Patent Description:
Technologies of irradiating a target with high-power laser light to remotely destroying the target are researched. For example, Patent Literature <NUM> discloses a technology of irradiating high-power continuous wave laser light to destroy a target. An apparatus described in the Patent Literature <NUM> converts high-power continuous wave laser light to pulse laser light by pulse converter and irradiates the converted laser light to the target. An optical sensor receives reflected light of this laser light and detects the target. A controller stops pulse conversion process of the pulse converter so that continuous wave laser light is irradiated to the target and the target is destroyed.

In addition, a technology of changing irradiation direction of laser light non-mechanically is researched. For example, Patent Literature <NUM> discloses a technology of changing laser irradiation direction by wavelength. An apparatus described in the Patent Literature <NUM> is provided with a waveguide having two distributed Bragg reflection mirrors, a light incident port for incident light in the waveguide and a light emission port for emitting light that is guided in the waveguide.

Patent Literature <NUM> discloses a technology of changing irradiation direction of high-power laser non-mechanically. The apparatus disclosed in the Patent Literature <NUM> is provided with a first vertical cavity surface emitting laser (VCSEL) long in a first direction and a driving circuit that injects current to the first VCSEL. Incident light, that incidents in the incident port provided at an end in the first direction of the first VCSEL, travels inside the first VCSEL along the first direction, while being reflected in a vertical direction, and is emitted from the emitting port on an upper surface of the first VCSEL as emission light. It is disclosed that a direction in which this emission light is emitted is inclined to the first direction from a normal direction of the emitting port based on a wavelength of the incident light and the like.

The present invention has been made in view of the above circumstances and one objective thereof is to provide a laser irradiation apparatus that efficiently carries out processes such as detection of target by use of laser light. Other objectives will be understood from following disclosures and explanations of embodiments.

According to the present invention, a process such as detection of a target is efficiently carried out.

A laser irradiation apparatus <NUM> according to an example not falling under the scope of claim 1is configured to detect a target <NUM> by use of output laser light <NUM> and destroy the target <NUM>. As shown in <FIG>, the laser irradiation apparatus <NUM> is provided with a laser array <NUM>, a detector <NUM> and a controller <NUM>.

The laser array <NUM> is formed with a plurality of laser oscillators <NUM> that irradiate output laser light <NUM> and are arranged in an array on a surface thereof. For example, the laser oscillators <NUM> may be regularly arranged, in a grid pattern for example. The laser oscillator <NUM> may be arranged irregularly. The laser oscillators <NUM> are arranged in the laser array <NUM> at a high density: for example, <NUM> or more laser oscillators <NUM> are arranged per square meter. The laser oscillators <NUM> may be arranged at a density of ten thousand or more per square.

The laser oscillators <NUM> can arbitrarily change a direction of irradiating the output laser light <NUM>. For example, the laser oscillator <NUM> change the direction of irradiating the output laser light <NUM> non-mechanically and two-dimensionally. When a target <NUM> such as a drone exists on an optical axis of the output laser light <NUM> irradiated by the laser oscillator <NUM>, the target <NUM> reflects the output laser light <NUM> as reflected light <NUM>. Detail of the laser oscillator <NUM> will be described later.

The detector <NUM> receives the reflected light <NUM> reflected by the target <NUM> and obtains detection information such as an image in which the target <NUM> is taken. For example, the detector <NUM> includes an optical camera such as a visible ray camera, an infrared ray camera and an ultraviolet ray camera, and takes an image of the target <NUM> irradiated by the output laser light <NUM>. The detector <NUM> obtains an image in which the target <NUM> is taken as detection information and transmits it to the controller <NUM>. The detector <NUM> may select an arbitrary device to detect the reflected light <NUM>.

The controller <NUM> estimates a position of the target <NUM> based on the detection information such as the image obtained by the detector <NUM>. The controller <NUM> extracts a location in the image taken by the detector <NUM> where the target <NUM> is shown. The controller <NUM> estimates the position of the target <NUM> based on the direction in which the detector <NUM> has taken the image and the location where the target <NUM> is shown in the image that has been taken. The controller <NUM> transmits to the plurality of laser oscillators <NUM> a request to irradiate the output laser light <NUM> to the estimated position of the target <NUM>.

The plurality of laser oscillators <NUM> irradiate the output laser light <NUM> to the estimated positions of the target <NUM>. For example, all of the laser oscillators <NUM> that can irradiate to the position of the target <NUM> may irradiate the output laser light <NUM> to the position of the target <NUM>. At the position of the target <NUM>, energy of the output laser light <NUM> is increased by overlaying the output laser light <NUM> irradiated by the plurality of laser oscillators <NUM>. As a result, the laser irradiation apparatus <NUM> can destroy the target <NUM>. For this reason, the output laser light <NUM> irradiated by the laser oscillators <NUM> may have phases that interfere so that energies of the output laser light <NUM> strengthen each other at the position of the target <NUM>. In this case, the phase of the output laser light <NUM> irradiated by each laser oscillator <NUM> is instructed by the controller <NUM>.

As described above, the laser irradiation apparatus <NUM> can irradiate output laser light <NUM> as detection laser light to detect a target <NUM> and irradiate to the target <NUM> a plurality of beams of the output laser light <NUM> as dealing laser light to attack the detected target <NUM>. For this reason, detection of the target <NUM> and attack on the target <NUM> can be efficiently performed. It should be noted that the laser array <NUM> may be provided with a laser oscillator <NUM> that can irradiate only detection laser light. In addition, the laser array <NUM> may be provided with a laser oscillator <NUM> that can irradiate only dealing laser light. All laser oscillators <NUM> included in the laser array <NUM> may be configured to be able to irradiate detection laser light and dealing laser light.

An operation of the laser irradiation apparatus <NUM> will be described in more detail. The laser irradiation apparatus <NUM> carries out processes shown in <FIG>. In step S100, the detector <NUM> starts a monitoring such as taking images for detecting the target <NUM> and obtains detection information. A direction in which the detector <NUM> detects, for example a direction of taking image, may be determined based on an instruction from the controller <NUM>. The direction in which the detector <NUM> detects may be fixed to a predetermined direction.

In step S110, a laser oscillator <NUM> irradiates output laser light <NUM> as detection laser light. The controller <NUM> determines the laser oscillator <NUM> which irradiates the detection laser light and generates a detection signal which indicates to the determined laser oscillator <NUM> to irradiate the detection laser light. As the laser oscillator <NUM> that is to irradiate the detection laser light, one of the laser oscillators <NUM> that can irradiate detection laser light to a detection space <NUM> to be detected may be selectively determined. For example, as shown in <FIG>, the controller <NUM> transmits a detection signal to a first laser oscillator <NUM>-<NUM> and a second laser oscillator <NUM>-<NUM> of the plurality of laser oscillators <NUM>. A direction of irradiating the detection laser light is indicated in the detection signal. The first laser oscillator <NUM>-<NUM> irradiates detection laser light to a first detection space <NUM>-<NUM> based on the received detection signal. The second laser oscillator <NUM>-<NUM> irradiates detection laser light to a second detection space <NUM>-<NUM> based on the received detection signal. For example, the first detection space <NUM>-<NUM> and the second detection space <NUM>-<NUM> are different spaces. The first detection space <NUM>-<NUM> and the second detection space <NUM>-<NUM> may be overlapped or not overlapped. All laser oscillators <NUM> provided to the laser array <NUM> may irradiate detection laser light or a part of the laser oscillators <NUM> may irradiate detection laser light. A single laser oscillator <NUM> may irradiate detection laser light.

In step S120, the controller <NUM> determines whether information of the target <NUM> is included in the detection information obtained by the detector <NUM>. For example, the controller <NUM> determines that information of the target <NUM> is included when there is in an image taken by the detector <NUM> an area brighter than a predetermined threshold value. When it is determined that the information of the target <NUM> is included in the detection information, the process proceeds to step S130. When it is determined that the information of the target <NUM> is not included in the detection information, the process returns to step S110 and the process is repeated until the target <NUM> is detected.

In step S130, the controller <NUM> estimates a position of the target <NUM> based on the detection information. For example, when the laser irradiation apparatus <NUM> is provided with a plurality of detectors <NUM>, the controller <NUM> extracts the location in which the target <NUM> is shown from the image taken by each of the detectors <NUM>. A target direction <NUM> from the detector <NUM> toward the target <NUM> is estimated based on the extracted position of the target <NUM> and the direction in which the detector <NUM> takes image. As shown in <FIG>, the controller <NUM> estimates a location in which a straight line elongated along the target direction <NUM> from each detector <NUM> toward the target <NUM> crosses as the position of the target <NUM>.

For example, when the laser oscillator <NUM> irradiates pulse laser light as detection laser light, the controller <NUM> estimates a distance from the detector <NUM> to the target <NUM> based on a time from when the laser oscillator <NUM> irradiates the detection laser light to when the detector <NUM> receives reflected light <NUM>. The target direction <NUM> from the detector <NUM> toward the target <NUM> is estimated based on the detection information obtained by the detector <NUM>. The controller <NUM> estimates the position of the target <NUM> based on the distance from the detector <NUM> to the target <NUM> and the target direction <NUM>.

In step S140, the controller <NUM> controls the laser oscillator <NUM> and irradiates output laser light <NUM> as dealing laser light to the target <NUM>. The controller <NUM> determines a plurality of laser oscillators <NUM> that irradiate dealing laser light and transmits dealing signal for irradiating dealing laser light to the position of the target <NUM> estimated in step S130 to the determined plurality of laser oscillators <NUM>. The laser oscillators <NUM> are specified by the dealing signal in the direction of irradiating the dealing laser light and irradiate the dealing laser light in the specified direction. The dealing laser light irradiated by the laser oscillators <NUM> is overlayed on the target <NUM> and destroys the target <NUM>.

The laser oscillator <NUM> that irradiates the dealing laser light is determined based on the position of the target <NUM>. A laser oscillator <NUM> of the laser oscillators <NUM>, that can irradiate dealing laser light to the target <NUM>, irradiates the dealing laser light to the target <NUM>. For example, all of those laser oscillators <NUM> may irradiate the dealing laser light to the target <NUM>. In addition, a part of those laser oscillators <NUM>, for example laser oscillators <NUM> of which irradiation angle is equal to or less than <NUM> degrees, may irradiate the dealing laser light to the target <NUM>. The irradiation angle indicates an angle between a direction from a laser oscillator <NUM> toward a center of a space to which the laser oscillator <NUM> can irradiate output laser light <NUM> and an irradiation direction of the output laser light <NUM>. It should be noted that a laser oscillator <NUM> that does not irradiate dealing laser light may irradiate detection laser light as an operation in step S110. The space to which the detection laser light is irradiated may be overlayed to a space in which the laser oscillator <NUM>, that is irradiating dealing laser light, was irradiating detecting laser light. In addition, the space to which this detection laser light is irradiated may include the space in which the laser oscillator <NUM>, that is irradiating dealing laser light, was irradiating detection laser light.

The laser oscillator <NUM> changes a location to irradiate dealing laser light in accordance with a movement of the target <NUM>. The detector <NUM> obtains detection information while the laser oscillator <NUM> is irradiating dealing laser light. Since the target <NUM> reflects the dealing laser light as reflected light <NUM>, information of the target <NUM> is included in the detection information. The controller <NUM> estimates the position of the target <NUM> based on this detection information, similarly to step S130. Dealing signal with updated position of the target <NUM> is transmitted to the laser oscillator <NUM> that is already determined. The laser oscillator <NUM> irradiates dealing laser light to the updated position of the target <NUM>. The position of the target <NUM> may be estimated by irradiating detection laser light to the target <NUM> from a laser oscillator <NUM> that has not irradiated dealing laser light.

In step S150, the controller <NUM> determines whether the target <NUM> is destroyed. The controller <NUM> verifies whether the target <NUM> exists at the estimated position of the target <NUM>, based on detection information obtained by the detector <NUM>. For example, the controller <NUM> determines whether information of the target <NUM> is included in the detection information, similarly to step S120. When no information of the target <NUM> is included in the detection information, the controller <NUM> determines that the target <NUM> is destroyed. When information of the target <NUM> is included in the detection information, the position of the target <NUM> is estimated, similarly to step S130. When the location to which the laser oscillator <NUM> is irradiating dealing laser light, is not included in the estimated position of the target <NUM>, the controller <NUM> determines that the target <NUM> is destroyed. When the estimated position of the target <NUM> is same as the location to which the laser oscillator <NUM> is irradiating dealing laser light, the controller <NUM> determines that the target <NUM> is not destroyed. When the controller <NUM> determines that the target <NUM> is not destroyed, the process returns to step S140 and the laser oscillator <NUM> continues irradiating the dealing laser light to the target <NUM>. When the controller <NUM> determines that the target <NUM> is destroyed, the process returns to step S110 and the laser oscillator <NUM> irradiates detection laser light.

As described above, the laser irradiation apparatus <NUM> performs detection and destruction of target <NUM> by irradiating detection laser light and dealing laser light from laser oscillators <NUM>. Energy of the detection laser light may be smaller than energy of the dealing laser light.

As shown in <FIG>, the laser irradiation apparatus <NUM> may irradiate dealing laser light to a plurality of targets <NUM>. For example, information of a first target <NUM>-<NUM> and a second target <NUM>-<NUM> is included in the detection information that the detector <NUM> obtains. The controller <NUM> estimates a position of the first target <NUM>-<NUM> and a position of the second target <NUM>-<NUM>, based on the detection information. The controller <NUM> determines a laser oscillator <NUM> that irradiates dealing laser light to the first target <NUM>-<NUM> based on the estimated position of the first target <NUM>-<NUM> and determines a laser oscillator <NUM> that irradiates dealing laser light to the second target <NUM>-<NUM> based on the estimated position of the second target <NUM>-<NUM>. When a first laser oscillator <NUM>-<NUM> that can irradiate dealing laser light to the first target <NUM>-<NUM> is different from a second laser oscillator <NUM>-<NUM> that can irradiate dealing laser light to the second target <NUM>-<NUM>, the controller <NUM> transmits a dealing signal for irradiating dealing laser light to the targets <NUM> to each laser oscillator <NUM>. The laser oscillators <NUM> irradiate dealing laser light to the first target <NUM>-<NUM> or the second target <NUM>-<NUM>, based on the dealing signal.

When there is a laser oscillator <NUM> that can irradiate dealing laser light to both of the first target <NUM>-<NUM> and the second target <NUM>-<NUM>, the controller <NUM> determines a target <NUM> to assign to this laser oscillator <NUM>. For example, the controller <NUM> may assign a target <NUM> of which irradiation angle becomes smallest to the laser oscillator <NUM>. A target <NUM> may be assigned to the laser oscillator <NUM> so that a number of laser oscillators <NUM> that irradiates dealing laser light to the first target <NUM>-<NUM> becomes equal to a number of laser oscillators <NUM> that irradiates dealing laser light to the second target <NUM>-<NUM>.

The controller <NUM> may estimate target information such as a position, a speed, an acceleration and a traveling direction of the target <NUM> based on the detection information that the detector <NUM> has obtained, and may determine the target <NUM> to assign to the laser oscillator <NUM>. For example, the controller <NUM> may assign a target <NUM> of which a distance from the laser irradiation apparatus <NUM> is the shortest to the laser oscillator <NUM>. Based on a position and a speed of the target <NUM>, a target <NUM> that reaches the laser irradiation apparatus <NUM> the fastest may be assigned to the laser oscillator <NUM>. To estimate a speed or the like of the target <NUM>, at first, the controller <NUM> estimates a position of the target <NUM> at each time based on detection information that the detector <NUM> has obtained at different times. Next, the controller <NUM> estimates the speed or the like of the target <NUM> based on the times at which the detector <NUM> has obtained the detection information and a position of the target <NUM> at each time. When the laser irradiation apparatus <NUM> protects facilities or the like, the controller <NUM> may assign a target <NUM> of which a distance from the facilities to protect is the closest to the laser oscillator <NUM>. The target <NUM> that reaches the facilities to protect the fastest may be assigned to the laser oscillator <NUM>.

The target information may include types of moving objects such as aircraft, drone, flying object and vehicle. The controller <NUM> may estimate a type of the target <NUM> such as aircraft, drone, flying object and vehicle based on the detection information that the detector <NUM> has obtained and may determine the target <NUM> to assign to the laser oscillator <NUM>. In this case, the controller <NUM> estimates a shape of the target <NUM> based on the detection information that the detector <NUM> has obtained. The controller <NUM> searches for a registered shape that is the closest to the estimated shape in registered shapes that are registered. The type that corresponds to the registered shape that is searched is estimated as the type of the target <NUM>. A priority that corresponds to the estimated type is searched and a target <NUM> of which the priority is the highest is assigned to the laser oscillator <NUM>. In this case, registered shapes, types and priorities are registered in association in the controller <NUM>. In addition, a use, a model and the like of moving objects may be included in the target information. In this case, the priority is set to the use, the model and the like of the moving objects.

The controller <NUM> may calculate a threat level of the target <NUM> based on the detection information that the detector <NUM> has obtained and may assign a target <NUM> of which the threat level is the highest to the laser oscillator <NUM>. The threat level is calculated based on a type, a size, a speed, a traveling direction and the like of the target <NUM>.

The controller <NUM> may be provided with an input device and may assign a target <NUM> selected by a user to the laser oscillator <NUM>.

As shown in <FIG>, when the target <NUM> moves with a speed including a directional component parallel to an in-plane direction of the surface of the laser array <NUM>, the controller <NUM> may change a laser oscillator <NUM> that irradiates dealing laser light in accordance with the movement of the target <NUM>. For ease of understanding, it will be described by use of a cartesian coordinate system. It will be described with x direction and y direction as in-plane directions of the surface of the laser array <NUM> and z direction as normal direction of the surface of the laser array <NUM>.

For example, when the target <NUM> moves in +x direction, the controller <NUM> assigns the target <NUM> to the second laser oscillator <NUM>-<NUM> that is arranged in +x direction from the first laser oscillator <NUM>-<NUM> that is irradiating dealing laser light to the target <NUM>. The controller <NUM> stops the irradiation of the dealing laser light by the first laser oscillator <NUM>-<NUM>. When the target <NUM> further moves in +x direction, the controller <NUM> assigns the target <NUM> to the third laser oscillator <NUM>-<NUM> that is arranged in +x direction from the second laser oscillator <NUM>-<NUM> that is irradiating dealing laser light to the target <NUM>. The controller <NUM> stops the irradiation of the dealing laser light by the second laser oscillator <NUM>-<NUM>.

In particular, when the target <NUM> moves in +x direction, the laser oscillators <NUM> operate as following. As shown in <FIG>, irradiation oscillators 11a of the laser oscillators <NUM> are irradiating dealing laser light to the target <NUM>. Adjacent oscillators 11b of the laser oscillators <NUM>, that are arranged in an adjacent area <NUM> that is adjacent to the irradiation oscillators 11a, are not irradiating dealing laser light.

When the target <NUM> moves in +x direction, a part of the adjacent oscillators 11b irradiates dealing laser light to the target <NUM>. As the target <NUM> moves in +x direction, a first adjacent oscillator 11b-<NUM> arranged in +x direction from the irradiation oscillators 11a can irradiate dealing laser light to the target <NUM> with an angle with which the irradiation oscillators 11a were irradiating. As a result, the controller <NUM> generates dealing signal so that the first adjacent oscillator 11b-<NUM> irradiates dealing laser light to the target <NUM>. The first adjacent oscillator 11b-<NUM> irradiates dealing laser light to the target <NUM> based on the dealing signal.

When the target <NUM> moves in +x direction, a part of the irradiation oscillators 11a stops the irradiation of the dealing laser light. As the target <NUM> moves in +x direction, a first irradiation oscillator 11a-<NUM>, which is arranged in -x direction that is a direction opposite to the movement direction of the target <NUM>, cannot irradiate dealing laser light to the target <NUM> with the angle with which the irradiation oscillators 11a were irradiating. For this reason, the controller <NUM> generates dealing signal for the first irradiation oscillator 11a-<NUM> so as to stop the irradiation of the dealing laser light. The first irradiation oscillator <NUM>1a-<NUM> stops the irradiation of the dealing laser light based on the dealing signal.

The first adjacent oscillator 11b-<NUM> may irradiate dealing laser light before the first irradiation oscillator 11a-<NUM> stops the irradiation of the dealing laser light. In addition, the first adjacent oscillator 11b-<NUM> may irradiate dealing laser light after the first irradiation oscillator 11a-<NUM> stopped the irradiation of the dealing laser light. The first adjacent oscillator 11b-<NUM> may irradiate dealing laser light at a same time as the first irradiation oscillator <NUM>1a-<NUM> stops the irradiation of the dealing laser light.

The controller <NUM> may generate a dealing signal to transmit to the first adjacent oscillator 11b-<NUM> before generating a dealing signal to transmit to the first irradiation oscillator 11a-<NUM>. In addition, the controller <NUM> may generate a dealing signal to transmit to the first adjacent oscillator 11b-<NUM> after generating a dealing signal to transmit to the first irradiation oscillator 11a-<NUM>. The controller <NUM> may generate a dealing signal to transmit to the first adjacent oscillator 11b-<NUM> at a same time as generating a dealing signal to transmit to the first irradiation oscillator 11a-<NUM>.

An adjacent oscillator 11b arranged in the adjacent area <NUM> may be controlled so as not to irradiate detection laser light. It can be said that an adjacent oscillator 11b is a laser oscillator <NUM> with high probability of irradiating dealing laser light to the target <NUM>. An irradiation direction of detection laser light is controlled so that detection laser light is irradiated to entire detection space <NUM>. By controlling an adjacent oscillator 11b not to irradiate detection laser light, it is suppressed from starting irradiation of dealing laser light while irradiating detection laser light to the detection space <NUM>. A shape of the adjacent area <NUM> may be changed in accordance with a traveling direction, a speed, an acceleration or the like of the target <NUM>.

The controller <NUM> can control the laser oscillator <NUM> in a case in which the target <NUM> moves in y direction or the like, as in the case of movement in x direction.

As shown in <FIG>, the controller <NUM> may estimate an estimation path <NUM> of the target <NUM> based on the detection information and may determine a laser oscillator <NUM> that irradiates dealing laser light to the target <NUM> based on the estimation path <NUM>. Laser oscillators <NUM> that are irradiating dealing laser light to the target <NUM> are arranged in an irradiation area <NUM>. In this case, at first, the controller <NUM> estimates the estimation path <NUM> of the target <NUM>. For example, target information such as a position, a speed, an acceleration and a model of the target <NUM> is estimated based on the detection information that the detector <NUM> has obtained. The estimation path <NUM> of the target <NUM> is estimated based on the estimated target information of the target <NUM>.

Next, the controller <NUM> determines a laser oscillator <NUM> that irradiates dealing laser light to the target <NUM> at desired times, based on the estimation path <NUM>. For example, the controller <NUM> estimates estimation positions <NUM> of the target <NUM> at the desired times, such as a first estimation position <NUM>-<NUM> and a second estimation position <NUM>-<NUM>, based on the estimation path <NUM> of the target <NUM>. A laser oscillator <NUM> that irradiates dealing laser light when the target <NUM> reaches the first estimation position <NUM>-<NUM> (for example, a laser oscillator <NUM> arranged in a first estimation irradiation area <NUM>-<NUM>) is determined based on the first estimation position <NUM>-<NUM>. Similarly, a laser oscillator <NUM> that irradiates dealing laser light when the target <NUM> reaches the second estimation position <NUM>-<NUM> (for example, a laser oscillator <NUM> arranged in a second estimation irradiation area <NUM>-<NUM>) is determined based on the second estimation position <NUM>-<NUM>.

The controller <NUM> determines a schedule for the laser oscillator <NUM> to irradiate dealing laser light to the target <NUM> and controls the laser oscillator <NUM> based on the schedule. The controller <NUM> determines a schedule for each laser oscillator <NUM> to irradiate dealing laser light, based on times when the target <NUM> reaches the estimation positions <NUM> and the laser oscillators <NUM> arranged in the estimation irradiation areas <NUM>. The controller <NUM> generates dealing signal to control the laser oscillators <NUM>, according to this schedule. For example, the dealing signal is transmitted to the laser oscillators <NUM> arranged in the first estimation irradiation area <NUM>-<NUM> at a time when the target <NUM> reaches the first estimation position <NUM>-<NUM>. As a result, the laser oscillators <NUM> irradiate dealing laser light to the target <NUM> in accordance with the determined schedule.

As described above, the controller <NUM> may determine the schedule for the laser oscillators <NUM> to irradiate dealing laser light to the target <NUM> by estimating the estimation path <NUM> of the target <NUM>. This schedule may be updated when the detector <NUM> obtains the detection information. As shown in <FIG>, when a plurality of targets <NUM> are detected, a laser oscillator <NUM> that irradiates dealing laser light to each target <NUM> may be determined.

The invention is shown in <FIG>. The controller <NUM> selects laser oscillators <NUM> that irradiate detection laser light so that an image such as letters or diagram is displayed on the laser array <NUM>. For example, the controller <NUM> determines an area in accordance with the shape of the letters "AAA" in the laser array <NUM> (for example, an area occupied by the letters, an area occupied by edges of the letters or the like). The controller <NUM> selects the laser oscillators <NUM> arranged in this area as a laser oscillator group and transmits detection signal that instructs the selected laser oscillator group to irradiate detection laser light. The laser oscillators <NUM> included in the laser oscillator group irradiate output laser light <NUM> as detection laser light, based on the detection signal. For this reason, a laser light group including output laser light <NUM> irradiated by each laser oscillator <NUM> is irradiated. When viewing the laser array <NUM> from a direction in which this laser light group is irradiated, the letters "AAA" are displayed. In addition, as the laser oscillators <NUM> irradiate detection laser light, the detection laser light is reflected by the target <NUM> and reaches the detector <NUM>. As a result, the detector <NUM> can detect the target <NUM>. As described above, the laser array <NUM> can detect the target <NUM> by displaying letters.

A direction of irradiating detection laser light can be arbitrarily selected in accordance with a direction of displaying an image on the laser array <NUM>. For example, when displaying an image to a plurality of directions, corresponding laser oscillators <NUM> irradiate detection laser light to the plurality of directions. For example, by setting an interval of irradiating detection laser light to a predetermined direction to <NUM>/<NUM> second, an image on the laser array <NUM> is displayed when viewing the laser array <NUM> from this direction. When a part of laser oscillators <NUM> selected in accordance with the image is irradiating detection laser light to a first direction, other laser oscillators <NUM> thereof may irradiate detection laser light to a direction different from the first direction.

As shown in <FIG>, the controller <NUM> may change the image displayed on the laser array <NUM> in accordance with a direction of viewing the laser array <NUM>.

For example, the controller <NUM> controls the laser oscillators <NUM> so as to irradiate the laser light group, in accordance with the shape of a string of letters "AAA", in the first direction. In particular, the controller <NUM> determines an area on the laser array <NUM> in accordance with the shape of the string of letters "AAA" and selects the laser oscillators <NUM> arranged in this area as the first laser oscillator group. The selected first laser oscillator group irradiates a first output laser light <NUM>-<NUM> as detection laser light in the first direction, in accordance with the instruction from the controller <NUM>. As a result, the string of letters "AAA" is displayed when viewing the laser array <NUM> from the first direction.

Similarly, the controller <NUM> controls the laser oscillators <NUM> so as to irradiate a laser light group in accordance with a shape of a string of letters "BBB" in a second direction different from the first direction. In particular, the controller <NUM> determines an area on the laser array <NUM> in accordance with a shape of the string of letters "BBB" and selects the laser oscillators <NUM> arranged in this area as a second laser oscillator group. The selected second laser oscillator group irradiates a second output laser light <NUM>-<NUM> as detection laser light in the second direction, in accordance with the instruction from the controller <NUM>. As a result, the string of letters "BBB" is displayed when viewing the laser array <NUM> from the second direction.

A laser oscillator <NUM> included in both of the first laser oscillator group and the second laser oscillator group irradiates detection laser light in the first direction and the second direction. As a result, different images can be displayed in a plurality of directions with a single laser array <NUM>.

The controller <NUM> may control the laser oscillators <NUM> by software processing. In this case, the controller <NUM> is provided with a processor <NUM> and a storage device <NUM>, as shown in <FIG>.

The storage device <NUM> stores various data used to control the laser oscillators <NUM>. For example, laser irradiation software <NUM> is installed in the storage device <NUM> and the storage device <NUM> is used as a non-transitory tangible storage medium that stores the laser irradiation software <NUM>. The laser irradiation software <NUM> may be provided as a computer program product recorded in a computer readable recording medium <NUM> or may be provided as a computer program product that is downloadable from a server.

The processor <NUM> executes the laser irradiation software <NUM> and performs various data processes to control the laser oscillators <NUM>. The processor <NUM> generates detection signal and dealing signal to control the laser oscillators <NUM> and estimates a position of the target <NUM>. For example, the laser oscillators <NUM> irradiate detection laser light based on the detection signal. The processor <NUM> estimates a position of the target <NUM> based on reflected light <NUM> of the detection laser light that the detector <NUM> has detected. The processor <NUM> generates dealing signal based on the estimated position. The laser oscillator <NUM> irradiates dealing laser light to the target <NUM> based on the dealing signal.

A laser oscillator <NUM> that can non-mechanically change irradiation direction of the output laser light <NUM> will be described. The laser oscillator <NUM> is provided with, for example, an optical device <NUM> and a laser device <NUM>, as shown in <FIG>.

The laser device <NUM> is provided around the optical device <NUM> and is configured to irradiate seed light <NUM> to an input surface <NUM> of the optical device <NUM> from a plurality of directions. The optical device <NUM> is configured to irradiate the seed light <NUM>, that is irradiated to the input surface <NUM>, as the output laser light <NUM> from an output surface <NUM>. A direction in which the output laser light <NUM> is irradiated is determined based on wavelength and irradiation direction of the seed light <NUM> that the laser device <NUM> irradiates to the optical device <NUM>. The wavelength and the irradiation direction of the seed light <NUM> are configured so as to be controlled by the controller <NUM>.

The seed light <NUM> is a generic term of first seed light <NUM>-<NUM> (not illustrated), second seed light <NUM>-<NUM> (not illustrated),. , and N-th seed light <NUM>-N (not illustrated) of which irradiation directions are different. The output laser light <NUM> is a generic term of first output laser light <NUM>-<NUM> (not illustrated), second output laser light <NUM>-<NUM> (not illustrated),. , and N-th output laser light <NUM>-N that are irradiated when each of the seed light <NUM> is irradiated to the optical device <NUM>. When the first seed light <NUM>-<NUM> is irradiated to the optical device <NUM>, the optical device <NUM> irradiates the first output laser light <NUM>-<NUM>. When the second seed light <NUM>-<NUM> is irradiated to the optical device <NUM>, the optical device <NUM> irradiates the second output laser light <NUM>-<NUM>. When the N-th seed light <NUM>-N is irradiated to the optical device <NUM>, the optical device <NUM> irradiates the N-th output laser light <NUM>-N.

As shown in <FIG> and <FIG>, the optical device <NUM> is formed in a cylindric shape, for example, and has an input surface <NUM> and an output surface <NUM> in one bottom surface. The input surface <NUM> is a plane surface provided at an edge portion of this bottom surface for example, and is configured so as to be irradiated by the laser device <NUM> with the seed light <NUM>. The output surface <NUM> is a plane surface provided to this bottom surface and is configured to irradiate the output laser light <NUM>. The output surface <NUM> may be formed in a circular shape in a center of this bottom surface, for example.

The optical device <NUM> is formed with a second reflection mirror <NUM>, an active layer <NUM>, a first reflection mirror <NUM> and a first electrode <NUM> that are laminated on one surface of a substrate <NUM> in order. Boundaries between each layer are provided in parallel to a bottom surface of the optical device <NUM> for example, the output surface <NUM> for example. In addition, a second electrode <NUM> is provided adjacent to another surface of the substrate <NUM>.

The first reflection mirror <NUM> has an input surface <NUM> at an end portion of a surface thereof, for example. The seed light <NUM> irradiated from the laser device <NUM> is incident from the input surface <NUM> to the first reflection mirror <NUM>. For this reason, the input surface <NUM> is configured so that a reflectance thereof is lower compared to another portion of the surface of the first reflection mirror <NUM>. For example, the first reflection mirror <NUM> is formed so that a thickness of the first reflection mirror <NUM> at a position where the input surface <NUM> is provided is thinner than a thickness of the first reflection mirror <NUM> at another position. The input surface <NUM> is, for example, a plane surface parallel to the output surface <NUM>.

Laser light incident from the input surface <NUM> travels inside the optical device <NUM> as propagation laser light <NUM>. The propagation laser light <NUM> is a generic term of first propagation laser light <NUM>-<NUM>, second propagation laser light <NUM>-<NUM>,. , and N-th propagation laser light <NUM>-N which propagate in the optical device <NUM> when each of the seed light <NUM> is irradiated. In particular, when the first seed light <NUM>-<NUM> is irradiated to the optical device <NUM>, it travels in the optical device <NUM> as the first propagation laser light <NUM>-<NUM>. When the second seed light <NUM>-<NUM> is irradiated to the optical device <NUM>, it travels in the optical device <NUM> as the second propagation laser light <NUM>-<NUM>. When the N-th seed light <NUM>-N is irradiated to the optical device <NUM>, it travels in the optical device <NUM> as the N-th propagation laser light <NUM>-N.

The first reflection mirror <NUM> and the second reflection mirror <NUM> are provided to face to each other and form a planar waveguide <NUM> between the first reflection mirror <NUM> and the second reflection mirror <NUM>. In particular, the second reflection mirror <NUM> reflects the propagation laser light <NUM> incident from the input surface <NUM>. A portion of the propagation laser light <NUM> reflected by the second reflection mirror <NUM> is reflected to the first reflection mirror <NUM>. The propagation laser light <NUM> reflected by the first reflection mirror <NUM> is reflected by the second reflection mirror <NUM>. As described above, the propagation laser light <NUM> is reflected by the first reflection mirror <NUM> and the second reflection mirror <NUM> in order to travel in the planar waveguide <NUM>. The first reflection mirror <NUM> and the second reflection mirror <NUM> are formed so as to carry out Bragg reflection and include a Distributed Bragg Reflector for example.

The first reflection mirror <NUM> transmits a portion of the propagation laser light <NUM> and reflects another portion thereof. The propagation laser light <NUM> reflected by the first reflection mirror <NUM> travels inside the optical device <NUM>. The propagation laser light <NUM> transmitted through the first reflection mirror <NUM> is irradiated from the output surface <NUM> formed on the surface of the first reflection mirror <NUM> as the output laser light <NUM>.

On the other hand, the second reflection mirror <NUM> may reflect the whole propagation laser light <NUM>. For this reason, the reflectance of the first reflection mirror <NUM> may be configured to be lower than the reflectance of the second reflection mirror <NUM>. For example, the thickness of the first reflection mirror <NUM> may be thinner than the thickness of the second reflection mirror <NUM>.

The active layer <NUM> is provided between the first reflection mirror <NUM> and the second reflection mirror <NUM> and amplifies the propagation laser light <NUM> passing through the active layer <NUM>. When the propagation laser light <NUM> travels in the planar waveguide <NUM>, a portion of the propagation laser light <NUM> is irradiated as the output laser light <NUM> and another portion of the propagation laser light <NUM> is amplified by the active layer <NUM>.

The active layer <NUM> is excited by a current that flows between the first electrode <NUM> and the second electrode <NUM>. For example, the active layer <NUM> may be excited until it becomes a luminescent state. The first electrode <NUM> and the second electrode <NUM> are provided to sandwich the active layer <NUM>.

The first electrode <NUM> and the second electrode <NUM> are connected to the controller <NUM>. The controller <NUM> draws a current between the first electrode <NUM> and the second electrode <NUM> and excites the active layer <NUM>. The controller <NUM> adjusts the amplification of the propagation laser light <NUM> by the active layer <NUM>, by controlling the current which flows in the active layer <NUM>.

As shown in <FIG>, the first electrode <NUM> is formed so as not to overlap the input surface <NUM> irradiated with the seed light <NUM> and the output surface <NUM> irradiated with the output laser light <NUM>. The input surface <NUM> is provided at an edge portion of the optical device <NUM> in a direction in which the seed light <NUM> is irradiated. The output surface <NUM> is formed, for example, in a circular shape in a center of the bottom surface of the optical device <NUM>.

As described above, the optical device <NUM> propagates the propagation laser light <NUM> along the planar waveguide <NUM> provided between the first reflection mirror <NUM> and the second reflection mirror <NUM>, and irradiates the output laser light <NUM> from the output surface <NUM>. The optical device <NUM> includes a Vertical Cavity Surface Emitting LASER (VCSEL) for example. For example, a diameter of the output surface <NUM> of the optical device <NUM> may be <NUM>.

The laser device <NUM> is provided with a plurality of seed light sources <NUM> (a first seed light source <NUM>-<NUM>, a second seed light source <NUM>-<NUM>,. , a N-th seed light source <NUM>-N), for example.

The seed light sources <NUM> irradiate the seed light <NUM> to the optical device <NUM>. For example, each of the seed light sources <NUM>, with different direction of irradiating the seed light <NUM>, irradiates the first seed light <NUM>-<NUM>, the second seed light <NUM>-<NUM>,. , and the N-th seed light <NUM>-N. In particular, the first seed light source <NUM>-<NUM> irradiates the first seed light <NUM>-<NUM> to the optical device <NUM>. The second seed light source <NUM>-<NUM> irradiates the second seed light <NUM>-<NUM> to the optical device <NUM>. The N-th seed light source <NUM>-N irradiates the N-th seed light <NUM>-N to the optical device <NUM>. A portion of the seed light sources <NUM>, the first seed light source <NUM>-<NUM> and the second seed light source <NUM>-<NUM> for example, may irradiate the seed light <NUM> in a same direction. In addition, the seed light source <NUM> may be connected to a device that outputs the seed light <NUM> via an optical switch and may be configured to irradiate the seed light <NUM> outputted by this device. In this case, the optical switch selects a seed light source <NUM> that irradiates the seed light <NUM>. An example of the seed light source <NUM> includes a collimator, a fiber array that bundles optical fibers, and the like.

The seed light sources <NUM> are arranged to surround the optical device <NUM>. The seed light sources <NUM> are arranged to surround a half of the optical device <NUM> when viewed from a normal direction of the output surface <NUM> for example, and each of the seed light sources <NUM> is arranged at equal intervals.

For ease of understanding, it will be described by use of a spherical coordinate system with a center of the output surface <NUM> as its origin. A distance from the origin will be referred to as a radius r, an angle from a normal line <NUM> of the output surface <NUM> will be referred to as a polar angle θ and a direction in a planar direction of the output surface <NUM> when viewed from the origin will be referred to as an azimuthal φ.

A method of controlling the azimuthal φ of the irradiation direction of the output laser light <NUM> will be described. The laser device <NUM> irradiates the seed light <NUM> to the optical device <NUM> from an i-th seed light source <NUM>-i and a k-th seed light source <NUM>-k, for example. Azimuthal φ of the irradiation direction of the seed light <NUM> that the i-th seed light source <NUM>-i and the k-th seed light source <NUM>-k irradiate is not parallel to each other. As the input surface <NUM> is a plane surface, the azimuthal φ of the traveling direction of the i-th propagation laser light <NUM>-i corresponding to the i-th seed light <NUM>-i and the azimuthal φ of the traveling direction of the k-th propagation laser light <NUM>-k corresponding to the k-th seed light <NUM>-k are not parallel to each other. As the output surface <NUM> is a plane surface, the azimuthal φ of the irradiation direction of the i-th output laser light <NUM>-i corresponding to the i-th propagation laser light <NUM>-i and the azimuthal φ of the irradiation direction of the k-th output laser light <NUM>-k corresponding to the k-th propagation laser light <NUM>-k are not parallel to each other. As described above, the azimuthal φ of the irradiation direction of the output laser light <NUM> when the seed light <NUM> is irradiated from the i-th seed light source <NUM>-i and the azimuthal φ of the irradiation direction of the output laser light <NUM> when the seed light <NUM> is irradiated from the k-th seed light source <NUM>-k are different. The azimuthal φ of the irradiation direction of the output laser light <NUM> can be changed by changing the seed light source <NUM> that is to irradiate the seed light <NUM>.

As described above, the laser oscillators <NUM> can control the azimuthal φ of the irradiation direction of the output laser light <NUM> by changing the seed light source <NUM> that irradiates the seed light <NUM>. In other words, the azimuthal φ of the irradiation direction of the output laser light <NUM> can be controlled by irradiation by the laser device <NUM> of a plurality of beams of seed light <NUM> of which the azimuthal φ of the traveling direction is not parallel to each other in the planar waveguide <NUM>. A plurality of optical paths of the propagation laser light <NUM>, that is irradiated from a plurality of seed light sources <NUM> and travels inside the optical device <NUM>, may cross each other inside the planar waveguide <NUM> formed in the optical device <NUM>, when viewed from the normal direction of the output surface. For example, an optical path of the i-th propagation laser light <NUM>-i and an optical path of the k-th propagation laser light <NUM>-k may cross inside the planar waveguide <NUM> when viewed from the normal direction of the output surface. It should be noted that two seed light sources <NUM> of the plurality of seed light sources <NUM> may irradiate seed light <NUM> to the optical device <NUM> from parallel directions.

The polar angle θ of the irradiation direction of the output laser light <NUM> can be changed by changing a wavelength of the seed light <NUM> irradiated from the seed light source <NUM>. As shown in <FIG>, the seed light <NUM> is irradiated to the input surface <NUM> from a direction inclined with respect to the normal direction of the input surface <NUM> and is guided inside the optical device <NUM> as the propagation laser light <NUM>. The propagation laser light <NUM> is reflected by the first reflection mirror <NUM> and the second reflection mirror <NUM>. When an incident angle <NUM> of the propagation laser light <NUM> at the first reflection mirror <NUM> is referred to as θi, the following equation (<NUM>) holds based on Bragg's law. [Math Equation <NUM>] <MAT> Herein, the incident angle <NUM> indicates an angle between an incident direction of the propagation laser light <NUM> with respect to the first reflection mirror <NUM> and the normal line <NUM> of the output surface <NUM>. In addition, λ indicates a wavelength of the propagation laser light <NUM> and λc indicates a cut-off wavelength of the planar waveguide <NUM>.

The first reflection mirror <NUM> transmits a portion of the propagation laser light <NUM>, which is incident with an incident angle <NUM>, as the output laser light <NUM>. The output laser light <NUM> is refracted at the output surface <NUM>, which is provided to the first reflection mirror <NUM>, and is irradiated. As the wavelength of the output laser light <NUM> is equal to the wavelength of the propagation laser light <NUM>, when an output angle <NUM> which indicates an angle between a direction in which the output laser light <NUM> is irradiated and the normal line <NUM> of the output surface <NUM> is referred to as θ<NUM>, the following equation (<NUM>) holds. [Math Equation <NUM>] <MAT> Herein, nair indicates a refraction index of the atmosphere and nwg indicates a refraction index of the planar waveguide <NUM>.

As the wavelength of the propagation laser light <NUM> and the wavelength of the output laser light <NUM> are equal to the seed light <NUM>, the output angle <NUM> varies based on the wavelength of the seed light <NUM>. As the output angle <NUM> indicates a polar angle θ of the direction in which the output laser light <NUM> is irradiated, the polar angle θ of the direction in which the output laser light <NUM> is irradiated is changed based on the wavelength of the seed light <NUM>. As a result, the laser oscillator <NUM> can control the polar angle θ of the irradiation direction of the output laser light <NUM> by changing the wavelength of the seed light <NUM>.

As described above, the laser oscillator <NUM> can change non-mechanically and two-dimensionally the direction of the output laser light <NUM> to irradiate by controlling the seed light source <NUM> that irradiates the seed light <NUM> and the wavelength of the laser light that the seed light source <NUM> irradiates. For example, the laser oscillator <NUM> can change a polar angle and an azimuthal of the direction to irradiate laser light in a spherical coordinate system with a position of outputting the laser light as an origin and a direction of irradiating the laser light as a zenith.

When the laser irradiation apparatus <NUM> is provided with the laser oscillator <NUM> shown in <FIG> and <FIG>, the controller <NUM> can control the irradiation direction of the output laser light <NUM> by selecting the wavelength of the seed light <NUM> and the seed light source <NUM>. Output energy of the output laser light <NUM> is adjusted by a control of the controller <NUM> on a current which flows between the first electrode <NUM> and the second electrode <NUM>, and output energy of the seed light <NUM>.

A direction in which each of the laser oscillators <NUM> can irradiate output laser light <NUM> may not be identic. For example, directions in which adjacent laser oscillators <NUM> can irradiate output laser light <NUM> may be different. As directions in which adjacent laser oscillators <NUM> can irradiate output laser light <NUM> are different, irradiation directions can be completed. As a result, directions in which the laser array <NUM> can irradiate output laser light <NUM> can be widened.

Claim 1:
A laser irradiation apparatus comprising:
a laser array comprising a plurality of laser oscillators (<NUM>) including a first laser oscillator configured to irradiate first detection laser light (<NUM>);
a detector (<NUM>) configured to obtain detection information based on reflected light that is the first detection laser light (<NUM>) reflected by a target (<NUM>); and
a controller (<NUM>) configured to estimates a position of the target (<NUM>) based on the detection information,
wherein the plurality of laser oscillators (<NUM>) includes a first laser oscillator group,
characterized in that
the first laser oscillator group is configured to irradiate a first laser light group (<NUM>-<NUM>) in a first direction to display a first image when viewing the laser array from the first direction, and
wherein the first laser oscillator is included in the first laser oscillator group and the first detection laser light is included in the first laser light group (<NUM>-<NUM>),
wherein the plurality of laser oscillators includes a second laser oscillator group configured to irradiate a second laser light group (<NUM>-<NUM>) in a second direction to display a second image when viewing the laser array from the second direction.