Cultivating methods and apparatuses
A cultivator for damaging undesirable plants in an agricultural setting is disclosed. Embodiments of the cultivator include one or more energy emitters that stress target biological material, and the energy emitters in particular embodiments stress plants in at least two different ways, such as imparting light at certain wavelengths that cause dual effect stressors to the plant, such as heat related stress and photochemical stress similar to a sunburn. Some embodiments include a focusing system that spreads out narrow light beams and/or brings multiple light beams together at a point that is outside the cultivator. Some focusing systems cause multiple light beams to initially diverge before converging. Some embodiments utilize unusually large mirrors to capture, for example, multiple light pathways, and direct them to the target. Advantages include the ability to accomplish weeding and/or thinning with very low overall power consumption while moving quickly through a field.
1 . A cultivator, comprising:
a light emitter producing blue light with wavelengths from 365 nm to 488 nm;
a focusing device receiving light from the light emitter and focusing the light at a focus distance from the focusing device;
a light director positioned a distance from the focusing device and receiving light from the focusing device, the light director sequentially redirecting the light toward multiple target plants; and
a target tracking system configured to identify and track the multiple target plants,
wherein
the focus distance is greater than the distance from the focusing device to the light director,
the light director receives information from the target tracking system to maintain the light on one of the multiple target plants for 25 ms to 300 ms,
the optical power intensity of the light at the one of the multiple target plants is from 300 W/cm 2 to 1,000 W/cm 2 , and
wherein the light pathway forms a spot size at the focus distance of approximately 12 mm 2 .
2 . The cultivator of claim 1 , wherein the light emitter includes an array of laser diodes.
3 . The cultivator of claim 2 , further comprising:
a first lens receiving light from the array of laser diodes and causing the light pathways from the laser diodes to diverge; and
a second lens receiving light from the first lens and causing the light pathways to converge.
4 . The cultivator of claim 3 , wherein the first lens causes the light pathways to expand.
5 . The cultivator of claim 4 , wherein at least one of the first lens and the second lens is a convex lens.
6 . The cultivator of claim 4 , wherein the light pathways form a spot size at the focus distance of approximately 12 mm 2 .
7 . The cultivator of claim 6 , wherein the power intensity of the light in the 12 mm 2 spot is 500-900 W/cm 2 .
8 . The cultivator of claim 1 , wherein the light emitter emits light at one or more wavelengths from 430 nm to 480 nm.
9 . The cultivator of claim 1 , wherein the focusing device expands the pathway in which the light travels.
10 . The cultivator of claim 1 , wherein the light director includes two reflectors and two motors, each motor including a rotator that rotates about a rotation axis, and each reflector is connected to a rotator.
11 . The cultivator of claim 10 , wherein the rotator of each motor is a motor housing.
12 . The cultivator of claim 10 , wherein the reflective area of each of the two reflectors are at least 3 square inches.
13 . The cultivator of claim 1 ,
wherein the light director receives information from the target tracking system to maintain the light on a leaf of the target plant for 100-200 ms.
14 . A cultivator, comprising:
means for generating light in two or more light pathways, wherein the light in each of the two or more light pathways has wavelengths from 365 nm to 488 nm;
means for focusing light propagating in the two or more light pathways at a focus distance; and
means for sequentially directing light propagating in the two or more pathways from the focusing means toward multiple target plants, wherein said means for sequentially directing includes maintaining the light on each of the multiple target plants for 25 ms to 300 ms;
wherein
the focus distance is greater than the distance from the focusing means to the light directing means,
the optical power intensity of the light is from 300 W/cm 2 to 1,000 W/cm 2 at the one of the multiple target plants and
the light pathways form a spot size at the focus distance of approximately 12 mm 2 .
15 . The cultivator of claim 14 , wherein the light generating means includes means for generating blue light in two or more light pathways at one or more wavelengths from 430 nm to 480 nm.
16 . The cultivator of claim 14 , wherein
the means for generating light includes an array of laser diodes, and
the light focusing means includes
a first lens receiving light from the array of laser diodes and causing the light pathways from the laser diodes to diverge and individually expand, and
a second lens receiving light from the first lens and causing the light pathways to converge.
17 . The cultivator of claim 16 , wherein
and the power intensity of the light onto the target plants spot is 500-900 W/cm 2 .
18 . The cultivator of claim 17 , wherein
the means for light directing includes two reflectors and two motors, each motor including a housing that rotates about a rotation axis, each reflector being connected to a rotator, and each of the reflectors having a reflective area of at least 3 square inches.
19 . The cultivator of claim 18 , further comprising:
a target tracking system configured to identify and track a target biological material,
wherein the light director receives information from the target tracking system to maintain the light on the target plant for 100-200 ms.