Patent Description:
Micromechanical scanning silicon mirrors typically include one or more piezoresistive sensors. A piezoresistive sensor of a micromechanical scanning silicon mirror can provide feedback for driving the micromechanical scanning silicon mirror and timing the scanning display projection system. A signal provided by the piezoresistive sensor can be relatively low level. Moreover, the signal from the piezoresistive sensor is often transmitted back to a drive circuit for processing (e.g., the drive circuit can amplify the signal, convert the signal to a digital signal, etc.). However, conventional signal paths between piezoresistive sensor(s) of a micromechanical scanning silicon mirror and a drive circuit commonly include relatively long wire bonds, circuit board traces, connectors, and/or cables. Further, the signal is susceptible to noise along the signal path. Thus, the relatively long length of a conventional signal path between a piezoresistive sensor and a drive circuit can detrimentally impact the signal to noise ratio of the signal being provided from the piezoresistive sensor to the drive circuit.

<CIT> discloses an actuator, which includes: a weight part; a supporting part supporting the weight part; a connecting part coupling the weight part rotatable to the supporting part and having an elastic part; a driving member for driving and rotating the weight part; and a semiconductor circuit for driving the weight part.

<CIT> discloses strain-based sensing of mirror position.

<CIT> discloses a MEMS optical scanner that stably performs a scan with light by rotary moving a mirror centering on a V-axis in coincidence with a resonant frequency that enables ramp wave driving while securing shock resistance.

The present invention provides an apparatus according to claim <NUM>. Certain more specific aspects of the invention are set out in the dependent claims.

Described herein are various technologies that pertain to an apparatus for a scanning display projection system. The apparatus includes a micromechanical scanning silicon mirror and a signal processing device. The micromechanical scanning silicon mirror and the signal processing device are part of separate dies. Moreover, the signal processing device is collocated with the micromechanical scanning silicon mirror. The micromechanical scanning silicon mirror can include a mirror section, a first foot, a second foot, a first flexure, and a second flexure. The first flexure is between the mirror section and the first foot, with a distal end of the first flexure terminating at the first foot. Moreover, the second flexure is between the mirror section and the second foot, with a distal end of the second flexure terminating at the second foot. The micromechanical scanning silicon mirror further includes a piezoresistive sensor (or a plurality of piezoresistive sensors) and sensor contacts, where the sensor contacts are electrically coupled to the piezoresistive sensor(s). The apparatus includes wire bonds. The wire bonds are directly connected between the sensor contacts of the micromechanical scanning silicon mirror and the signal processing device. In accordance with various examples where the apparatus includes wire bonds, the signal processing device can be mounted on the micromechanical scanning silicon mirror (e.g., mounted on the first foot of the micromechanical scanning silicon mirror), mounted on a frame adjacent to the micromechanical scanning silicon mirror (e.g., adjacent to the first foot of the micromechanical scanning silicon mirror), or mounted on a printed circuit board. Thus, a length of a signal path between the piezoresistive sensor and the signal processing device can be shorter than a conventional signal path between a piezoresistive sensor and a drive circuit, which can improve the signal to noise ratio of the signal from the piezoresistive sensor relative to conventional approaches.

Pursuant to various examples, an apparatus can include the micromechanical scanning silicon mirror and the signal processing device, which are part of separate dies and collocated with each other. The micromechanical scanning silicon mirror can include the mirror section, the first foot, the second foot, the first flexure, the second flexure, the piezoresistive sensor(s), and the sensor contacts. According to theseexamples, the signal processing device can be mounted on the micromechanical scanning silicon mirror. For instance, the signal processing device can be mounted on the first foot of the micromechanical scanning silicon mirror. Moreover, the signal processing device can be electrically coupled to the sensor contacts of the micromechanical scanning silicon mirror. According to an example, wire bonds can electrically couple the signal processing device and the sensor contacts by being directly connected between the sensor contacts of the micromechanical scanning silicon mirror and the signal processing device. Pursuant to another example, the signal processing device can be mounted on the first foot of the micromechanical scanning silicon mirror via connectors, where the connectors both mechanically and electrically connect the micromechanical scanning silicon mirror and the signal processing device. Mounting the signal processing device on the micromechanical scanning silicon mirror can decrease a length of a signal path relative to a conventional signal path between a piezoresistive sensor and a drive circuit, thus leading to improvement in the signal to noise ratio of the signal from the piezoresistive sensor as compared to conventional approaches.

Various technologies pertaining to collating a signal processing device with a micromechanical scanning silicon mirror as part of an apparatus for a scanning display projection system are now described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. In other instances, well-known structures and devices are shown in block diagram form in order to facilitate describing one or more aspects. Further, it is to be understood that functionality that is described as being carried out by certain system components may be performed by multiple components. Similarly, for instance, a component may be configured to perform functionality that is described as being carried out by multiple components.

Referring now to the drawings, <FIG> illustrates an apparatus <NUM> that can be part of a scanning display projection system. The apparatus <NUM> includes a micromechanical scanning silicon mirror <NUM> and a signal processing device <NUM>. The signal processing device <NUM> is collocated with the micromechanical scanning silicon mirror <NUM> in the apparatus <NUM>.

The micromechanical scanning silicon mirror <NUM> and the signal processing device <NUM> are part of separate dies. The micromechanical scanning silicon mirror <NUM> and the signal processing device <NUM> may be included in separate dies since fabrication processes used to build a micromechanical scanning silicon mirror and a signal processing device can significantly differ. Thus, rather than relying on a more complex fabrication process, two separate fabrication processes tailored specifically for the intended applications can be utilized to separately build the micromechanical scanning silicon mirror <NUM> and the signal processing device <NUM>.

A direct electrical connection exists between the micromechanical scanning silicon mirror <NUM> and the signal processing device <NUM> in the apparatus <NUM>. For instance, wire bonds can be directly between the micromechanical scanning silicon mirror <NUM> and the signal processing device <NUM>. Additionally or alternatively, the signal processing device <NUM> can be mounted on the micromechanical scanning silicon mirror <NUM>; in addition to being mounted on the micromechanical scanning silicon mirror <NUM>, the signal processing device <NUM> can be electrically coupled to the micromechanical scanning silicon mirror <NUM> (e.g., via wire bonds, via connectors that both mechanically and electrically connect the signal processing device <NUM> and the micromechanical scanning silicon mirror <NUM>).

The apparatus <NUM> can further include a frame <NUM>, a printed circuit board <NUM>, and a drive circuit <NUM>. The frame <NUM> is configured to tilt relative to the printed circuit board <NUM>. Moreover, the micromechanical scanning silicon mirror <NUM> is mounted on the frame <NUM>; thus, tilting of the frame <NUM> relative to the printed circuit board <NUM> can cause tilting of the micromechanical scanning silicon mirror <NUM>. Further, the drive circuit <NUM> can control the tilt of the frame <NUM> (e.g., control an actuator to cause the frame <NUM> to move relative to the printed circuit board <NUM>).

The micromechanical scanning silicon mirror <NUM> includes a piezoresistive sensor. While many of the examples of the apparatus <NUM> set forth herein describe a micromechanical scanning silicon mirror that includes one piezoresistive sensor, it is contemplated that these examples can be extended to embodiments where the micromechanical scanning silicon mirror includes more than one piezoresistive sensor (e.g., a biaxial micromechanical scanning silicon mirror that includes two piezoresistive sensors can replace the linear micromechanical scanning silicon mirror described in many of the examples). The piezoresistive sensor, for example, can provide feedback (e.g., transmitted to the drive circuit <NUM>) for driving the micromechanical scanning silicon mirror <NUM>.

A signal outputted by the piezoresistive sensor can be a relatively low level signal to be transmitted back to the drive circuit <NUM>. According to an example, the signal outputted by the piezoresistive sensor can be a differential signal. Following this example, the signal outputted by the piezoresistive sensor can include a reference voltage, ground, and differential outputs (+IN and -IN) (e.g., the reference voltage, ground, and differential outputs can be inputted to the signal processing device <NUM>). However, the claimed subject matter is not so limited.

Conventionally, a signal path for a feedback signal from a piezoresistive sensor to a drive circuit may be relatively long. For instance, a conventional signal path may include long wire bonds (e.g., from a micromechanical scanning silicon mirror to a printed circuit board), circuit board traces, connectors, and cables before signal processing is performed. With such conventional designs, the possibility of noise being added to the signal exists. Moreover, a piezoresistive sensor can have relatively high output impedance.

To address the foregoing, the apparatus <NUM> includes a direct electrical connection between the signal processing device <NUM> and the micromechanical scanning silicon mirror <NUM>. The techniques described herein allow for decreasing the length of the signal path, while allowing for the micromechanical scanning silicon mirror <NUM> to continue to be physically moved and subject to dynamic physical stresses. Thus, a length of a signal path from the piezoresistive sensor to a device that processes the signal outputted by the piezoresistive sensor is decreased, which lowers noise introduced to such signal. Physically locating the signal processing device <NUM> close to the piezoresistive sensor of the micromechanical scanning silicon mirror <NUM> can decrease risk of introducing noise into the signal provided by the piezoresistive sensor used for feedback.

Various types of signal processing devices may be used. The signal processing device <NUM> can be an analog signal processing device, a digital signal processing device, or a combination thereof. For example, the signal processing device <NUM> can be an amplifier. According to another example, the signal processing device <NUM> can be a comparator. Pursuant to yet another example, the signal processing device <NUM> can be a buffer. According to yet another example, the signal processing device <NUM> can be an analog to digital converter. In accordance with yet a further example, the signal processing device <NUM> can linearize the signal from the piezoresistive sensor. However, it is contemplated that other types of signal processing devices may be used.

Now turning to <FIG>, illustrated is an exemplary micromechanical scanning silicon mirror <NUM> (e.g., the micromechanical scanning silicon mirror <NUM> of <FIG>). A top view and an end view of the micromechanical scanning silicon mirror <NUM> are depicted in <FIG>.

The micromechanical scanning silicon mirror <NUM> includes a mirror section <NUM>, a first foot <NUM>, a second foot <NUM>, a first flexure <NUM>, and a second flexure <NUM>. The first foot <NUM> and the second foot <NUM> are collectively referred to herein as feet <NUM>-<NUM>, and the first flexure <NUM> and the second flexure <NUM> are collectively referred to herein as flexures <NUM>-<NUM>. The first flexure <NUM> is between the mirror section <NUM> and the first foot <NUM>. A distal end of the first flexure <NUM> terminates at the first foot <NUM>. Moreover, the second flexure <NUM> is between the mirror section <NUM> and the second foot <NUM>. A distal end of the second flexure <NUM> terminates at the second foot <NUM>. In the exemplary micromechanical scanning silicon mirror <NUM> depicted in <FIG>, a proximal end of the first flexure <NUM> terminates at the mirror section <NUM>, and a proximal end of the second flexure <NUM> terminates at the mirror section <NUM>.

The micromechanical scanning silicon mirror <NUM> further includes a piezoresistive sensor <NUM> and sensor contacts, namely, a sensor contact <NUM>, a sensor contact <NUM>, a sensor contact <NUM>, and a sensor contact <NUM> (collectively referred to herein as sensor contacts <NUM>-<NUM>). The sensor contacts <NUM>-<NUM> are electrically coupled to the piezoresistive sensor <NUM>. While one piezoresistive sensor <NUM> and four sensor contacts <NUM>-<NUM> are included in the exemplary micromechanical scanning silicon mirror <NUM>, it is contemplated that other micromechanical scanning silicon mirrors can include more than one piezoresistive sensor and/or more (or less) than four sensor contacts <NUM>-<NUM>.

<FIG> also depicts an exploded view <NUM> of the piezoresistive sensor <NUM>. As shown, the piezoresistive sensor <NUM> can include four resistors, namely, a resistor <NUM>, a resistor <NUM>, a resistor <NUM>, and a resistor <NUM> (collectively referred to herein as resistors <NUM>-<NUM>). The resistor <NUM> and the resistor <NUM> are connected at a node <NUM>, the resistor <NUM> and the resistor <NUM> are connected at a node <NUM>, the resistor <NUM> and the resistor <NUM> are connected at a node <NUM>, and the resistor <NUM> and the resistor <NUM> are connected at a node <NUM>. The sensor contacts <NUM>-<NUM> can respectively be electrically coupled to the nodes <NUM>, <NUM>, <NUM>, and <NUM>.

The first foot <NUM> of the micromechanical scanning silicon mirror <NUM> can include the sensor contacts <NUM>-<NUM>. Moreover, the piezoresistive sensor <NUM> can be located at the distal end of the first flexure <NUM>. The piezoresistive sensor <NUM> being located at the distal end of the first flexure <NUM> can include the piezoresistive sensor <NUM> being included in the first flexure <NUM> near the distal end of the first flexure <NUM>, the piezoresistive sensor <NUM> being included in the first foot <NUM> near the first flexure <NUM>, or a portion of the piezoresistive sensor <NUM> being included in the first flexure <NUM> near the distal end and another portion of the piezoresistive sensor <NUM> being included in the first foot <NUM> near the first flexure <NUM>.

The flexures <NUM>-<NUM> are flexible elements designed to be compliant in specific degrees of freedom. In the example of <FIG>, the flexures <NUM>-<NUM> of the micromechanical scanning silicon mirror <NUM> are linearly aligned such that first foot <NUM> is connected to the first flexure <NUM>, the first flexure <NUM> is connected to the mirror section <NUM>, the mirror section <NUM> is connected to the second flexure <NUM>, and the second flexure <NUM> is connected to the second foot <NUM>. While the flexures <NUM>-<NUM> are depicted as being linear flexures, it is also contemplated that flexures having other shapes can alternatively be included in the micromechanical scanning silicon mirror <NUM>; for example, flexures can be curved or s-shaped to fit the micromechanical scanning silicon mirror <NUM> in a different aspect ratio shape. The micromechanical scanning silicon mirror <NUM> is designed such that, when rocked at an appropriate resonance frequency, a tilt angle of the mirror section <NUM> is larger than a tilt angle of the feet <NUM>-<NUM>. A tilt angle can be detected by use of the piezoresistive sensor <NUM> located at the distal end of the first flexure <NUM>. Thus, the piezoresistive sensor <NUM> can provide feedback for a drive circuit (e.g., the drive circuit <NUM>) and for a display system.

According to an example, the mirror section <NUM> can have a diameter of approximately <NUM>; however, it is to be appreciated that other diameters of the mirror section <NUM> are possible (e.g., the mirror section <NUM> can have a diameter of approximately <NUM>, approximately <NUM>, etc.). In accordance with an example, a length of micromechanical scanning silicon mirror <NUM> can be <NUM>-<NUM>. Pursuant to an example, a width of the micromechanical scanning silicon mirror <NUM> can be <NUM>-<NUM>. However, it is to be appreciated that other dimensions of the micromechanical scanning silicon mirror <NUM> are possible.

<FIG> shows a top view of an exemplary apparatus <NUM> that includes the micromechanical scanning silicon mirror <NUM>, the frame <NUM>, and the printed circuit board <NUM>. The apparatus <NUM> shown in <FIG> does not include the signal processing device <NUM>. The micromechanical scanning silicon mirror <NUM> is mounted on the frame <NUM> (e.g., the feet <NUM>-<NUM> are mounted on the frame <NUM>). The micromechanical scanning silicon mirror <NUM> can be mounted on the frame <NUM> via die attach adhesive, solder, or substantially any die stacking technique.

The frame <NUM> (with the micromechanical scanning silicon mirror <NUM> mounted thereon) is configured to tilt relative to the printed circuit board <NUM>. It is to be appreciated that the printed circuit board <NUM> and the frame <NUM> continue to the left and right (beyond the portions depicted in <FIG>), where a mechanism (e.g., an actuator) that causes the tilting is located.

The apparatus <NUM> further includes wire bonds, namely, a wire bond <NUM>, a wire bond <NUM>, a wire bond <NUM>, and a wire bond <NUM> (collectively referred to herein as wire bonds <NUM>-<NUM>). The wire bonds <NUM>-<NUM> are between the sensor contacts <NUM>-<NUM> and the printed circuit board <NUM>. Thus, the wire bonds <NUM>-<NUM> are part of a signal path from the piezoresistive sensor <NUM>. However, as described herein, it can be desired to shorten the signal path to improve the signal to noise ratio of the signal from the piezoresistive sensor <NUM>.

Now turning to <FIG>, illustrated are end views of the apparatus <NUM> of <FIG>. View <NUM> shows the apparatus <NUM> with an actuator at rest, and views <NUM> and <NUM> show the apparatus <NUM> at different times when the actuator is driven. Again, the apparatus <NUM> shown in <FIG> does not include the signal processing device <NUM>.

As depicted, the micromechanical scanning silicon mirror <NUM> is mounted on the frame <NUM>. The micromechanical scanning silicon mirror <NUM> (e.g., the feet <NUM>-<NUM>) and the frame <NUM> are attached by a layer <NUM>. The layer <NUM>, for example, can be die attach adhesive or solder; however, substantially any die stacking technique can be utilized to mount the micromechanical scanning silicon mirror <NUM> on the frame <NUM> via the layer <NUM>. Moreover, the wire bonds <NUM>-<NUM> are between the micromechanical scanning silicon mirror <NUM> (e.g., the sensor contacts <NUM>-<NUM>) and the printed circuit board <NUM>.

When in operation (e.g., when the actuator is driven), as shown in views <NUM> and <NUM>, the frame <NUM> can tilt relative to the printed circuit board <NUM>. Tilting of the frame <NUM> causes tilting of the micromechanical scanning silicon mirror <NUM> relative to the printed circuit board <NUM>. In the apparatus <NUM>, a signal from the piezoresistive sensor <NUM> can be carried from the micromechanical scanning silicon mirror <NUM> to the printed circuit board <NUM> by way of wire bonds <NUM>-<NUM>. The signal path from the piezoresistive sensor <NUM> can further include circuit board traces included in the printed circuit board <NUM>, connectors, and/or cables. Thus, the relatively long length of the signal path for the apparatus <NUM> (e.g., between the piezoresistive sensor <NUM> and a drive circuit) can detrimentally impact the signal to noise ratio of the signal provided from the piezoresistive sensor <NUM>.

With reference to <FIG>, illustrated is an exemplary circuit <NUM> that includes the piezoresistive sensor <NUM> and an amplifier <NUM>. The piezoresistive sensor <NUM> has a bridge structure, and includes the resistors <NUM>-<NUM>. The resistors <NUM>-<NUM> can have approximately equivalent resistance values.

A reference voltage is applied across the piezoresistive sensor <NUM>. For instance, +V is applied at the node <NUM>, and the node <NUM> is grounded. Moreover, the piezoresistive sensor <NUM> performs bridge measurements, with the bridge being connected to inputs of the amplifier <NUM>. Thus, the piezoresistive sensor <NUM> provides differential inputs (+IN and -IN) to the amplifier <NUM>. The circuit <NUM> includes paths <NUM> and <NUM>. The lengths of the paths <NUM> and <NUM> are desirably minimized utilizing the techniques described herein to lower noise introduced to the differential inputs along the paths <NUM> and <NUM> from the piezoresistive sensor <NUM> to the amplifier <NUM>. Moreover, it is to be appreciated that the paths <NUM> and <NUM> can carry the signal to other types of signal processing devices other than an amplifier in other embodiments.

The amplifier <NUM> (or other types of signal processing device) can convert a relatively high output impedance interface of the piezoresistive sensor <NUM> to a lower output impedance interface (e.g., the output impedance of the amplifier <NUM> can be lower than the output impedance of the piezoresistive sensor <NUM>), which can improve the signal to noise ratio for a signal outputted by the amplifier <NUM>. Moreover, it is contemplated that other types of signal processing devices can perform other processing of the signal from the piezoresistive sensor <NUM> to likewise lower the output impedance and improve the signal to noise ratio.

With reference to <FIG>, illustrated is an exemplary apparatus <NUM> according to the claimed invention (e.g., the apparatus <NUM> of <FIG>) that includes the micromechanical scanning silicon mirror <NUM>, the frame <NUM>, and the printed circuit board <NUM>. <FIG> shows a top view, an end view, and a side view of the apparatus <NUM>. It is to be appreciated that the top view and the side view of <FIG> only show a portion of the micromechanical scanning silicon mirror <NUM> (e.g., the second foot <NUM> can be mounted on the frame <NUM> as shown in <FIG>). Similar to above with respect to the apparatus <NUM>, the micromechanical scanning silicon mirror <NUM> is mounted on the frame <NUM> (e.g., the feet <NUM>-<NUM> are mounted on the frame <NUM>) in the apparatus <NUM>; the layer <NUM> attaches the micromechanical scanning silicon mirror <NUM> to the frame <NUM>.

In contrast to the apparatus <NUM> which lacks the signal processing device <NUM>, the apparatus <NUM> includes the signal processing device <NUM>. The signal processing device <NUM> is collocated with the micromechanical scanning silicon mirror <NUM> in the apparatus <NUM>.

In the apparatus <NUM> depicted in <FIG>, the signal processing device <NUM> is mounted on the first foot <NUM> of the micromechanical scanning silicon mirror <NUM>. While depicted as being mounted on the first foot <NUM> of the micromechanical scanning silicon mirror <NUM>, it is contemplated that the signal processing device <NUM> can additionally or alternatively be mounted on a different portion of the micromechanical scanning silicon mirror <NUM> other than the first foot <NUM> in other embodiments. The signal processing device <NUM> and the micromechanical scanning silicon mirror <NUM> (e.g., the first foot <NUM>) can be attached by a layer <NUM>. The layer <NUM>, for example, can be die attach tape or adhesive. Accordingly, the signal processing device <NUM> can be mounted directly on the first foot <NUM> of the micromechanical scanning silicon mirror <NUM> using the die attach tape or adhesive, which can be flexible enough to not transmit strain in the first foot <NUM> to the signal processing device <NUM> attached thereto. It is contemplated, however, that substantially any die stacking technique can be utilized to mount the signal processing device <NUM> on the micromechanical scanning silicon mirror <NUM>, and thus, the claimed subject matter is not limited to use of die attach tape or adhesive.

Moreover, the signal processing device <NUM> is electrically coupled to the sensor contacts <NUM>-<NUM> of the micromechanical scanning silicon mirror <NUM>. The apparatus <NUM> includes wire bonds that electrically couple the signal processing device <NUM> and the sensor contacts <NUM>-<NUM> of the micromechanical scanning silicon mirror <NUM>, namely, a wire bond <NUM>, a wire bond <NUM>, a wire bond <NUM>, and a wire bond <NUM> (collectively referred to herein as wire bonds <NUM>-<NUM>). The wire bonds <NUM>-<NUM> are directly connected between the sensor contacts <NUM>-<NUM> and the signal processing device <NUM>. Moreover, the apparatus <NUM> includes longer wire bonds that electrically couple the signal processing device <NUM> to the printed circuit board <NUM>, namely, a wire bond <NUM>, a wire bond <NUM>, a wire bond <NUM>, and a wire bond <NUM> (collectively referred to herein as wire bonds <NUM>-<NUM>). The wire bonds <NUM>-<NUM> between the signal processing device <NUM> and the printed circuit board <NUM> can be longer than the wire bonds <NUM>-<NUM> between the micromechanical scanning silicon mirror <NUM> and the signal processing device <NUM>. The wire bonds <NUM>-<NUM> can be longer to allow for tilting of the frame <NUM> (as well as the micromechanical scanning silicon mirror <NUM> and the signal processing device <NUM>) relative to the printed circuit board <NUM>. After signal processing by the signal processing device <NUM>, a feedback signal outputted by the signal processing device <NUM> can be less susceptible to noise as compared to a signal provided by the piezoresistive sensor <NUM>, and thus, the feedback signal can be carried to the printed circuit board <NUM> by way of the longer wire bonds <NUM>-<NUM>.

Turning to <FIG>, illustrated is another exemplary apparatus <NUM> not forming part of the claimed invention (e.g., the apparatus <NUM> of <FIG>) in which the signal processing device <NUM> is collocated with the micromechanical scanning silicon mirror <NUM>. A top view, an end view, and a side view of the apparatus <NUM> are depicted in <FIG> (with only a portion of the micromechanical scanning silicon mirror <NUM> being shown in the top view and the side view). Similar to the apparatus <NUM>, the apparatus <NUM> includes the signal processing device <NUM>, the micromechanical scanning silicon mirror <NUM>, the frame <NUM>, and the printed circuit board <NUM>. Further, similar to above, the micromechanical scanning silicon mirror <NUM> is mounted on the frame <NUM> via the layer <NUM>.

Similar to the apparatus <NUM>, the signal processing device <NUM> is mounted on the first foot <NUM> of the micromechanical scanning silicon mirror <NUM> in the apparatus <NUM>. Moreover, the signal processing device <NUM> is electrically coupled to the sensor contacts <NUM>-<NUM> of the micromechanical scanning silicon mirror <NUM>. In the apparatus <NUM> shown in <FIG>, the signal processing device <NUM> is mounted on the first foot <NUM> of the micromechanical scanning silicon mirror <NUM> via connectors, namely, a connector <NUM>, a connector <NUM>, a connector <NUM>, and a connector <NUM> (collectively referred to herein as connectors <NUM>-<NUM>). The connectors <NUM>-<NUM> both mechanically and electrically connect the micromechanical scanning silicon mirror <NUM> and the signal processing device <NUM>. According to various examples, the connectors <NUM>-<NUM> can include solder bumps, gold stud bumps, or copper pillars.

The connectors <NUM>-<NUM> can serve as both mechanical and electrical connections between the signal processing device <NUM> and the micromechanical scanning silicon mirror <NUM>. Although not shown, pursuant to an example, it is contemplated that the signal processing device <NUM> can be isolated from strain of the first foot <NUM> of the micromechanical scanning silicon mirror <NUM> by including a compliant layer between the connectors <NUM>-<NUM> and the signal processing device <NUM>. The foregoing can be accomplished in die and wafer level packaging. However, it is to be appreciated that the claimed subject matter is not limited to the foregoing example.

The apparatus <NUM> includes the connectors <NUM>-<NUM> rather than the shorter wire bonds <NUM>-<NUM> and the die attached tape or adhesive (e.g., the layer <NUM>), as included in the apparatus <NUM>. Moreover, similar to the apparatus <NUM>, the apparatus <NUM> includes the longer wire bonds <NUM>-<NUM> between the signal processing device <NUM> and the printed circuit board <NUM>.

<FIG> illustrate yet other exemplary apparatuses according to the claimed invention (e.g., the apparatus <NUM>) in which the signal processing device <NUM> is collocated with the micromechanical scanning silicon mirror <NUM>. In the examples shown in <FIG>, wire bonds are directly between the sensor contacts <NUM>-<NUM> of the micromechanical scanning silicon mirror <NUM> and the signal processing device <NUM>. Moreover, in the examples depicted in <FIG>, the signal processing device <NUM> is physically nearby the piezoresistive sensor <NUM> without being mounted on the micromechanical scanning silicon mirror <NUM>.

Now turning to <FIG>, illustrated is an exemplary apparatus <NUM> (e.g., the apparatus <NUM>). The apparatus <NUM> includes the micromechanical scanning silicon mirror <NUM> mounted on the frame <NUM> (e.g., attached via the layer <NUM>). The apparatus <NUM> also includes the signal processing device <NUM> mounted on the printed circuit board <NUM> (e.g., attached via a layer <NUM>). Again, substantially any type of die stacking technique can be utilized to mount the signal processing device <NUM> on the printed circuit board <NUM>.

The apparatus <NUM> further includes wire bonds, namely, a wire bond <NUM>, a wire bond <NUM>, a wire bond <NUM>, and a wire bond <NUM> (collectively referred to herein as wire bonds <NUM>-<NUM>). The wire bonds <NUM>-<NUM> are directly between sensor contacts (e.g., the sensor contacts <NUM>-<NUM>) of the micromechanical scanning silicon mirror <NUM> and the signal processing device <NUM>.

The signal processing device <NUM> can be mounted on the printed circuit board <NUM> near the piezoresistive sensor <NUM> and the sensor contacts <NUM>-<NUM>. While the signal path from the piezoresistive sensor <NUM> to the signal processing device <NUM> may be longer in the apparatus <NUM> relative to the signal path from the piezoresistive sensor <NUM> to the signal processing device <NUM> in the apparatus <NUM> or in the apparatus <NUM>, the signal path may be shorter in the apparatus <NUM> in comparison to conventional approaches, which may include circuit board traces on the printed circuit board <NUM>, etc. Thus, the wire bonds <NUM>-<NUM> directly between the sensor contacts and the signal processing device <NUM>, along with the signal processing device <NUM> being on the printed circuit board <NUM> near the piezoresistive sensor <NUM> and the sensor contacts <NUM>-<NUM>, can cause less noise to be introduced to the signal provided by the piezoresistive sensor <NUM> as compared to conventional approaches.

With reference to <FIG>, illustrated is another exemplary apparatus according to the claimed invention <NUM> (e.g., the apparatus <NUM>) in which the signal processing device <NUM> is collocated with the micromechanical scanning silicon mirror <NUM>. <FIG> shows a top view and a side view of the apparatus <NUM> (again with only a portion of the micromechanical scanning silicon mirror <NUM> being shown). The apparatus <NUM> includes the micromechanical scanning silicon mirror <NUM> mounted on the frame <NUM> (e.g., the feet <NUM>-<NUM> are mounted on the frame <NUM>). Similar to above, the micromechanical scanning silicon mirror <NUM> is attached to the frame <NUM> via the layer <NUM>.

The apparatus <NUM> also includes the signal processing device <NUM>. In the example of <FIG>, the signal processing device <NUM> is mounted on the frame <NUM> adjacent to the first foot <NUM> of the micromechanical scanning silicon mirror <NUM> (e.g., attached via a layer <NUM>). Similar to above, substantially any type of die stacking technique can be utilized to mount the signal processing device <NUM> on the frame <NUM>. It is contemplated that the signal processing device <NUM> and the micromechanical scanning silicon mirror <NUM> can be positioned at other locations relative to each other on the frame <NUM>, and thus, the claimed subject matter is not limited to the orientation depicted in <FIG> (e.g., the signal processing device <NUM> can be positioned to the left or right of the first foot <NUM> on the frame <NUM> as shown in the top view of <FIG>).

The apparatus <NUM> can further includes wire bonds, namely, a wire bond <NUM>, a wire bond <NUM>, a wire bond <NUM>, and a wire bond <NUM> (collectively referred to herein as wire bonds <NUM>-<NUM>). The wire bonds <NUM>-<NUM> are directly between the sensor contacts <NUM>-<NUM> of the micromechanical scanning silicon mirror <NUM> and the signal processing device <NUM>. Moreover, the apparatus <NUM> can include other wire bonds that are longer than the wire bonds <NUM>-<NUM>, namely, a wire bond <NUM>, a wire bond <NUM>, a wire bond <NUM>, and a wire bond <NUM> (collectively referred to herein as wire bonds <NUM>-<NUM>). The wire bonds <NUM>-<NUM> are between the signal processing device <NUM> and the printed circuit board <NUM> (e.g., the wire bonds <NUM>-<NUM> can be similar to the wire bonds <NUM>-<NUM>).

While many of the examples set forth herein include the linear micromechanical scanning silicon mirror <NUM>, it is contemplated that other types of micromechanical scanning silicon mirrors may be used. Thus, the micromechanical scanning silicon mirror <NUM> in one or more of the examples of the apparatus <NUM> can be replaced by a differing type of micromechanical scanning silicon mirror. For example, a biaxial micromechanical scanning silicon mirror can replace the micromechanical scanning silicon mirror <NUM> (e.g., the micromechanical scanning silicon mirror <NUM> can be a biaxial micromechanical scanning silicon mirror).

With reference to <FIG>, illustrated is an exemplary biaxial scanning silicon mirror <NUM> (e.g., the micromechanical scanning silicon mirror <NUM> of <FIG>). The micromechanical scanning silicon mirror <NUM> can include a mirror section <NUM>, a first foot <NUM>, a second foot <NUM>, a first flexure <NUM>, second flexure <NUM>, a third flexure <NUM>, a fourth flexure <NUM>, and a deflectable frame <NUM>. Moreover, the micromechanical scanning silicon mirror <NUM> can include a first piezoresistive sensor <NUM> and a second piezoresistive sensor <NUM> (collectively referred to herein as piezoresistive sensors <NUM>-<NUM>). The micromechanical scanning silicon mirror <NUM> can also include sensor contacts <NUM> that are electrically coupled to the piezoresistive sensors <NUM>-<NUM> (connections between the piezoresistive sensors <NUM>-<NUM> and sensor contacts <NUM> are not shown).

The first flexure <NUM> is between the mirror section <NUM> and the first foot <NUM>. A distal end of the first flexure <NUM> terminates at the first foot <NUM>. Moreover, the second flexure <NUM> is between the mirror section <NUM> and the second foot <NUM>. A distal end of the second flexure <NUM> terminates at the second foot <NUM>. In the embodiment shown in <FIG>, a proximal end of the first flexure <NUM> terminates at the deflectable frame <NUM>, and a proximal end of the second flexure <NUM> terminates at the deflectable frame <NUM>. Further, a proximal end of the third flexure <NUM> can terminate at the mirror section <NUM> and a distal end of the third flexure <NUM> can terminate at the deflectable frame <NUM>. A proximal end of the fourth flexure <NUM> can terminate at the mirror section <NUM> and a distal end of the fourth flexure <NUM> can terminate at the deflectable frame <NUM>. The first piezoresistive sensor <NUM> can be located at the distal end of the first flexure <NUM>. Moreover, the second piezoresistive sensor <NUM> can be located at the distal end of the third flexure <NUM>.

It is to be appreciated that other shapes, orientations, and designs of micromechanical scanning silicon mirrors (including other biaxial micromechanical scanning silicon mirrors) may be used.

<FIG> illustrate exemplary methodologies relating to assembling an apparatus that includes a signal processing device collocated with a micromechanical scanning silicon mirror. While the methodologies are shown and described as being a series of acts that are performed in a sequence, it is to be understood and appreciated that the methodologies are not limited by the order of the sequence. For example, some acts can occur in a different order than what is described herein. In addition, an act can occur concurrently with another act. Further, in some instances, not all acts may be required to implement a methodology described herein.

<FIG> illustrates a methodology <NUM> for assembling an apparatus that includes a signal processing device collocated with a micromechanical scanning silicon mirror. At <NUM>, a frame can be provided. At <NUM>, the micromechanical scanning silicon mirror can be mounted on the frame. For instance, feet of the micromechanical scanning silicon mirror can be mounted on the frame. At <NUM>, the signal processing device can be mounted on the micromechanical scanning silicon mirror. For instance, the signal processing device can be mounted on one of the feet of the micromechanical scanning silicon mirror.

With reference to <FIG>, illustrated is another methodology <NUM> for assembling an apparatus that includes a signal processing device collocated with a micromechanical scanning silicon mirror. At <NUM>, a frame can be provided. At <NUM>, the micromechanical scanning silicon mirror can be mounted on the frame. The micromechanical scanning silicon mirror can include a piezoresistive sensor and sensor contacts, where the sensor contacts are electrically coupled to the piezoresistive sensor. At <NUM>, the signal processing device is provided. The signal processing device can be mounted on the micromechanical scanning silicon mirror, mounted on the frame, or mounted on a printed circuit board. At <NUM>, wire bonds can be directly connected between the sensor contacts of the micromechanical scanning silicon mirror and the signal processing device.

As used herein, the term "exemplary" is intended to mean "serving as an illustration or example of something.

Claim 1:
An apparatus (<NUM>), comprising:
a micromechanical scanning silicon mirror (<NUM>), comprising:
a mirror section (<NUM>);
a first foot (<NUM>) and a second foot (<NUM>);
a first flexure (<NUM>) and a second flexure (<NUM>), the first flexure (<NUM>) between the mirror section (<NUM>) and the first foot (<NUM>), a distal end of the first flexure (<NUM>) terminates at the first foot (<NUM>), the second flexure (<NUM>) between the mirror section (<NUM>) and the second foot (<NUM>), and a distal end of the second flexure (<NUM>) terminates at the second foot (<NUM>);
a piezoresistive sensor (<NUM>); and
sensor contacts (<NUM>, <NUM>, <NUM>, <NUM>), the sensor contacts (<NUM>, <NUM>, <NUM>, <NUM>) electrically coupled to the piezoresistive sensor (<NUM>);
a signal processing device (<NUM>);
wherein the signal processing device (<NUM>) is mounted on the first foot (<NUM>) of the micromechanical scanning silicon mirror (<NUM>); and
characterized in that:
the apparatus further comprises wire bonds (<NUM>, <NUM>, <NUM>, <NUM>) directly connected between the sensor contacts (<NUM>, <NUM>, <NUM>, <NUM>) of the micromechanical scanning silicon mirror (<NUM>) and the signal processing device (<NUM>); and
the micromechanical scanning silicon mirror (<NUM>) and the signal processing device (<NUM>) are part of separate dies.