially matches the McCree curve. This consistency in spectral composition promotes photosynthesis and increases the device's PPF efficiency.

[0174] Growth lamps including broadband full-spectrum blue solid-state light sources

[0175] As described herein, embodiments of the invention may include a light-emitting device (grow light) for horticultural lighting, the light-emitting device comprising a full-spectrum blue solid-state light source that produces light with a spectral composition more closely resembling (similar to) sunlight / daylight at wavelengths in the blue to cyan region of the spectrum (more specifically, at wavelengths of 400 nm to 520 nm for photosynthetically active radiation (PAR). More specifically, the broadband full-spectrum blue light has a flat emission maximum and its intensity is substantially constant (varying less than about 10%) over a wavelength range of at least 40 nm. The full-spectrum blue solid-state light source may include multiple broadband solid-state light sources.

[0176] The full-spectrum blue solid-state light source Dev.7 is a full-spectrum blue light source used in this invention to promote photosynthesis involving chlorophyll a (Chl-a) and chlorophyll b (Chl-b). Dev.7 comprises a combination of two InGaN / GaN MQW broadband blue LEDs. The first broadband LED produces blue light with a peak emission wavelength of 432 nm. The second broadband LED produces blue light with a peak emission wavelength of 451 nm. The peak emission wavelengths of the broadband blue LEDs are selected such that Dev.7 has a peak emission wavelength between the peak absorption wavelengths of chlorophyll a and chlorophyll b (430 nm and 465 nm).

[0177] A significant advantage of using a single broadband MQW LED chip to generate broadband blue light compared to using multiple narrowband blue LED chips is the substantial reduction in the number of LEDs required to produce broadband blue light emission. This is particularly important in horticultural applications, where the most popular SMD (surface mount device) packages, 2835 or 3030, have a square emitting area of ​​approximately 6 mm and can accommodate one to three LED chips, such as three medium-power chips or one high-power chip. The maximum FWHM achievable with three narrowband blue LED chips is approximately 45 nm. While large form factor packages such as chip-on-board (COB) can achieve a larger FWHM using three or more chips, such packages are incompatible with the linear area lighting required in horticultural applications. Furthermore, the bonding of multiple chips in package manufacturing increases costs and reduces productivity.

[0178] Table 6 presents the optical characteristics of the broadband full-spectrum blue solid-state light source Dev.6. As can be seen from the table, the maximum emission peak of Dev.7 is located at a peak emission wavelength of approximately 448 nm. pe FWHM is approximately 64nm. Figure 10The diagram shows the spectral power distribution (SPD) of Dev.7 (solid line - Dev.7) as a function of wavelength (nm), and the normalized absorption spectra of chlorophyll a (dotted line - Chl-a) and chlorophyll b (dashed line - Chl-b) as a function of wavelength (nm). Figure 10 It can be seen that the spectral power distribution of the light generated by Dev.7 includes broadband emission with a flat (clipping) emission maximum of 60, and its spectral power is essentially constant for wavelengths from about 430 nm to about 470 nm (with a variation of less than about 10%).

[0179] Figure 11 The image shows chlorophyll a (solid line - Dev.7). Chl-a The spectral power distribution (SPD) of absorbed light, where the spectral power (W / nm) varies with wavelength (nm). Chlorophyll a (Dev. 7) Chl-a The SPD of absorbed light was obtained by scaling the spectral power value of the Dev.7 SPD using the normalized absorption spectrum of Chl-a. The normalized absorption spectrum of Chl-a is the absorption spectrum of Chl-a normalized to have a maximum absorbance value equal to 1. Therefore, to obtain the absolute spectral power value absorbed by chlorophyll a, the spectral power value should be scaled by a ratio of 0.66. For comparison, Figure 11 It also includes the normalized absorption spectrum of chlorophyll a (dotted-line - Chl-a) as a function of wavelength.

[0180] Figure 12 The image shows chlorophyll b (solid line - Dev.7). Chl-b The spectral power distribution (SPD) of absorbed light, where the spectral power (W / nm) varies with wavelength (nm). Chlorophyll b (Dev. 7) Chl-b The SPD of absorbed light was obtained by scaling the spectral power value of the Dev.7 SPD using the normalized absorption spectrum of Chl-b. The normalized absorption spectrum of Chl-b is the absorption spectrum of Chl-b normalized so that its maximum absorbance value equals 1. Therefore, to obtain the absolute spectral power value of chlorophyll b absorption, the spectral power value should be scaled by a ratio of 0.85. For comparison, Figure 12 It also includes the absorption spectrum of chlorophyll b (dashed line -Chl-b) as its absorption factor changes with wavelength.

[0181] The photosynthetic photon flux (PPF) generated by Dev.7 Dev.7 The photosynthetic photon efficiency (PPE) is 0.6370 μmol / s, and the PPE is 1.9076 μmol / J. Chl-a absorbs PPF, PPF Chl-aThe photosynthetic factor (PPF) of Chl-a is 0.1790 μmol / s. Chl-a / PPF Dev.7 The photosynthetic factor (PPF) of Chl-b was 28%. The PPF absorbed by Chl-b was 0.3391 μmol / s. Chl-b / PPF Dev.7 The photosynthetic factor (PPF) of Caro was 53%. Caro absorbed 0.2917 μmol / s of PPF. Caro / PPF Dev.7 The value is 46%. In Table 6, the values ​​in parentheses are calculated using normalized absorption spectroscopy.

[0182]

[0183]

[0184] Purple grow light: Broadband full-spectrum blue solid-state light source

[0185] Dev.8 is a purple light-emitting device (growth lamp) of this invention that utilizes a broadband full-spectrum blue solid-state light source to promote photosynthesis involving chlorophyll a and chlorophyll b. The full-spectrum solid-state light source comprises a combination of two InGaN / GaN MQW broadband blue LEDs. The first broadband LED produces blue light with a peak emission wavelength of 432 nm. The second broadband LED produces blue light with a peak emission wavelength of 451 nm. The peak emission wavelengths of the broadband blue LEDs are selected such that Dev.8 has a peak emission wavelength between the peak absorption wavelengths of chlorophyll a and chlorophyll b (430 nm and 465 nm).

[0186] The purple light-emitting device Dev.8 comprises a 2835 SMD package containing two broadband blue LEDs and a red photoluminescent material. The peak emission wavelength of the light it produces falls within the orange to red region (approximately 640 nm to approximately 675 nm) of the spectrum corresponding to the red absorption peaks of chlorophyll a and chlorophyll b. More specifically, Dev.8 comprises materials of the general formula CaAlSiN3:Eu 2+ The calcium aluminum silicon nitride phosphor (CASN) has a peak emission wavelength of 660 nm. The light-emitting device Dev.8 produces purple light, which is a combination of blue light generated by a solid-state light source and red light generated by a red phosphor.

[0187] Figure 13The absorption spectra of photosynthetic pigments (i) chlorophyll a (dotted line - Chl-a) and (ii) chlorophyll b (dashed line - Chl-b) with their absorptivity (%) as a function of wavelength (nm) are shown, as well as the spectral power distribution of the purple grow lamp (light-emitting device) Dev.8 (solid line - Dev.8) with its spectral power as a function of wavelength (nm).

[0188] Figure 14 The image shows the spectral power distribution and PAS (thick solid line - PAS) of Dev.8 (thin solid line - Dev.8) as a function of wavelength (nm). From Figure 14 It can be seen that the light generated by Dev.8 has a spectral composition whose shape essentially matches that of PAS. This correspondence in spectral composition not only promotes photosynthesis but also improves the PPF efficiency of the light-emitting device.

[0189] White light growth lamp: Broadband full-spectrum blue solid-state light source

[0190] Dev.9 is a white light-emitting device (growth lamp) in this invention that utilizes a broadband full-spectrum blue solid-state light source to promote photosynthesis involving chlorophyll and carotenoids. The full-spectrum solid-state light source comprises a combination of two InGaN / GaN MQW broadband LEDs. The first broadband LED produces blue light with a peak emission wavelength of 432 nm. The second broadband LED produces blue light with a peak emission wavelength of 451 nm.

[0191] The white light-emitting device Dev.9 includes a 2835 SMD package containing two broadband blue LEDs, a red photoluminescent material that produces light with a peak emission wavelength in the orange to red region of the spectrum (approximately 640 nm to approximately 675 nm) corresponding to the red light absorption peak of chlorophyll a, and a green to yellow photoluminescent material that produces light with a peak emission wavelength in the green to yellow region of the spectrum (approximately 540 nm to approximately 600 nm). More specifically, Dev.9 includes a material with the general formula CaAlSiN3:Eu 2+ The device utilizes a calcium aluminum silicon nitride phosphor (CASN) with a peak emission wavelength of 650 nm, and a YAG-based phosphor with a peak emission wavelength of 510 nm to 570 nm. The Dev.9 light-emitting device produces white light with a correlated color temperature (CCT) of approximately 4000 K, which comprises a combination of broadband full-spectrum blue light generated by a solid-state light source and green to red light generated by photoluminescent materials. The combination of a broadband blue light with a WHM greater than approximately 30 nm and a cyan-emitting phosphor with a peak emission wavelength of 510 nm to 530 nm is important for producing light that simulates (very similar to) sunlight.

[0192] Figure 15The diagram shows the emission spectrum of a white light-emitting device (grow lamp) Dev.9 (solid line - Dev.9) using a full-spectrum white light solid-state light source, its normalized intensity as a function of wavelength (nm); the Planck trajectory (dashed line - 4000K BBL) of its normalized intensity as a function of wavelength (nm) at 4000K (CCT - blackbody trajectory - BBL); and the McCree curve (dotted line - McCree). Figure 15 It can be seen that, for wavelengths from approximately 420 nm to approximately 650 nm, the white light produced by Dev.9 has a spectral composition that essentially matches the Planck trajectory of a blackbody radiator at 4000 K, indicating that the light is very similar to sunlight (4000 K). Furthermore, it can be seen that the white light produced by Dev.9 has a spectral composition whose shape closely matches the shape of the McCree curve. This correspondence between the spectral composition and the McCree curve suggests that Dev.9 can increase the photosynthetically effective yield of plants.

[0193] In various embodiments of the invention, particularly those utilizing broadband and broadband full-spectrum blue solid-state light sources, the grow lamp (light-emitting device) advantageously produces light whose spectral composition matches (or is similar to) the PAS or McCree curve in the blue region of the spectrum.

[0194] like Figure 14 and 16 As shown, when this broadband full-spectrum blue emission is used together with a red phosphor with an emission peak wavelength of approximately 660 nm, the violet light produced by the growth lamp closely matches that of PAS. For comparison, Figure 16 The spectral power distribution of the purple growth lamp as a function of wavelength (nm) utilizes: (i) a narrowband blue solid-state light source (dotted line - narrowband blue) and (ii) a broadband blue solid-state light source (dashed line - broadband blue). It should be noted that each light source produces blue light with the same photon energy (the region under the curve). From... Figure 16 It can be seen that the growth lamps utilizing narrowband and broadband blue solid-state light sources have emission spectra with peak values ​​far exceeding those of PAS. This is because, compared to broadband full-spectrum light sources, their photon energy is distributed over a shorter wavelength range. The very broad emission spectrum of broadband full-spectrum light, where light energy is distributed over a larger wavelength range, leads to increased photosynthesis.

[0195] like Figure 16 As shown, when this broadband full-spectrum blue emission is used in conjunction with a broadband white conversion phosphor material (cyan to red), the white light generated by the growth lamp from approximately 500 nm to 660 nm is essentially matched to the McCree curve.

[0196] Growing lights including broadband blue light emission devices

[0197] According to various aspects of the present invention, a purple growth lamp, such as a linear growth lamp, is provided, which may include a combination of one or more broadband blue light emitting devices and one or more broadband red light emitting devices of the present invention. In some embodiments, the broadband blue light emitting device and the broadband red light emitting device include an encapsulation device.

[0198] Figure 17A and 17B This is a schematic diagram of a growth lamp 200 of the present invention, such as a T8 linear lamp. Each growth lamp 200 may include a linear (elongated) substrate 210, such as a metal core printed circuit board (MCPCB), having a plurality of packaged broadband light-emitting devices 220 mounted along its length. As shown, the light-emitting devices 220 may be arranged in a linear array extending in the extension direction of the substrate.

[0199] The light-emitting device 220 may include: (i) a broadband blue light-emitting device (blue Chl-a LED) 220a whose peak emission wavelength (e.g., about 420 nm to 440 nm) substantially matches the absorption peak of chlorophyll a (Chl-a); (ii) a broadband blue light-emitting device (blue Chl-b LED) 220b whose peak emission wavelength (e.g., about 460 nm to 470 nm) substantially matches the absorption peak of chlorophyll b (Chl-b); or (iii) a broadband red light-emitting device (red Chl LED) 220r whose peak emission wavelength (e.g., about 640 nm to about 675 nm) substantially matches the absorption peaks of chlorophyll a (Chl-a) and chlorophyll b (Chl-b) in the red region of the spectrum.

[0200] Blue Chl-a LED 220a and blue Chl-b LED 220b may include, for example, Figure 2A and 2B The packaged light-emitting device 100 includes two MQW broadband LED chips 118. The peak emission wavelengths of the MQW broadband LED chips 118 may be the same or different.

[0201] Red Chl LED 220r, for example, may include based on Figure 2A and 2B The packaged light-emitting device 100 is a packaged phosphor-converted red LED (PC red LED). For the red light-emitting device 220r, the packaged light-emitting device 100 typically includes two narrow-band blue LED chips 118, and the cavity 116 of the package 112 is filled with a light-transmitting medium 122 containing a red photoluminescent material. The red photoluminescent material produces light with peak emission wavelengths in the orange to red region of the spectrum (from about 640 nm to about 675 nm), which corresponds to the red absorption peaks of chlorophyll a and chlorophyll b (i.e., Figure 1A(10b and 20b). In some embodiments, the red photoluminescent material may include the general formula CaAlSiN3:Eu 2+ The calcium aluminum silicon nitride phosphor (CASN) has a peak emission wavelength of approximately 660 nm.

[0202] The photosynthetic photon flux (PPF) of blue Chl-a LEDs, blue Chl-b LEDs, and red Chl LEDs is basically the same, that is, photon flux: the total number of photons (photons) generated per second by each light source is basically the same.

[0203] The inventors have determined that by appropriately selecting the ratio of blue Chl LEDs (Chl-a + Chl-b) to red Chl LEDs, and more specifically, by appropriately selecting the number of blue photons (i.e., the blue photon flux PF at wavelengths in the blue region of the spectrum), Blue The ratio of blue Chl-a LEDs to blue Chl-b LEDs, and more specifically, the ratio of blue Chl-a LEDs to blue Chl-b LEDs, can provide grow lights optimized for a given application. This allows for the provision of grow lights optimized for specific applications, such as those promoting photosynthesis or providing single-source illumination for promoting plant growth or flowering.

[0204] Figure 17A The grow lamp 200 includes multiple blue Chl-a LEDs 220a and red Chl LEDs 220r. As shown in the figure, the ratio of the number of blue Chl-a LEDs 220a to the number of red Chl LEDs 220r is 1:1. With an equal number of blue and red Chl LEDs and each LED emitting substantially the same number of photons per second (i.e., they have substantially the same photon flux), the spectral composition of the light produced by the grow lamp shows that the number of blue photons (blue photon flux PF) is... Blue ) and the number of red photons (red photon flux PF) Red The ratio of blue Chl-a photons to red Chl photons is approximately 1:1 (1.0 ± 0.3: 1.0). The inventors have determined that a growth lamp with a spectrum having substantially equal photon numbers (photon flux) including blue Chl-a photons and red Chl photons can promote photosynthesis. It should be understood that in other settings, different ratios of blue Chl-a photons to red Chl photons can be used.

[0205] refer to Figure 17B The grow lamp 200 includes multiple blue Chl-a LEDs 220a, blue Chl-b LEDs 220b, and red Chl LEDs 220r. As shown in the figure, the ratio of the number of blue Chl-a LEDs and Chl-b LEDs 220a, 220b to the number of red Chl LEDs 220r is 1:1. Given that each LED emits substantially the same total number of photons per second (i.e., they have substantially the same photon flux), the spectral composition of the light produced by the grow lamp contains a significant number of blue photons (blue photon flux PF). Blue ) and the number of red photons (red photon flux PF) Red The ratio of ) is approximately 1:1 (1.0 ± 0.3: 1.0). The inventors have determined that it has blue Chl-a + blue Chl-b photons (blue photon flux PF) Blue ) and red Chl photons (red photon flux PF) Red Growth lamps with a spectrum that has approximately the same number of photons (photon flux) can promote photosynthesis.

[0206] In other settings, the number of blue photons (blue photon flux PF) Blue It can be greater than the number of red photons (red photon flux PF). Red For example, the ratio is approximately 3:1 (3.0 ± 0.5: 1.0). The inventors have determined that it includes a ratio of red photon number (red photon flux PF). Red More blue Chl-a+ and blue Chl-b photons (blue photon flux PF) Blue The number of blue photons (blue photon flux PF) Blue Growth lights with a specific spectrum can promote plant reproduction.

[0207] In other settings, the number of red photons (red photon flux PF) Red It can be greater than the number of blue photons (blue photon flux PF). Blue For example, the ratio is approximately 3:1 (3.0 ± 1.0: 1.0). The inventors have determined that it includes a ratio of more blue photons (blue photon flux PF). Blue A larger number of red photons (red photon flux PF) Red Growth lights with a specific spectrum can promote flowering.

[0208] Furthermore, in setups utilizing both blue Chl-a LEDs and blue Chl-b LEDs, the blue Chl-a photon count (blue photon flux PF) is significantly higher. Blue-Chl-a It can be greater than the number of blue Chl-b photons (blue photon flux PF). Blue-Chl-bFor example, the ratio is approximately 3:1 (3.0 ± 1.0: 1.0), meaning that about 75% of the blue light is produced by blue Chl-a LEDs.

[0209] Table 7 lists the photon flux ratios for different grow lamp applications.

[0210]

[0211]

[0212] Dev.10 is a solid-state blue light source (blue Chl-a LED) including the SMD 2835 packaged broadband blue light emitting device of the present invention, which includes two broadband MQW LEDs whose peak emission wavelength corresponds to the chlorophyll a (Chl-a) absorption peak.

[0213] Dev.11 is a solid-state blue light source (blue Chl-b LED) including a broadband blue light emitting device in an SMD 2835 package of the present invention, the device comprising two broadband MQW LEDs whose peak emission wavelength corresponds to the chlorophyll b (Chl-b) absorption peak.

[0214] Dev.12 is a solid-state red light source (red light Chl LED) that includes a PC red LED (red light Chl LED) in an SMD 2835 package. Its peak emission wavelength corresponds to the absorption peaks of chlorophyll a (Chl-a) and chlorophyll b (Chl-b) in the red region of the spectrum.

[0215] Each of the devices Dev.10 to Dev.12 is a 0.2W device with a 3V positive drive voltage.

[0216] Table 8 lists the measured optical characteristics of the packaged light-emitting devices Dev.10 to Dev.12. Figure 18 The radiative power spectrum of the broadband blue solid-state light source (blue Chl-a LED) Dev.10 (solid line - Dev.10) as a function of wavelength (nm) is shown, as well as the absorption spectrum of chlorophyll a (dotted line - Chl-a) as a function of wavelength (nm). Figure 19 The radiative power spectrum of the broadband blue solid-state light source (blue Chl-a LED) Dev.11 (solid line - Dev.11) as a function of wavelength (nm) is shown, as is the absorption spectrum of chlorophyll b (dotted line - Chl-b) as a function of wavelength (nm). Figure 20 The radiation power spectrum of the broadband red solid-state light source (red Chl LED) Dev.12 (solid line - Dev.12) is shown as the relative radiation power as a function of wavelength (nm).

[0217] As can be seen from Table 8, each of devices Dev.10 to Dev.12 has essentially the same PPF and PPE. (Reference) Figure 18 It should be noted that the emission spectrum of Dev.10 (blue Chl-a LED) is basically matched with that of Chl-a, with the first peak emission wavelength λ. pe The second peak emission wavelength is approximately 426 nm. pe Approximately 437nm, FWHM is approximately 27nm. (Reference) Figure 19 It should be noted that the Dev.11 (blue Chl-b LED) has an emission spectrum that is basically matched with Chl-b, with a peak emission wavelength λ. pe Approximately 462nm, FWHM is approximately 34nm. (Reference) Figure 20 It should be noted that the Dev.12 (red ChlLED) has a peak emission wavelength λ. pe The emission spectrum is approximately 660 nm with an FWHM of approximately 82 nm.

[0218]

[0219] The solid-state grow lights Dev.13 through Dev.15 all include T8 solid-state grow lights, which consist of a total of 108 broadband light sources (blue Chl-a-Dev.10, blue Chl-b-Dev.11, and red Chl-Dev.12). Dev.13 is used to promote photosynthesis, Dev.14 is used to promote photosynthesis through single-source illumination, and Dev.15 is configured to promote flowering.

[0220] Table 9 shows the composition of solid-state growth lamps Dev.13 to Dev.15. As can be seen from Table 9, Dev.13 includes 54 broadband blue Chl-a LEDs and 54 broadband red Chl LEDs. Assuming that the blue Chl-a LEDs and red Chl LEDs each emit approximately the same number of photons per second, the photon ratio of blue Chl-a to red Chl-a is 1:1.

[0221] As shown in Table 9, Dev.14 includes 48 broadband blue Chl-a LEDs, 8 broadband blue Chl-b LEDs, and 52 broadband red Chl LEDs. In this configuration, the ratio of blue photons (Chl-a + Chl-b) to red photons is 1:1. Regarding the composition of the blue light, the ratio of blue Chl-a to blue Chl-b photons is approximately 6:1 (48:8).

[0222] As shown in Table 9, Dev.15 includes 17 broadband blue Chl-a LEDs, 2 broadband blue Chl-b LEDs, and 89 broadband red Chl LEDs. In this configuration, the ratio of blue photon count (Chl-a + Chl-b) to red photon count is approximately 1:4 (13:55), meaning that the spectral composition of the light generated by Dev.15 is predominantly red in terms of photon count. Regarding the blue light composition, the ratio of blue Chl-a to blue Chl-b photon count is approximately 8:1 (17:2).

[0223]

[0224] Tables 10A and 10B list the measured optical characteristics of the grow lights Dev. 13 to Dev. 15. In Table 10A: PPF x-y It is the photosynthetic photon flux with a wavelength of xy nanometers; PPE x-y It is the photon flux efficiency at a wavelength of xy nanometers; PF x-y This is the photon flux (number of photons per second) at a wavelength of xy nanometers. In Table 10B: PPF Blue It is the photosynthetic photon flux of blue light with a wavelength of 400-500nm; PF Blue It is the photon flux (photons per second) of blue light with a wavelength of 400-500nm; PPF Red It is the photosynthetic photon flux of red light with a wavelength of 600-700nm; PF Blue It is the photon flux (number of photons per second) of blue light with a wavelength of 600-700nm.

[0225] Figure 21 The emission spectrum of the grow lamp Dev.13 (solid line - Dev.13) as a function of wavelength (nm) and the absorption spectrum of chlorophyll a (dotted line - Chl-a) as a function of wavelength (nm) are shown. Figure 22 The emission spectrum of the grow lamp Dev.14 (solid line - Dev.14) is shown as a function of normalized intensity and wavelength (nm). Figure 23 The emission spectrum of the grow lamp Dev.15 (solid line - Dev.15) is shown as a function of normalized intensity and wavelength (nm).

[0226]

[0227]

[0228]

[0229] As can be seen from Table 10A, the photosynthetic photon flux (PPF) of the growth lamp Dev.13 is... 400-700The photosynthetic photon efficiency (PPE) was 42.148 μmol / s. 400-700 The concentration is 1.7836 μmol / J. As can be seen from Table 10B, the blue area (PF...) Blue The photon flux (photons per second) in the red region (PF) Red The ratio of photon flux (photons per second) in the ) is approximately 1.3:1 (1.28:1).

[0230] As can be seen from Table 10A, the photosynthetic photon flux (PPF) of the growth lamp Dev.14 is... 400-700 The photosynthetic photon efficiency (PPE) was 42.850 μmol / s. 400-700 The concentration is 1.8063 μmol / J. As can be seen from Table 10B, the blue area (PF...) Blue The photon flux (photons per second) in the red region (PF) Red The ratio of photon flux (photons per second) in the ) is approximately 1.3:1 (1.29:1).

[0231] As can be seen from Table 10A, the photosynthetic photon flux (PPF) of the growth lamp Dev.15 is... 400-700 The photosynthetic photon efficiency (PPE) was 39.758 μmol / s. 400-700 The concentration is 1.7352 μmol / J. As can be seen from Table 10B, the blue area (PF...) Blue The photon flux (photons per second) in the red region (PF) Red The ratio of photon flux (photons per second) in the two components is approximately 1:3.

[0232] Although the aforementioned purple growth lamp has been described as utilizing a combination of one or more broadband blue light emitting devices and one or more broadband red light emitting devices according to embodiments of the present invention, it should be understood that the present invention also includes growth lamps utilizing a combination of one or more narrowband blue light emitting devices and one or more narrowband / broadband red light emitting devices; and growth lamps utilizing a combination of one or more narrowband / broadband red light emitting devices.

[0233] [Abbreviation Explanation]

[0234] BBL: Blackbody Track; Blue Chl-a LED: Blue light emitting device—its peak emission wavelength matches the blue absorption peak of chlorophyll a; Blue Chl-b LED: Blue light emitting device—its peak emission wavelength matches the blue absorption peak of chlorophyll b; Caro: Carotenoid; CASN: Calcium Aluminum Silicon Nitride; Chl-a: Chlorophyll a; Chl-b: Chlorophyll b; COB: On-Board Chip Package; FWHM: Full Horizon; LED: Light Emitting Diode; MQW: Multiple Quantum Well; PAR: Photosynthetically Active Radiation; PAS: Photosynthetic Spectrum; PC Red LED: Phosphor-Converted Red LED; PF: Photon Flux; PF x-y Photon flux at wavelength xy nanometers; PFD: Photon flux density; PPE: Photosynthetic photon efficiency (Kp); PPF: Photosynthetic photon flux; PPF x-y Photosynthetic photon flux at wavelength xy nanometers; Red Chl LED: Red light emitting device—its peak emission wavelength basically matches the red light absorption peak of chlorophyll; SPD: Spectral power distribution; YAG: Yttrium aluminum garnet.

[0235] [Explanation of Labels in the Attached Image]

[0236] 10a: Chlorophyll a (Chl-a) blue absorption peak; 10b: Chlorophyll a (Chl-a) red absorption peak; 20a: Chlorophyll b (Chl-b) blue absorption peak; 20b: Chlorophyll b (Chl-b) red absorption peak; 30a, 30b: Carotenoid (Caro) blue absorption peak; 40: Photosynthetic Action Spectrum (PAS) blue peak; 50: Photosynthetic Action Spectrum (PAS) red peak; 100: Light-emitting device; 110: Encapsulation; 112: Encapsulation base; 114: Encapsulation sidewall; 116: Cavity; 118: LED chip; 120: Bonding wire; 122: Contact pad; 124: Transmitting material; 200: Growth lamp; 210: Substrate; 220: Light-emitting device; 220a: Blue Chl-a LED; 220b: Blue Chl-b LED; 220r: Red Chl LED.

Claims

1. A growth light, characterized in that, include: Broadband blue solid-state light source, which produces blue light with blue photon flux; as well as A red solid-state light source that produces red light with a red photon flux; The ratio of the blue photon flux to the red photon flux is in the range of 0.3:1 to 3:

1. The broadband blue solid-state light source includes a broadband InGaN / GaN multi-quantum-well LED chip, which contains multiple quantum wells of different wavelengths in its active region to generate multiple narrowband blue to cyan light emission of multiple different wavelengths. The broadband blue solid-state light source is used to generate broadband blue light with a peak emission wavelength between 420 nm and 495 nm, and the broadband blue solid-state light source is used to generate light with an emission intensity variation of less than 15% in a wavelength range of at least 40 nm. The broadband blue light is composed of a combination of the multiple narrowband blue-to-cyan light emissions; and the broadband blue light has a larger full width at half maximum (FWHM) compared to the narrowband blue-to-cyan light emissions.

2. The growth lamp according to claim 1, characterized in that, The ratio of the blue photon flux to the red photon flux is 1:

1.

3. The growth lamp according to claim 1, characterized in that, The broadband blue light is essentially compatible with at least one of the following: The absorption peak wavelength of chlorophyll a; The absorption peak wavelength of chlorophyll b; and The absorption peak wavelength of carotenoids.

4. The growth lamp according to claim 3, characterized in that, The peak emission wavelength of the broadband blue light is at least one of the following: From 420nm to 450nm; From 460nm to 480nm; From 450nm to 465nm; From 480nm to 495nm.

5. The growth lamp according to claim 1, characterized in that, The broadband blue solid-state light source generates a first broadband blue light from 420 nm to 450 nm with a first blue photon flux and a second broadband blue light from 460 nm to 470 nm with a second blue photon flux, wherein the ratio of the first blue photon flux to the second blue photon flux is in the range of 2:1 to 4:

1.

6. The growth lamp according to claim 1, characterized in that, The red solid-state light source includes a narrow-band blue LED and a red photoluminescent material.

7. The growth lamp according to claim 1, characterized in that, Also includes: Far-red solid-state light sources or red photoluminescent materials produce red light with a peak emission wavelength of 680nm to 780nm.

8. The growth lamp according to claim 1, characterized in that, The broadband blue light has a full width at half maximum (FWHM) of at least 30 nm or between 30 nm and 80 nm.

9. A light-emitting device for plant cultivation, characterized in that, include: The first solid-state light source is used to generate blue light with a blue photon flux. as well as The second solid-state light source is used to generate red light with red photon flux; The ratio of the blue photon flux to the red photon flux is in the range of 1:3 to 3:

1. The first solid-state light source is used to generate a first broadband blue light with a peak emission wavelength between 420 nm and 450 nm having a first blue photon flux, and a second broadband blue light with a peak emission wavelength between 460 nm and 470 nm having a second blue photon flux, wherein the ratio of the first blue photon flux to the second blue photon flux is in the range of 2:1 to 4:

1. The first solid-state light source includes a broadband blue solid-state light source, which is used to generate broadband blue light with a peak emission wavelength between 420 nm and 495 nm, and the broadband blue solid-state light source is used to generate light with an emission intensity variation of less than 15% in a wavelength range of at least 40 nm.

10. The light-emitting device for plant cultivation according to claim 9, characterized in that, The ratio of the blue photon flux to the red photon flux can be at least one of the following: 1:1, 3:1, or 1:

3.

11. The light-emitting device for plant cultivation according to claim 9, characterized in that, The peak emission wavelength of the blue light generated by the first solid-state light source is at least one of the following: 420 nm to 450 nm; 460 nm to 480 nm; 450 nm to 465 nm; 480 nm to 495 nm.

12. The light-emitting device for plant cultivation according to claim 11, characterized in that, The first solid-state light source includes multiple narrowband blue LEDs, which are used to generate multiple narrowband blue light with different peak emission wavelengths.

13. The light-emitting device for plant cultivation according to claim 9, characterized in that, The second solid-state light source includes a narrow-band blue LED and a red photoluminescent material.

14. The light-emitting device for plant cultivation according to claim 9, characterized in that, The light-emitting device also includes a red solid-state light source or a photoluminescent material, which is used to generate red light with a peak emission wavelength between 680 nm and 780 nm.

15. The light-emitting device for plant cultivation according to claim 9, characterized in that, The full width at half maximum (FWHM) of the blue light is at least one of the following: at least 40 nm; at least 50 nm; at least 60 nm; or 40 nm to 80 nm.

16. A light-emitting device for plant cultivation, characterized in that, include: A broadband blue solid-state light source for generating broadband blue light with peak emission wavelengths between 420 nm and 495 nm; The broadband blue solid-state light source is used to generate light with an emission intensity variation of less than 15% in a wavelength range of at least 40 nm.

17. The light-emitting device for plant cultivation according to claim 16, characterized in that, The change in emission intensity is less than 10%.

18. The light-emitting device for plant cultivation according to claim 16, characterized in that, The emission intensity changes by less than 15% from 430 nm to 470 nm.

19. The light-emitting device for plant cultivation according to claim 16, characterized in that, The emission intensity changes by less than 10% from 430 nm to 470 nm.

20. The light-emitting device for plant cultivation according to claim 16, characterized in that, The broadband blue solid-state light source includes a broadband InGaN / GaN multi-quantum-well LED chip, which contains multiple quantum wells of different wavelengths in its active region to generate the emission of multiple narrowband blue to cyan light of different wavelengths.

21. The light-emitting device for plant cultivation according to claim 16, characterized in that, The broadband blue light is composed of a combination of multiple narrowband blue light to cyan light emission.

22. The light-emitting device for plant cultivation according to claim 16, characterized in that, The light-emitting device also includes a red solid-state light source or a red photoluminescent material, which produces red light with a peak emission wavelength between 630 nm and 680 nm.

23. The light-emitting device for plant cultivation according to claim 16, characterized in that, The light-emitting device also includes a far-red solid-state light source or a far-red photoluminescent material, which generates far-red light with a peak emission wavelength between 630 nm and 780 nm.

24. The light-emitting device for plant cultivation according to claim 16, characterized in that, The light-emitting device further includes at least one of the following: a green to yellow photoluminescent material that generates green to yellow light with a peak emission wavelength between 540 nm and 600 nm; and a cyan to red photoluminescent material that generates cyan to red light with a peak emission wavelength between 500 nm and 680 nm.

25. The light-emitting device for plant cultivation according to claim 16, characterized in that, The broadband blue light has a full width at half maximum (FWHM) of at least 30 nm or between 30 nm and 80 nm.

26. The light-emitting device for plant cultivation according to claim 16, characterized in that, The emission intensity is essentially constant.

27. The light-emitting device for plant cultivation according to claim 16, characterized in that, The light-emitting device includes multiple broadband blue solid-state light sources.

28. The light-emitting device for plant cultivation according to claim 16, characterized in that, The light-emitting device includes a growth lamp.

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