Method and computing unit for controlling at least one drive unit or at least one deflection unit of a microscanner device

Abstract

Method for controlling at least one drive unit (30, 55, 56) and at least one deflection unit (25, 60, 61), in particular a micromirror, a two-dimensional microscanner device (40), the method comprising the following process steps: - Generating (100) first control signals (11, 420a, 420b) for controlling the drive unit (30, 55, 56) of the at least one deflection unit (25, 60, 61) by means of at least one computing unit (10, 65), and - Generating (110) second control signals (12) for controlling the drive unit (30, 55, 56) of the at least one deflection unit (25, 60, 61) by means of the at least one computing unit (10, 65), and - Transmitting (120) the first control signals (11, 420a, 420b) from the at least one computing unit (10, 65) to the at least one drive unit (30, 55, 56), and - Transmitting (130) the second control signals (12) from the at least one computing unit (10, 65, 76) to the at least one drive unit (25, 60, 61), and - Execution (130) of a sinusoidal first motion (320a), in particular a first rotational motion, of which at least one deflection unit (25, 60, 61) about a first axis (62), in particular a horizontal axis, depending on the transmitted first control signals (11, 420a, 420b) at a first time (301), and - Execution (140) of a sinusoidal second motion (340), in particular a second rotational motion, which includes at least one deflection unit (25, 60, 61) about a second axis (57) arranged substantially perpendicular to the first axis (62), in particular about a vertical axis, at the first time (301), wherein the first control signals (11, 420a, 420b) transmitted from the at least one computing unit (10, 65) to the at least one drive unit (25, 60, 61) are adapted (219) such that a periodic third movement (330) is superimposed on the first movement (320a) at a second time (305) following the first time (301), or wherein the second control signals (12) transmitted from the at least one computing unit (10, 65) to the at least one drive unit (25, 60, 61) are adapted (220) such that a periodic fourth movement is superimposed on the second movement (340) at the second time (305) following the first time (301), characterized by the fact that the sinusoidal first motion (320a) of the at least one deflection unit (25, 60, 61) about the first axis (62) is performed with a defined first frequency f1 (160), and the sinusoidal second motion of the at least one deflection unit (25, 60, 61) about the second axis (57) is performed with a defined second frequency f2 (170), wherein, depending on the frequencies f1 and f2, image points in the form of a Lissajous figure (455a, 455b, 456a, 456b, 510) are projected onto a provided, in particular rectangular, projection volume (500) by means of the deflection unit (25, 60, 61) (180).

Description

State of the art

[0001] The invention relates to a method and a computing unit for controlling at least one drive unit and at least one deflection unit of a microscanner device. The invention further relates to a microscanner device comprising the computing unit according to the invention.

[0002] Document EP 1 508 242 B1 describes the deflection of a light beam to project an image onto a screen. The light beam oscillates, in particular, in a sinusoidal pattern in the horizontal and vertical directions, sweeping across the screen in the form of a Lissajous figure. The document describes how the trajectory sweeps across the screen uniformly or unevenly through targeted phase shifts in the horizontal and vertical directions. The manipulation of frequencies—especially in the vertical direction—is intended to counteract image aberrations. Furthermore, image quality is improved by modulating the intensity of the light beam depending on the area it sweeps across.

[0003] Further methods for controlling a drive unit of a deflection unit of a two-dimensional microscanner device, which have at least parts of claim 1, are described in documents EP 2 960 708 A1 and DE 10 2004 063 554 A1.

[0004] The invention is based on the objective of developing a method and a computing unit for controlling at least one drive unit and at least one deflection unit of a microscanner device, in which the trajectory sweeps over the image area more evenly and with a higher average resolution. Disclosure of the invention

[0005] To solve the problem, a method for controlling at least one drive unit, at least one deflection unit, in particular a micromirror, of a two-dimensional microscanner device according to claim 1 is proposed. First, control signals for controlling the drive unit of the at least one deflection unit are generated by means of at least one processing unit. Second control signals for controlling the drive unit of the at least one deflection unit are then generated by means of the processing unit. The first and / or second control signals can, for example, be electrical and / or pneumatic control signals. The first and / or second control signals can also have a sinusoidal waveform. Alternatively, the first and / or second control signals can, for example, have a rectangular waveform.The first and second control signals are subsequently transmitted from the processing unit to the at least one drive unit. Depending on the transmitted first control signals, a sinusoidal first movement of the at least one deflection unit about a first axis is then performed at a first time. This sinusoidal first movement about the first axis is, in particular, a rotational movement of the at least one deflection unit about a horizontal axis. The at least one deflection unit is thus rotated about the first axis such that the trajectory of a light beam deflected by the deflection unit is in a vertical direction. Furthermore, at the first time, depending on the transmitted second control signals, a sinusoidal second movement of the at least one deflection unit about a second axis arranged substantially perpendicular to the first axis is performed.The sinusoidal second movement about the first axis is, in particular, a rotational movement of the at least one deflection unit about a vertical axis. The at least one deflection unit is thus rotated about the second axis in such a way that the trajectory of a light beam deflected by the deflection unit runs in a horizontal direction.

[0006] The first control signals transmitted by the processing unit to the at least one drive unit are adjusted such that a periodic third movement is superimposed on the first movement at a second time point following the first. Alternatively, the second control signals transmitted by the processing unit to the at least one drive unit are adjusted such that a periodic fourth movement is superimposed on the second movement at a second time point following the first. For this purpose, the zero crossing of the first and / or second control signals can be modified, for example. The periodic third movement superimposed on the first movement and / or the periodic fourth movement superimposed on the second movement can, for example, be designed as a rectangular motion pattern.The described method results in significantly better homogeneity of the scanning without clearly recognizable areas of low resolution.

[0007] Preferably, the sinusoidal first movement of the at least one deflection unit around the first axis is performed resonantly, depending on the transmitted first control signals. The first control signals are then adjusted such that a controlled third movement, as a periodic third movement, is superimposed on this resonant first movement at the second time point following the first. Thus, the sinusoidal first movement has a significantly higher frequency than the frequency of the superimposed third movement. This results in the first movement determining the actual path of the movement around the first axis at the second time point, and the third superimposed movement merely shifts the first movement. Movements with a comparatively small amplitude require less power and can be generated more quickly.Preferably, the sinusoidal first movement of the at least one deflection unit around the first axis has a period T1, depending on the transmitted first control signals. The first control signals are adjusted in this context such that the periodic third movement generated at the second time point following the first has a period T3. The ratio of T1 to T3 is at most 1:50, preferably 1:10.

[0008] Preferably, the first control signals are adjusted such that a periodic rectangular third movement is superimposed on the first movement. Alternatively, the second control signals are adjusted such that a periodic rectangular fourth movement is superimposed on the second movement. This simply shifts the zero crossing of the first or second movement up or down, thus shifting the entire projected image at the second time point. Alternatively, the first control signals are adjusted such that a triangular, sawtooth, or further sinusoidal movement is superimposed on the first movement as a periodic third movement.Similarly, the second control signals are adjusted such that a triangular, sawtooth, or further sinusoidal movement is superimposed on the second movement as a periodic fourth movement. The superimposed periodic third movement preferably has a constant third amplitude. Alternatively, the superimposed periodic fourth movement preferably has a constant fourth amplitude. Thus, a uniform displacement of the projected image can always be achieved, resulting in a consistently high resolution of the projected image. Alternatively, the superimposed periodic third movement has a third amplitude that is not constant from one oscillation to the next. Similarly, the superimposed periodic fourth movement can also have a fourth amplitude that is not constant from one oscillation to the next.Thus, the projected image is shifted unevenly from one oscillation cycle to the next, resulting in even better homogeneity of the projected image.

[0009] According to the invention, the at least one deflection unit performs a sinusoidal first movement about the first axis with a defined first frequency f1, and the at least one deflection unit performs a sinusoidal second movement about the second axis with a defined second frequency f2. Depending on the frequencies f1 and f2, image points in the form of a Lissajous figure are then projected onto a designated, in particular rectangular, projection volume by means of the deflection unit. In the case of an integer ratio of the frequencies f1 and f2, the trajectory moves once upwards and then downwards again, in order to then close and write the image. Such an upward and downward movement of the trajectory is referred to as one pass of the Lissajous figure. In the case of a non-integer ratio of the frequencies, several passes are required until the Lissajous figure closes.With a non-integer ratio, for example 10.2 (f1 being 3000 Hz and f2 30600 Hz), the trajectory goes down and up again repeatedly until the number of these movements, multiplied by the frequency ratio, results in an integer value. With a ratio of 10.2:1, this would result in 5 iterations until the Lissajous figure is complete. The 5 iterations are projected such that a different line is written for each iteration. In this context, the period of the superimposed third or fourth periodic motion preferably corresponds to the time required for one iteration of the Lissajous figure. Alternatively, the time required for one iteration of the Lissajous figure can also correspond to the multiple of a period of the superimposed third or fourth periodic motion.Preferably, the superimposed periodic third or fourth motion is modeled on the uniform motion of the Lissajous figure and corresponds to a linear ramp rising and falling. In this context, the linear ramp preferably rises during the first iteration of the Lissajous figure and falls again during the next iteration. Preferably, the second time point following the first is determined by the time course of the sinusoidal first and / or second motion of the at least one deflection unit. The second time point is thus determined based on the recorded time-dependent course of the first and / or second motion. Preferably, the second time point is reached after half a period of the sinusoidal first and / or second motion.Preferably, the second time point is determined based on a detected rotation angle α1 of the at least one deflection unit about the first axis and a detected rotation angle α2 of the at least one deflection unit about the second axis. Preferably, however, the second time point occurs directly at the beginning of the process and thus simultaneously with the first time point. This allows the adjustment of the first or second control signals to also occur directly at the beginning of the process. The rotation angle is preferably detected continuously, for example, using sensors such as a camera or a capacitive sensor. To determine the temporal progression of the first and / or second movement using only a clock, for example, only the rotation angle α1 of the at least one deflection unit about the first axis and / or the rotation angle α2 of the at least one deflection unit detected at the first time point is required.If the initial rotation angles α1 and α2, as well as the frequencies f1 and f2, are known, the processing unit can determine the subsequent temporal progression of the first and / or second movement using only a clock. Preferably, the second point in time is reached after half a period of the sinusoidal first and / or second movement.

[0010] A further aspect of the present invention is a computing unit for controlling at least one drive unit, at least one deflection unit, in particular a micromirror, of a two-dimensional microscanner device. In this context, the computing unit is configured to transmit first control signals to the at least one drive unit at a first time for generating a sinusoidal first movement, in particular a first rotational movement, of the at least one deflection unit about a first axis, in particular about a horizontal axis. Additionally, the computing unit serves to transmit second control signals to the at least one drive unit at a first time for generating a sinusoidal second movement, in particular a second rotational movement, of the at least one deflection unit about a second axis, in particular about a vertical axis.The first and second axes are essentially perpendicular to each other. The processing unit is additionally configured to adjust the first control signals such that a periodic third movement is superimposed on the first movement at a second time point following the first. Alternatively, the processing unit is configured to adjust the second control signals such that a periodic fourth movement is superimposed on the second movement at a second time point following the first.

[0011] Furthermore, the computing unit is preferably configured to transmit the first control signals to at least one drive unit in such a way that the sinusoidal first movement of the at least one deflection unit about the first axis is carried out resonantly. In this context, the computing unit is further configured to adapt the first control signals in such a way that a controlled third movement is superimposed on the first movement as a periodic third movement at the second time point following the first time point.

[0012] Preferably, the computing unit is configured to generate the first control signals and transmit them to at least one drive unit such that the sinusoidal first movement has a defined period T1. The computing unit is further configured to adapt the first control signals such that the periodic third movement generated at the second time point following the first has a defined period T3, wherein the ratio of T1 to T3 is at most 1:50, in particular 1:10.

[0013] Preferably, the processing unit is configured to adjust the first control signals such that a periodic rectangular third movement is superimposed on the first movement at the second time point following the first. Alternatively, the processing unit serves to adjust the second control signals such that a periodic rectangular fourth movement, in particular with a constant fourth amplitude, is superimposed on the second movement at the second time point following the first.

[0014] According to the invention, the processing unit is configured to generate the first control signals such that the sinusoidal first movement of the at least one deflection unit about the first axis is carried out at a defined first frequency f1. In this context, the processing unit is further configured to generate the second control signals such that the sinusoidal second movement of the at least one deflection unit about the second axis is carried out at a defined second frequency f2. Depending on the frequencies f1 and f2, pixels in the form of a Lissajous figure are projected onto a provided, in particular rectangular, projection unit by means of the at least one deflection unit. The processing unit is configured to determine the second time point following the first time point as a function of the time course of the sinusoidal first and / or second movement of the at least one deflection unit.The computing unit is therefore aware of the time-dependent course of the first and / or second movement, and depending on this course, the computing unit also knows when the first or second control signals must be adjusted so that at the second time point following the first time point, the third or fourth movement is superimposed on the first or second movement.

[0015] A further object of the present invention is a microscanner device comprising the previously described computing unit for controlling at least one drive unit and at least one deflection unit, in particular a micromirror, of the microscanner device. The microscanner device is, in particular, a two-dimensional microscanner device, which is thus configured to project the deflected light beam two-dimensionally onto the projection volume. For this purpose, the microscanner device preferably comprises a first deflection unit, in particular a first micromirror, with an associated first drive unit, and a second deflection unit, in particular a second micromirror, with an associated second drive unit. The first drive unit can, for example, be configured as a piezoelectric drive and the second drive unit as an electromagnetic drive.Depending on the transmitted first control signals, the first deflection unit is configured to perform a sinusoidal first movement, in particular a first rotational movement, about a first axis, especially a horizontal axis. Depending on the transmitted second control signals, the second deflection unit is configured to perform a sinusoidal second movement, in particular a second rotational movement, about a second axis, especially a vertical axis. Alternatively, only a single deflection unit, in particular a micromirror, with an associated drive unit is present, wherein the deflection unit is configured to perform both the rotational movement about the first and the second axis. The drive unit can, for example, be configured as a combined piezoelectric and electromagnetic drive. Description of the drawings Fig. Figure 1 schematically shows an embodiment of a computing unit for controlling at least one drive unit or at least one deflection unit of a two-dimensional microscanner device. Fig. Figure 2 schematically shows an embodiment of the microscanner device. Fig. Figure 3a shows a first embodiment of the method for controlling at least one drive unit and at least one deflection unit of a two-dimensional microscanner device. Fig. Figure 3b shows a second embodiment of the method. Fig. Figure 4a shows a possible signal pattern of the first movement. Fig. Figure 4b shows a corresponding possible signal pattern of the second movement. Fig. Figure 4c shows a corresponding possible course of the first control signals. Fig. 5a shows a section of an initial projected Lissajous figure. Fig. 5b shows a section of a second projected Lissajous figure. Fig. Figure 6 shows pixels in the form of a Lissajous figure on a projection unit. Exemplary embodiments of the invention

[0016] Fig. Figure 1 schematically shows an embodiment of a computing unit 10 for controlling at least one drive unit 30 and at least one deflection unit 25, in particular a micromirror, or a two-dimensional microscanner device. In this embodiment, the deflection unit 25 is configured as a single deflection unit 25, which is driven by a drive unit 30 configured as a combined piezoelectric 15 and electromagnetic drive 20. In this context, the computing unit 10 is configured to transmit first control signals 11 to the drive unit 30 at a first time to generate a sinusoidal first movement, in particular a first rotational movement, of the deflection unit 25 about a first axis, in particular about a horizontal axis.Additionally, the processing unit 10 serves to transmit second control signals 12 to the drive unit 30 at the first time point to generate a sinusoidal second movement, in particular a second rotational movement, of the deflection unit 25 about a second axis, in particular about a vertical axis. The first axis and the second axis are arranged essentially perpendicular to each other. The processing unit 10 is configured to adapt the first control signals 11 such that a periodic third movement is superimposed on the first movement at a second time point following the first time point. Alternatively, the processing unit 10 is configured to adapt the second control signals 12 such that a periodic fourth movement is superimposed on the second movement at a second time point following the first time point.

[0017] Optionally, the computing unit 10 is configured to transmit the first control signals 11 to at least one drive unit 30 in such a way that the sinusoidal first movement of the at least one deflection unit 25 about the first axis is resonant. In addition, the computing unit 10 serves in this context to adapt the first control signals 11 in such a way that a controlled third movement is superimposed on the first movement as a periodic third movement at the second time point following the first.

[0018] According to the invention, the processing unit 10 is configured to generate the first control signals 11 such that the sinusoidal first movement of the deflection unit 25 about the first axis occurs at a defined first frequency f1. The processing unit 10 is also configured to generate the second control signals 12 such that the sinusoidal second movement of the deflection unit 25 about the second axis occurs at a defined second frequency f2. Depending on the frequencies f1 and f2, pixels in the form of a Lissajous figure are then projected by means of the deflection unit 25 onto a provided, in particular rectangular, projection unit 35. The processing unit 10 is configured to determine the second time point following the first time point as a function of the temporal progression of the sinusoidal first and / or second movement of the deflection unit 25.In order for the processing unit 10 to know the temporal progression of the sinusoidal first and / or second movement of the deflection unit 25, a clock 5 is provided in this embodiment. Additionally, a sensor unit 6 is provided in this context, which is configured to detect the current rotation angle α1 of the deflection unit 25 about the first axis and the current rotation angle α2 of the deflection unit 25 about the second axis. The sensor unit 6 can, for example, be a camera unit or a capacitive sensor.

[0019] Fig. Figure 2 shows an embodiment of a microscanner device 40. A light unit 50, in particular a laser unit, of the microscanner device 40 is configured to emit light beams 70a onto a second deflection unit 60. A second drive unit 55 is associated with the second deflection unit 60. The processing unit 65 is configured to generate second control signals for controlling the second drive unit 55 of the second deflection unit 60. Depending on the second control signals transmitted via the transmission line 66, a sinusoidal second rotational movement of the second deflection unit 60 about a vertical axis as a second axis 57 is performed at a first time, depending on the transmitted second control signals. Due to the rotation of the second deflection unit 60, the light beam 70a is reflected in a horizontal trajectory onto the first deflection unit 61.The first deflection unit 61 is associated with a first drive unit 56. The processing unit 65 is configured to generate initial control signals for controlling the first drive unit 56 of the first deflection unit 67. Depending on the initial control signals transmitted via the transmission line 67, a sinusoidal initial rotation of the first deflection unit 61 about a horizontal axis, designated as the first axis 62, is performed at the first time. The additional rotation of the first deflection unit 61 about the first axis 62 projects the light beam 70b in the form of a Lissajous figure onto a designated rectangular projection unit 75.

[0020] The computing unit 65 is designed to adapt the first control signals in such a way that a periodic third movement is superimposed on the first movement at a second time point following the first time point.

[0021] Fig. Figure 3a shows, in the form of a flowchart, a first embodiment of a method for controlling at least one drive unit, at least one deflection unit, in particular a micromirror, of a two-dimensional microscanner device. In a process step 100, first control signals for controlling the drive unit of the at least one deflection unit are generated by means of at least one processing unit. In a subsequent process step 110, second control signals for controlling the drive unit of the at least one deflection unit are generated by means of the at least one processing unit. In a subsequent process step 120, the first control signals are transmitted from the at least one processing unit to the at least one drive unit. In a process step 130, the second control signals are transmitted from the at least one processing unit to the at least one drive unit.Depending on the transmitted first control signals, a sinusoidal first movement, in particular a first rotational movement, of the at least one deflection unit about a first axis, in particular a horizontal axis, is then performed at a first time point in a process step 140. Depending on the transmitted second control signals, a sinusoidal second movement, in particular a second rotational movement, of the at least one deflection unit about a second axis, in particular a horizontal axis, is then performed at a first time point in a process step 150. In a subsequent process step 220, the second control signals transmitted by the at least one processing unit to the at least one drive unit are adapted such that a periodic fourth movement is superimposed on the second movement at the second time point following the first time point. The process is then terminated.

[0022] In a process step 160 according to the invention, the at least one deflection unit undergoes a sinusoidal first movement about the first axis at a defined first frequency f1. In a subsequent process step 170 according to the invention, the at least one deflection unit undergoes a sinusoidal second movement about the second axis at a defined second frequency f2. Thereupon, in a process step 180, image points in the form of a Lissajous figure are projected onto a provided, in particular rectangular, projection volume by means of the deflection unit.

[0023] In an optional process step 190, the time is measured from the first time point using a clock. Since the processing unit knows the frequencies f1 and f2 of the first and second movements, the second time point can be determined by the processing unit based on the timing in process step 215. In a further process step 200, the rotation angle α1 of the at least one deflection unit about the first axis and the rotation angle α2 of the at least one deflection unit about the second axis are additionally recorded at the first time point using at least one sensor unit. The second time point can thus be determined even more precisely by the processing unit in process step 215.In a further process step 210, the rotation angle α1 of the at least one deflection unit about the first axis and the rotation angle α2 of the at least one deflection unit about the second axis are continuously detected by means of the at least one sensor unit.

[0024] In an optional process step 224, the second time point is set such that the fourth movement is superimposed on the second rotational movement about the second axis after half of a cycle of the projected Lissajous figure.

[0025] In a further optional process step 231, the second control signals are adjusted such that a periodic rectangular fourth movement is superimposed on the second movement. Alternatively, a periodic sinusoidal, triangular, or sawtooth-shaped third movement can also be superimposed as a periodic third movement.

[0026] In an optional process step 260, the superimposed fourth motion has a period T4 that corresponds to a plurality of the period T2 of the second motion.

[0027] Fig. Figure 3b shows, in the form of a flowchart, a second embodiment of the method for controlling at least one drive unit, at least one deflection unit, in particular a micromirror, of a two-dimensional microscanner device. In contrast to the first embodiment, in process step 219 the first control signals transmitted from the at least one computing unit to the at least one drive unit are adapted such that a periodic third movement is superimposed on the first movement at a second time point following the first.

[0028] In an optional process step 221, the sinusoidal first movement of the at least one deflection unit about the first axis is carried out resonantly. In a subsequent process step 225, the first control signals are adjusted such that a controlled third movement is superimposed on the first movement as a periodic third movement at the second time point following the first time point.

[0029] In an optional process step 230, the first control signals are adjusted such that a periodic rectangular third movement is superimposed on the first movement. Alternatively, a periodic sinusoidal, triangular, or sawtooth-shaped third movement can also be superimposed.

[0030] In an optional process step 240, the sinusoidal first movement of the at least one deflection unit about the first axis has a period T1, depending on the transmitted first control signals. The first control signals are adjusted such that the periodic third movement generated at the second time point following the first has a period T3, such that the ratio of T1 to T3 is at least 1:8. In particular, the ratio is 1:1000.

[0031] Fig. Figure 4a schematically illustrates the progression of a sinusoidal first rotational movement 320a and 320b of at least one deflection unit about a first axis. The first axis is a horizontal axis. The rotation angle α1 of the deflection unit about the first axis is plotted on the Y-axis 345, and time is plotted on the X-axis 310. From a first time point 301 to a second time point 305, the sinusoidal first movement 320a proceeds uniformly with a constant first amplitude 355 and a constant period T1 360 around the zero crossing 350. From the second time point 305 onward, however, a third rectangular movement 330 is superimposed on the sinusoidal first movement 320a. This third movement represents a controlled movement.The resulting overall motion 320b is a sinusoidal rotational motion which, unlike the first rotational motion 320a, is shifted upwards by the total displacement 365 of the rectangular third motion. The zero crossing of the resulting overall motion 320b is correspondingly shifted upwards by the total displacement 365 of the rectangular third motion. In this embodiment, the period T3 328 of the third motion is four times longer than the period T1 360 of the first motion. The first rotational motion 320a about the first axis is resonant.

[0032] Fig. 4b shows a schematic example of the following: Fig. Figure 4a shows the sinusoidal second rotational movement of the at least one deflection unit about a vertical axis, corresponding to the first movement shown. The rotation angle α2 of the deflection unit about the second axis is plotted on the Y-axis 345, and time is plotted on the X-axis 310. The second movement 340 exhibits a uniform sinusoidal shape around the zero crossing 351 over the entire time course, with a second period T2 and a constant second amplitude 385. The second period T2 is significantly shorter than the first period T1.

[0033] Fig. Figure 4c schematically illustrates the course of the first control signals, which are generated by the processing unit to control at least one drive unit or at least one deflection unit, so that the rotary motion is as shown. Fig. As shown in Figure 4a, the process can be carried out. The Y-axis (400) represents the control voltage and the X-axis represents time. In contrast to the one shown in Figure 4a, the following applies: Fig. In the sinusoidal motion sequence 320a and 320b shown in Figure 4a, the signal waveform 420a and 420b is rectangular. The period 405 to 415 corresponds to the period from the first time point 301 to the second time point 305. Fig. 4a, however, the rotational movement 320a and 320b is only carried out with a time delay after the first control signals 420a and 420b have been generated. The signal waveform 420a runs periodically around the control voltage 401 as a zero crossing. The control voltage 401 generates a rotation angle α1, which corresponds to the zero crossing 350. Fig. 4a corresponds.

[0034] Fig. Figure 5a shows a section of the trajectory paths 455a and 455b of the projected pixels in the form of a Lissajous figure. The section of the Lissajous figure shown here was generated at a frequency ratio f1 (frequency of movement around the horizontal axis) to f2 (frequency of movement around the vertical axis) of 10.2:1. This means the Lissajous figure required 5 passes to complete and generate an image. However, no adjustments were made to the initial control signals. Trajectory 455a represents the outward path, i.e., the pass of the Lissajous figure from bottom to top, and trajectory 455b represents the return path, i.e., the pass of the Lissajous figure from top to bottom. On the axis in the Y direction 450a, there is an intersection 460 of the trajectories 455a and 455b, so that the Y-axis is intersected a total of 10 times on the section shown.

[0035] Fig. Figure 5b shows a section of the trajectory paths 456a and 456b of the projected pixels in the form of a Lissajous figure. Trajectory 456a represents the outward path, i.e., the traversal of the Lissajous figure from bottom to top, and trajectory 456b represents the return path, i.e., the traversal of the Lissajous figure from top to bottom. Here too, the section shown corresponds to a Lissajous figure generated at a frequency ratio f1 (frequency of movement around the horizontal axis) to f2 (frequency of movement around the vertical axis) of 10.2:1. This means that the Lissajous figure required 5 passes to be completed and to generate an image. In contrast to... Fig. 5a. An adjustment of the first control signals was made so that after 2.5 iterations of the Lissajous figure, a periodic rectangular third motion was superimposed on the first motion. Trajectory 456b is thus shifted upwards by the amplitude of the superimposed rectangular third motion, unlike trajectory 455b. This results in trajectories 456a and 456b scanning the image much more homogeneously, and the axis in the Y-direction 450a is intersected a total of 15 times by trajectories 456a and 456b. Larger areas 461, which were not described in this iteration of the Lissajous figure, can be described in the next iteration by adjusting the first control signals and subsequently modifying the superimposed third motion, so that on average all areas are described.

[0036] Fig.Figure 6 schematically shows a projection unit 500 onto which pixels in the form of a Lissajous figure 510 are projected. In this case, the first control signals are adapted such that a periodic sinusoidal third motion is superimposed on the first motion. The superimposed sinusoidal third motion has a period T3 that is equal to the period T1 of the first motion. However, the superimposed sinusoidal third motion is phase-shifted relative to the first motion.

Claims

[1] Method for controlling at least one drive unit (30, 55, 56) and at least one deflection unit (25, 60, 61), in particular a micromirror, a two-dimensional microscanner device (40), the method comprising the following process steps: - Generating (100) first control signals (11, 420a, 420b) for controlling the drive unit (30, 55, 56) of the at least one deflection unit (25, 60, 61) by means of at least one computing unit (10, 65), and - Generating (110) second control signals (12) for controlling the drive unit (30, 55, 56) of the at least one deflection unit (25, 60, 61) by means of the at least one computing unit (10, 65), and - Transmitting (120) the first control signals (11, 420a, 420b) from the at least one computing unit (10, 65) to the at least one drive unit (30, 55, 56), and - Transmitting (130) the second control signals (12) from the at least one computing unit (10, 65, 76) to the at least one drive unit (25, 60, 61), and - Execution (130) of a sinusoidal first motion (320a), in particular a first rotational motion, of which at least one deflection unit (25, 60, 61) about a first axis (62), in particular a horizontal axis, depending on the transmitted first control signals (11, 420a, 420b) at a first time (301), and - Execution (140) of a sinusoidal second motion (340), in particular a second rotational motion, which includes at least one deflection unit (25, 60, 61) about a second axis (57) arranged substantially perpendicular to the first axis (62), in particular about a vertical axis, at the first time (301), wherein the first control signals (11, 420a, 420b) transmitted from the at least one computing unit (10, 65) to the at least one drive unit (25, 60, 61) are adapted (219) such that a periodic third movement (330) is superimposed on the first movement (320a) at a second time (305) following the first time (301), or wherein the second control signals (12) transmitted from the at least one computing unit (10, 65) to the at least one drive unit (25, 60, 61) are adapted (220) such that a periodic fourth movement is superimposed on the second movement (340) at the second time (305) following the first time (301), characterized by , that the sinusoidal first motion (320a) of the at least one deflection unit (25, 60, 61) about the first axis (62) is performed with a defined first frequency f1 (160), and the sinusoidal second motion of the at least one deflection unit (25, 60, 61) about the second axis (57) is performed with a defined second frequency f2 (170), wherein, depending on the frequencies f1 and f2, image points in the form of a Lissajous figure (455a, 455b, 456a, 456b, 510) are projected onto a provided, in particular rectangular, projection volume (500) by means of the deflection unit (25, 60, 61) (180). [2] Method according to claim 1, characterized by, that the sinusoidal first movement (320a) of the at least one deflection unit (25, 60, 61) about the first axis (62) is carried out resonantly depending on the transmitted first control signals (11, 420a, 420b) (221), and the first control signals (11, 420a, 420b) are adapted such that a controlled third movement as a periodic third movement (330) is superimposed on the first movement (320a) at the second time (305) following the first time (301) (225). [3] Method according to one of claims 1 or 2, characterized by, that the sinusoidal first motion (320a) of the at least one deflection unit (25, 60, 61) about the first axis (62) has a period T1 (360) depending on the transmitted first control signals (11, 420a, 420b), and the first control signals (11, 420a, 420b) are adapted such that the periodic third motion (330) generated at the second time (305) following the first time (301) has a period T3 (328), wherein the ratio of T1 (360) to T3 (328) is at least 1:8, in particular 1:1000 (240). [4] Method according to any one of claims 1 to 3, characterized by , that the first control signals (11, 420a, 420b) are adapted such that a periodic rectangular third movement (330) is superimposed on the first movement (320a) as a periodic third movement (330) (230), or the second control signals (12) are adjusted such that a periodic rectangular fourth movement is superimposed on the second movement (340) as a periodic fourth movement (231). [5] Method according to claim 1, characterized by , that the second time (305) following the first time (301) occurs depending on a temporal progression of the sinusoidal first (320a) and / or second motion (340) of the at least one deflection unit (25, 60, 61). [6] Method according to one of claims 1 or 5, characterized by , that the second time (305) following the first time (301) is determined depending on a rotation angle α1 of the at least one deflection unit (35, 60, 61) about the first axis (62) and / or a rotation angle α2 of the at least one deflection unit (25, 60, 61) detected at the first time (301) (215). [7] Method according to one of claims 1 or 5 to 6, characterized by , that the second time (305) following the first time (301) is determined (215) depending on a detected rotation angle α1 of the at least one deflection unit (25, 60, 61) about the first axis (62) and a detected (210) rotation angle α2 of the at least one deflection unit (25, 60, 61) about the second axis (57). [8] Computing unit (10, 65) for controlling at least one drive unit (30, 55, 56) and at least one deflection unit (25, 60, 61), in particular a micromirror, a two-dimensional microscanner device (40), wherein the computing unit (10, 65) is configured to - first control signals (11, 420a, 420b) for generating a sinusoidal first motion (320a), in particular a first rotational motion, to which at least one deflection unit (25, 60, 61) about a first axis (62), in particular about a horizontal axis, is to be transmitted at a first time (301) to the at least one drive unit (30, 55, 56), and - second control signals (12) for generating a sinusoidal second motion (340), in particular a second rotary motion, to which at least one deflection unit (30, 55, 56) about a second axis (57), in particular about a vertical axis, is transmitted at the first time (301) to the at least one drive unit (30, 55, 56), wherein the first axis (57) and the second axis (62) are arranged essentially perpendicular to each other, wherein the computing unit (10, 65) is configured to adapt the first control signals (11, 420a, 420b) such that a periodic third movement (330) is superimposed on the first movement (320a) at a second time point (305) following the first time point (301), or to adjust the second control signals (12) such that a periodic fourth movement is superimposed on the second movement (340) at the second time point (305) following the first time point (301), characterized by , that the computing unit (10, 65) is designed to, - to generate the first control signals (11, 420a, 420b) such that the sinusoidal first movement (320a) of the at least one deflection unit (25, 60, 61) about the first axis (62) occurs with a defined first frequency f1, and - to generate the second control signals (12) such that the sinusoidal second movement (340) of the at least one deflection unit (25, 60, 61) about the second axis (57) occurs with a defined second frequency f2, wherein, depending on the frequencies f1 and f2, image points in the form of a Lissajous figure (455a, 455b, 456a, 456b, 510) are projected onto a provided, in particular rectangular, projection unit (500) by means of the deflection unit (25, 60, 61), wherein the computing unit (10, 65) is configured to determine the second time point (305) following the first time point (301) depending on a temporal progression of the sinusoidal first (320a) and / or second motion (340) of the at least one deflection unit (25, 60, 61). [9] Computing unit (10, 65) according to claim 8, characterized by , that the computing unit (10, 65) is designed to, - to transmit the first control signals (11, 420a, 420b)) to at least one drive unit (30, 55, 56) in such a way that the sinusoidal first movement (320a) of the at least one deflection unit (25, 60, 61) about the first axis (62) is resonant, wherein the computing unit (10, 65) is designed to adapt the first control signals (11, 420a, 420b) in such a way that a controlled third movement (330) is superimposed as a periodic third movement on the first movement (320a) at the second time point (305) following the first time point (301). [10] Computing unit (10, 65) according to one of claims 8 or 9, characterized by, that the computing unit (10, 65) is configured to generate the first control signals (11, 420a, 420b) and transmit them to at least one drive unit (30, 55, 56) such that the sinusoidal first movement (320a) has a period T1 (360), wherein the computing unit (10, 65) is configured to adapt the first control signals (11, 420a, 420b) such that the periodic third movement (330) generated at the second time (305) following the first time (301) has a defined period T3 (328), wherein the ratio of T1 (360) to T3 (328) is at least 1:8, in particular 1:1000. [11] Computing unit (10, 65) according to one of claims 8 to 10, characterized by, that the computing unit (10, 65) is designed to adapt the first control signals (11, 420a, 420b) in such a way that a periodic rectangular third movement (330) is superimposed on the first movement (320a) at the second time point (305) following the first time point (301), or to adapt the second control signals (12) in such a way that a periodic rectangular fourth movement (340) is superimposed on the second movement (340) at the second time point (305) following the first time point (301). [12] Microscanner device (40) with a computing unit (10, 65, 67) according to one of claims 8 to 11. [13] Microscanner device according to claim 12 comprising a first deflection unit and a first drive unit associated with the first deflection unit and a second deflection unit and a second drive unit associated with the second deflection unit.

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