Patent Publication Number: US-2022221251-A1

Title: Digital reticle system

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of co-pending U.S. non-provisional patent application Ser. No. 17/127,771 titled DIGITAL RETICLE AIMING METHOD, filed Dec. 18, 2020, which is a division of U.S. non-provisional patent application Ser. No. 16/158,062, titled BALLISTIC AIMING SYSTEM WITH DIGITAL RETICLE, filed Oct. 11, 2018, now U.S. Pat. No. 10,907,934, which is a non-provisional of and claims benefit from U.S. Provisional Application No. 62/571,173, filed Oct. 11, 2017, titled “BALLISTIC AIMING SYSTEM WITH DIGITAL RETICLE,” the disclosures of all of which are incorporated herein by reference in their entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     Riflescopes are mounted to rifles to assist a shooter, or user, in aiming the rifle to hit a desired target. Riflescopes may include reticles, which are markings or other indicators that appear in the field of view over the image of target through the riflescope. Reticles may include horizontal and vertical crosshairs with a central intersection point that can be calibrated to coincide with the point of impact of a projectile from the rifle. This central aiming point of the reticle may be zeroed-in at a particular zero range distance and then adjusted for different ranges and conditions using elevation and windage turrets to make slight adjustments to its vertical and horizontal position relative to the rifle. In this way, the user may always use the central intersection point of the crosshairs to aim the riflescope, and thus, the rifle. However, making mechanical adjustments to these elevation and windage turrets takes time, which may be disadvantageous in the field where a desired target could move at any time. Additionally, there are detailed reference charts the user must reference or memorize to correctly adjust these elevation and windage turrets. 
     As an alternative to the fine mechanical adjustments of elevation and windage turrets, some reticles are printed or formed with set holdover points, to use as aiming points instead of the central point. These holdover points save the user time in not having to make mechanical adjustments to dials, but still include complex charts to consult or memorize, which can cost the user time in the field and may result in mistake. 
     Embodiments of the invention address these and other limitations of the prior art. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a ballistic aiming system, including a digital reticle riflescope mounted to a rifle and a device running a ballistics solution application according to embodiments of the invention. 
         FIG. 2  shows a ballistic aiming system, including a digital reticle riflescope and a rangefinder with a built-in ballistics solution calculator application according to embodiments of the invention. 
         FIG. 3  is an example block diagram of a ballistic aiming system, including a digital reticle riflescope mounted to a rifle, a rangefinder with a built-in ballistics solution calculator, a device running a ballistics solution app, and peripheral sensors according to embodiments of the invention. 
         FIG. 4A  shows an example ballistic trajectory. 
         FIG. 4B  shows another example ballistic trajectory. 
         FIG. 4C  shows an example ballistic trajectory as well as a calculated deviation from the ballistic trajectory. 
         FIG. 5  shows a cross-sectional view of an example digital reticle riflescope according to embodiments of the invention. 
         FIG. 6  shows a wiring schematic view of an example digital reticle according to embodiments of the invention. 
         FIG. 7  shows a mechanical reticle within the field of view of an example digital reticle riflescope. 
         FIG. 8  shows a digital reticle with LEDs overlaid on the mechanical reticle within the field of view of the digital reticle riflescope of  FIG. 7  according to embodiments of the invention. 
         FIG. 9  is a detailed portion of the field of view of the digital reticle riflescope of  FIG. 8 , including the mechanical reticle with crosshairs and the digital reticle with LEDs according to embodiments of the invention. 
         FIG. 10  is the detailed portion of the field of view of the digital reticle riflescope of  FIG. 9  with a central LED lit according to embodiments of the invention. 
         FIG. 11  is the detailed portion of the field of view of the digital reticle riflescope of  FIG. 9 , displaying a ballistics solution for a set of ranges through selectively lit LEDs according to embodiments of the invention. 
         FIG. 12  is the detailed portion of the field of view of the digital reticle riflescope of  FIG. 9 , displaying a ballistics solution through selectively lit LEDs that act as aiming adjustment points according to embodiments of the invention. 
         FIG. 13  shows an example digital reticle riflescope with a power selector ring and an LED indicator according to embodiments of the invention. 
         FIG. 14  shows the field of view of an example digital reticle riflescope, displaying a ballistic solution through the lit central LED at a low magnification power level according to embodiments of the invention. 
         FIG. 15  shows the field of view of the digital reticle riflescope of  FIG. 14 , displaying the ballistic solution through the lit LED, acting as an aiming point, at a higher magnification power level according to embodiments of the invention. 
         FIG. 16  shows the field of view of the digital reticle riflescope of  FIG. 14 , at the higher magnification power level of  FIG. 15 , displaying both the ballistic solution and an anti-cant indicator according to embodiments of the invention. 
         FIG. 17  shows the field of view of an example digital reticle riflescope, displaying a ballistic solution for a set of ranges through the lit LEDs, acting as aiming adjustment points, at a low magnification power level according to embodiments of the invention. 
         FIG. 18  shows the field of view of the digital reticle riflescope of  FIG. 17 , displaying the ballistic solution for a set of ranges through the different lit LEDs at a higher magnification power level according to embodiments of the invention. 
     
    
    
     DETAILED DESCRIPTION 
     SYSTEMS 
     As shown in  FIG. 1 , a ballistic aiming system  100  may include a digital reticle riflescope  110  mounted to a rifle or other firearm  115  and a computational device  120  running a ballistics solution computer application, or app  130 . The computational device  120  may be any computing device capable of running a ballistics solution application, such as a mobile phone, tablet computer, or a specialized ballistics computer, for example. The digital reticle riflescope  110  may be paired to the device  120  running the ballistics solution application  130  over a wireless communications means, such as Bluetooth or WiFi, for example. In other embodiments the riflescope  110  may communicate to the device  120  through a wired connection. The user may input information into the ballistics solution application  130  and/or select configuration settings for the digital reticle riflescope  110 . The ballistics solution application  130  may use the input information to send a ballistics solution to the digital reticle riflescope  110 . Once a ballistics solution is sent to the digital reticle riflescope  110 , the user may view and use the ballistics solution on the digital reticle riflescope  110  without the device  120  running the ballistics solution application  130 . Ballistics information used in a ballistics calculation may include information about a cartridge, projectile, caliber, bullet weight or mass, muzzle velocity, muzzle energy, ballistic coefficient, scope height, and/or drag coefficient, for example. Other ballistics information may include zero range, target ranges, preferred drag curves or models (common examples include G1, G2, G5, G6, G7, G8, or GL), and/or twist rate. 
     As illustrated in  FIG. 2 , additionally or alternatively, the ballistic aiming system  200  may include a digital reticle riflescope  110  mounted to a rifle  115  (not shown) and a rangefinder  140  with a built-in ballistics solution calculator. The rangefinder  140  may be paired or otherwise in communication with the digital reticle riflescope  110  and may send ballistics solutions to the digital reticle riflescope  110  based on the determined range to target. The digital reticle riflescope  110  may include a receiver or input  114  to receive the data. The rangefinder  140  may have been paired to the digital reticle riflescope  110  using a separate device  120  running a ballistics solution application  130 , as shown in  FIG. 1 , where the various configuration settings were initially setup. Because the rangefinder  140  may have a built-in ballistics solution calculator, it is not necessary for the user to also have the device  120  running the ballistics solution application  130  for the system  200  to function. Rather, once paired, the rangefinder  140  may communicate directly with the digital reticle riflescope  110 . The digital reticle riflescope  110  may also include a processor  112 , which is used to select particular holdover indicators based at least in part on the received ballistics information, as described in detail below. In some embodiments the processor  112  may be embodied by a microcontroller, Application Specific Integrated Circuit (ASIC), firmware such as an FPGA, other hardware, or software or other machine codes operating on a general or special purpose processor, controller, or microcontroller. 
     Additionally or alternatively, the ballistic aiming system  300  may include all of the digital reticle riflescope  110 , the rangefinder  140 , the device  120  running the ballistics solution application  130 , and peripheral sensors that provide additional input information used in calculating the ballistics solution, as shown in  FIG. 3 . In this way, the user may have an entire network of devices in communication with each other that automatically gather data about the surrounding environment and use these conditions to calculate the most accurate ballistics solution for the user. In operation, output from any of the sensors illustrated connected to the ballistics solution application  130  or the rangefinder  140  may be used as one or more inputs to the ballistics calculation that determines the eventual ballistics solution. 
     ZEROING-IN 
     As shown in  FIG. 4A  zeroing-in a riflescope to a shooting device includes shooting at a target from a known range (e.g., 100 yards) and adjusting the position of the reticle and/or riflescope  110  relative to a rifle bore line  230  until the central aiming point of the reticle within the riflescope  110 , along an optical axis  240 , appears to the user to coincide with an actual point of impact  225  on the target. These adjustments may be made in both the horizontal and vertical directions, using the windage and elevation adjustment knobs, respectively. When properly zeroed-in, the parabolic or curved ballistic trajectory  220  of the projectile from the particular rifle  115  at the baseline environmental conditions during the zeroing-in process intersects the optical line of sight  240  of the riflescope  110  at the known zero range. 
     Through the zeroing-in process, the riflescope  110 , and thus, the optical axis  240 , becomes locked into a set position relative to the rifle bore line  230 . This set position between the riflescope line of sight  240  and the rifle bore line  230  may be exploited by using holdover points or aiming adjustment points displayed on the reticle or in the field of view of the riflescope  110  to cause the user to make adjustments θ to the angle and position of the rifle bore line  230 , which results in corresponding changes to the initial line of fire  220  of the selected projectile. 
     The zero range may be one of the pieces of ballistic data entered into the device  120  running the ballistics solution application  130 . 
     BALLISTICS 
     The ballistic trajectory  220  for the selected projectile will vary with environmental conditions, such as crosswind, pressure, temperature, density altitude, humidity, angle of incline, etc. Additionally, the ballistic trajectory  220  of a projectile from the rifle  115  will vary with the projectile characteristics, such as caliber, bullet weight, ballistic coefficient, muzzle velocity, etc. and/or with the barrel length and twist rate. 
     As shown in  FIG. 4A , the ballistic trajectory  220  is a curve that begins its initial ascent at the angle of the rifle bore line  230 . Due to gravitational forces, the projectile will undergo a certain amount of vertical bullet drop relative to the rifle bore line  230  at any point along the ballistic trajectory  220  of the projectile. 
     At the zero range, the ballistic trajectory  220  and correlated bullet drop have already been calibrated during the zeroing-in process, so that the optical axis  240  intersects the ballistic trajectory  220  at the point of impact  225 , as illustrated in  FIG. 4A . Thus, a shooter has a high degree of certainty that the shot will hit the target at the desired point. At ranges beyond (or before) the zero range, however, when the shooter aims at the same point on the target through the central aiming point along the optical axis  240  of the riflescope  110 , the intersection  225  of the ballistic trajectory  220  and the optical axis  240  will still occur at the zero range, while the actual point of impact will be lower if the bullet hits the target at all, as shown in  FIG. 4B . Note that in  FIG. 4B  the target is further from the shooter than the zero range distance. When the shooter aims at the target, but the target is farther away than the zero range distance, the projectile will miss the target, absent any other correcting factors, such as elevation differential, wind, etc. This could result in a complete miss that scares the target away, or a non-fatal shot that wounds the target and causes it run off injured before the shooter can re-calibrate and administer a kill shot. Therefore, for increased accuracy and to ensure the user is taking ethical shots at long-range targets, the ballistic aiming system automatically calculates a ballistics solution (illustrated here as an angle θ), based on multiple, real-time data inputs, thereby providing increased shooting accuracy. Alternatively, the user may select which inputs are updated manually and/or in real-time within the system as well as which variables to keep constant and/or not use within the ballistic solution calculation. The ballistic aiming system uses the ballistics solution θ to instantly visibly indicate a specifically calibrated holdover point or aiming adjustment points in the digital reticle riflescope&#39;s field of view that the user may use to aim at the desired point on the target. As shown in  FIG. 4C , the line of sight  250  along the point within the field of view of the digital reticle riflescope  110 , indicated by the ballistic aiming system, intersects with the ballistic trajectory  220  at the desired point of impact  225  on the target. 
     For given environmental conditions, selected projectile, and other user input information, the ballistics solution application  130  may compute a new ballistic trajectory  220  for the selected projectile. The ballistics solution application  130  may use stored drag curves, such as the G1, G7 curves mentioned above, and custom drag curves, empirically measured data tables, the ballistics information described above, and/or algorithms for the selected projectile to calculate the amount of vertical bullet drop at any range. 
     The ballistics solution application  130  may use the computed ballistic trajectory  220  to calculate a ballistics solution θ for a given range. The ballistics solution θ may be given in terms of the amount of angular adjustment that should be made to the rifle  115  to hit the target at the determined range. The ballistics solution θ may be a set of both an elevation angle γ and an azimuth angle φ, i.e., a horizontal component and a vertical component. The amount of adjustment in the ballistics solution θ may be given in minutes of angle (MOA), milliradian (mil or MRAD), Bullet Drop Compensation (BDC), etc. 
     Because zeroing-in the riflescope  110  to the rifle  115  results in the riflescope  110  and its optical axis  240  being set at a constant angle relative to the rifle bore line  230 , any angular adjustment θ to the riflescope  110  will result in the same angular adjustment θ to the rifle. 
     The ballistics solution θ will vary depending on the range to the target. Alternatively, if no range is input, the ballistics solution θ may be given as a set of angular adjustment values θ 100  . . . θ n  for a series of incremental ranges. For example, if the zero range was 100 yards, the ballistics solution θ could include an angular adjustment value θ 100  of 0 mil for 100 yards, since the ballistic trajectory  220  should already coincide with the optical axis  240  at the point of impact  225  for the zero range, and another angular adjustment value θ 200  of 0.62 mil for 200 yards, etc. In some embodiments, the user may choose how many and which yardage targets will be displayed on the digital reticle riflescope  110 . For instance, the user may operate the ballistics solution application  130  to elect to show holdover indicators for 3 distances, 100, 300, and 500 yards. In some embodiments the user may choose up to 8 or 10 different yardages. In operation, in some embodiments, the ballistics solution application  130  calculates different ballistic solutions θ for each of the selected yardages, and sends them to the digital reticle riflescope as separate solutions, where they are stored on the riflescope  100 . The riflescope then calculates or otherwise determines which holdover solutions to select, such as by illuminating particular LEDs, as described in detail below. 
     In addition to the zero range, the ballistics solution application  130  may store environmental conditions present during zeroing-in. For example, the ballistics solution application  130  may store multiple rifle  115  and projectile profiles, for different ammunition, zero ranges, etc. The ballistics solution application  130  may store user-entered data observed from previous engagements (DOPE) and other information that may be correlated with a particular rifle  115  and projectile profile combination. The ballistics solution application  130  may use some or all of user-entered information and/or data automatically received from peripheral sensors within the ballistic aiming system  300 , as shown in  FIG. 3 , for example. 
     RANGEFINDER 
     The rangefinder  140  may be a laser rangefinder, such as the KILO2400 available from SIG SAUER of Newington, N.H., USA, or other rangefinder. The rangefinder  140  may include a built-in ballistics solution calculator for determining a ballistics solution θ based on the determined range to the target, the selected projectile, the selected rifle, and the environmental conditions. In other words, as described above and shown in  FIG. 2 , the rangefinder  140  may be paired directly to the digital reticle riflescope  110 , and thus, may operate within the ballistic aiming system  200  without the need for the device  120  running the ballistics solution application  130 . Specifically, the rangefinder  140  may determine the range to the target and then calculate a ballistics solution θ based on the determined range and other data input by the user or received via peripheral sensor devices. 
     Additionally or alternatively, as shown in  FIG. 3 , the rangefinder  140  may be paired with both the digital reticle riflescope  110  and the device  120  running the ballistics solution application  130 . In this configuration of the ballistic aiming system  300 , the rangefinder  140  may send real-time compensation data, from the rangefinder  140  itself or from connected peripherals, to the device  120  running the ballistics solution application  130 . In this way, the user may view the real-time data streamed to the ballistics solution application  130  and updated on the screen. Thus, an additional or alternative weapon using a conventional riflescope may also benefit from the device  120  running the ballistics solution application  130 , since that weapon&#39;s profile may be selected and its ballistics solution θ displayed for the determined range and environmental conditions. This may be most advantageous for groups of hunters with spotters and multiple weapon and projectile profiles. 
     DIGITAL RETICLE 
     As shown in  FIG. 5 , the digital reticle riflescope  110  may include an objective lens assembly  102 , an ocular lens assembly  104 , an erector lens assembly  106 , elevation and windage adjustment turrets  112  and  114 , a mechanical reticle  400 , and a digital reticle  500 . 
     The digital reticle riflescope  110  includes a mechanical reticle  400  within its field of view, such as is shown in  FIG. 7 . The mechanical reticle  400  may be provided within and/or on a reticle lens, plano-plano glass, and/or electro-formed wire reticle and include a horizontal crosshair  402  and a vertical crosshair  404  that intersect in the center of the field of view along the optical axis  240  of the digital reticle riflescope  110 . For example, the horizontal and vertical crosshairs  402  and  404  of the mechanical reticle  400  may have a modified plex design, as shown in  FIG. 7 , with widths ranging from about 70 μm to about 120 μm. The horizontal and vertical crosshairs  402  and  404  of the mechanical reticle  400  form a central aiming point intersection  406  at the optical axis  240 . The shooter may use this central aiming point intersection  406  of the mechanical reticle  400  to zero-in the riflescope  110  relative to the rifle  115  through adjusting the elevation and windage turrets  112  and  114  until the optical axis  240  intersects the ballistic trajectory  220  at the zero range. 
     The digital reticle  500  may include a series of holdover indicators, such as individually addressable LEDs, that are selectively lit by a processor within the digital reticle riflescope  110 . For example, the digital reticle  500  may include 25-200 individually addressable LEDs located along the horizontal and vertical crosshairs  402  and  404  of the mechanical reticle  400 , as illustrated in  FIG. 8 . In some embodiments the holdover indicators appear only on either the horizontal crosshair  402  or vertical crosshair  404 . In other embodiments the holdover indicators appear on both the horizontal and vertical crosshairs  402  and  404 , and nowhere else on the digital reticle  500 . The LEDs may be arranged within a clear substrate, shaped to cooperate with the mechanical reticle  400  and its containing structure, and connected to power and the processor through leads, as shown in  FIG. 6 . The leads may be grouped together in sets of 5-10, which may run horizontally, parallel with the horizontal crosshair  402 , from the edge of the field of view to the corresponding groups of LEDs, connecting them for selective illumination by the digital reticle riflescope  110 . For example, 72 LEDs may be grouped into 12 sets of 6, where each set has a grouping of 6 connector leads, each about 7 μm thick with about 10 μm spacing between, that run from the vertical crosshair  404  either to the left or to the right, so that the connector lead groupings form only 6 lines, each about 0.078 mm thick with about 0.7 mm spacing between, crossing the entire field of view, as shown in  FIG. 6 . These leads are not readily visible, but rather may have some level of transparency within the field of view of the digital reticle riflescope  110 , although the LEDs themselves would be visible, were they not blocked by the wider horizontal and vertical crosshairs  402  and  404  of the mechanical reticle  400  behind them. Additionally or alternatively, the connector leads may run vertically, parallel to the vertical crosshair  404 , although this may appear blurrier than the horizontally oriented leads. 
     The LEDs may be non-transmissive OLEDs arranged atop the mechanical horizontal and vertical crosshairs  402  and  404 . The OLEDs may be around 40 μm, for example, with about a 30 μm dot size. The dot pitch for the OLEDs may be 0.056 mm, for example, and may vary depending on the location along the horizontal and vertical crosshairs  402  and  404  of the mechanical reticle  400 . The OLEDs may have a very thin cathode deposition layer with a transparency of under 5%, for example. Additionally or alternatively, the LEDs may be TOLEDs with 60% transmission. Advantageously, however, the LEDs need not be transparent nor transmissive due to their arrangement atop the horizontal and vertical crosshairs  402  and  404  of the mechanical reticle  400 . This allows for cost savings and less expensive manufacture of the digital reticle  500 . Embodiments of the invention may work with any appropriate indicator or lighting technology, and is not limited to any particular technology. 
     The LEDs may be arranged on or adjacent the containing structure of the mechanical reticle  400 , which may be located in the first and/or second focal plane, for example, near the objective and/or ocular lens of the riflescope  110 . To enable the user to view the LEDs when lit, the LEDs may be located on the side of the mechanical reticle  400  closer to the ocular lens and oriented to illuminate in the direction of the ocular lens along the optical axis, as shown in  FIG. 5 . If the mechanical reticle  400  is located in the first focal plane, the riflescope  110  may light LEDs corresponding to a ballistic solution θ and those same LEDs may remain lit throughout all magnification powers of the riflescope  110 . Additionally or alternatively, the mechanical reticle  400  may be located in a different focal plane than some or all of the LEDs. 
       FIG. 8  shows the digital reticle  500  atop the mechanical reticle  400  in the field of view of the digital reticle riflescope  110 . The digital reticle  500  includes a central LED  506  that is co-located with the central aiming point intersection  406  of the mechanical reticle  400  and the optical axis  240  of the digital reticle riflescope  110 . Vertical or elevation adjustment LEDs  504  of the digital reticle  500  are located along the vertical crosshair  404  of the mechanical reticle  400  and may be lit to provide the corresponding vertical aiming adjustment of the ballistics solution θ to compensate for bullet drop. Horizontal or windage adjustment LEDs  502  of the digital reticle  500  are located along the horizontal crosshair  402  of the mechanical reticle  400  and may be lit to provide the corresponding horizontal aiming adjustment of the ballistics solution θ to compensate for crosswind, as described below. The digital reticle  500  may also include anti-cant indicators  508  along the side edges of the horizontal crosshair  402  that alert the user to rotate the rifle  115 , independently of the ballistics solution θ. Such cant systems are described in U.S. patent application Ser. No. 15/220,254, entitled Optical System with Cant Indication and U.S. patent application Ser. No. 15/372,877, entitled Optical System Accessory with Cant Indication, both of which are incorporated by reference herein.  FIG. 9  shows a more detailed view of the digital reticle  500  atop the mechanical reticle  400  in the central portion of the digital reticle riflescope&#39;s field of view from  FIG. 8 . 
     In operation of the digital reticle, the holdover indicator LEDs are lit to provide aiming adjustment points for the user. The particular holdover indicators that are energized may be selected by a processor  112  located on or in communication with the digital reticle riflescope  110  ( FIG. 3 ). An aiming adjustment point indicates to the user how far along the horizontal and vertical directions to shift the central aiming point to superimpose or align over the desired point of impact on the target. The aiming adjustment points may be located along both the horizontal and vertical crosshairs. 
     The digital reticle riflescope  110  may receive a ballistics solution θ from the rangefinder  140  or the device  120  running the ballistics solution application  130 . The ballistics solution θ may include an aiming adjustment in the form of MOA, mil, etc. for adjusting the holdover point vertically, to compensate for gravitational bullet drop, for example. The ballistics solution θ may also include an aiming adjustment in the form of MOA, mil, etc. for adjusting the holdover point horizontally, such as for wind correction. The processor  112  determines which holdover indicators are selected based at least in part on the ballistics solution θ. In other words, different ballistics solutions θ may cause the processor  112  to select different holdover indicators. The processor  112  may calculate and select which holdover indicator to energize based on the received ballistics solution. The processor  112  may determine that a particular solution falls between two discrete holdover indicators and perform a rounding function to select the closest one. As described below, the processor  112  may take into account a magnification setting of the digital reticle riflescope  110 . The processor  112  may then cause the selected holdover indicator to changes state, such as by causing electric current to flow through one or more of the selected LEDs. Aiming with the proper holdover indicator allows the shooter to properly aim at a target without making adjustments to the windage or elevation turrets, saving time and increasing efficiency and accuracy. 
     As shown in  FIG. 11 , the digital reticle riflescope  110  has lit a series of LEDs θ 100  . . . θ 700  corresponding to the ballistics solution θ for a set of incremental ranges when no range to the target has been determined, such as in the ballistic aiming system  100  of  FIG. 1  that does not include a rangefinder  140 . The user may separately determine the range to target and use the lit LEDs corresponding to incremental ranges to adjust his aim. For example, the shooter may manually estimate the range as 300 yards. The shooter would then use the third illuminated aim point down as the holdover point, since it corresponds with the pre-calculated ballistic solution θ for the rifle and projectile set at 300 yards. As described above, the number of simultaneously lit holdover indicators may be user controlled. In  FIG. 11 , the user has selected, or the system defaulted, to energizing seven separate holdover indicators. 
     As shown in  FIG. 12 , the digital reticle riflescope  110  has lit an LED along the vertical crosshair  404  to indicate a vertical aiming adjustment point  512 . Additionally in  FIG. 12 , the digital reticle riflescope  110  has lit an LED along the horizontal crosshair  402  to indicate a horizontal aiming adjustment point  514 . The vertical and horizontal aiming adjustment points  512  and  514  may be used by the shooter to quickly find the corresponding virtual holdover point  516  in the field of view of the digital reticle riflescope  110  that represents the best ballistics solution θ based on the input data. For example, the shooter may hold the central crosshair intersection over the target, take note of where the windage point  514  falls with respect to the target, then place the elevation point  512  over the place where the windage point  514  fell with respect to the target, and fire. 
     The digital reticle riflescope  110  may selectively illuminate LEDs atop the mechanical reticle  400  based on the ballistics solution θ received and the magnification level of the digital reticle riflescope  110 . 
     As shown in  FIG. 10 , when first powered on or when no ballistics solution θ has been sent to the digital reticle riflescope  110 , a central lit LED  510 , located at the optical axis  240 , may help illuminate the central aiming point  406  in low light conditions. Additionally, if the ballistics solution θ does not include a significant horizontal or vertical aiming adjustment at the particular magnification level of the digital reticle riflescope  110 , as shown in  FIG. 14 , the central lit LED  510  may indicate the best holdover aiming point for the ballistics solution θ. 
     The digital reticle  500  provides an advantage over Bullet Drop Compensator (BDC) reticles in that because the holdover points used in embodiments of the invention are dynamic, the user is not limited to only a few projectile types of similar caliber and bullet weight that match the subtension of the predefined holdover reticle markings. Rather, the digital reticle  500  may provide aiming adjustment points for any projectile types because the ballistic aiming system adapts which LEDs are illuminated based on the particular projectile profile selected or programmed. Additionally, the user need not make a custom reference chart for his rifle  115  and projectile profile, as is done with BDC reticles, because the digital reticle riflescope  110  will illuminate the exact aiming adjustment points to use for the selected profile. This feature of the digital reticle riflescope  110  enables it to be used across a variety of firearms, rather than the user having multiple riflescopes with differing BDC reticles matched to each firearm. 
     MAGNIFICATION 
     In some embodiments, the digital reticle riflescope  110  may be a variable power riflescope with a second or rear focal plane reticle. The digital reticle riflescope  110  may further selectively illuminate LEDs based at least in part on the magnification power level of the riflescope  110 . The magnification power level may be determined using an encoder, sensors, mechanical position indicators, etc. as the user increases or decreases the magnification power. In this way, even if the digital reticle  500  is in the second focal plane, it may dynamically display the ballistic solution θ as a function of the magnified target view over the mechanical reticle  400  that remains the same size throughout the magnification levels. In operation, the digital reticle riflescope  110  operates as described above, by receiving a ballistics solution θ and then calculating which holdover indicator should be illuminated. In embodiments of the invention that include magnification compensation, the processor  112  takes the present magnification setting into account when calculating which holdover indicator to illuminate. As described above, the magnification power level may be determined using an encoder or sensor, etc., and the determined power level is then communicated to the processor  112 . 
     As shown in  FIG. 14 , the lit central LED  510  in the field of view of the digital reticle riflescope  110  indicates the best holdover aiming point for the ballistics solution θ at the lower magnification power level. When the user zooms in, however, as shown in  FIG. 15 , the lit LED indicates the vertical aiming adjustment point  512  as the best holdover aiming point for the same ballistics solution θ, but at a higher magnification power level. In this way, the digital reticle riflescope  110  advantageously allows the user to make finer adjustments to his rifle  115  according to the ballistics solution θ, using dynamic holdover aiming points for the same ballistics solution θ line of sight  250  at increasing magnification power levels. Additionally,  FIG. 16  shows the same vertical aiming adjustment point  512  at the same magnification power level of  FIG. 15 , but with the LevelPlex system of the digital reticle riflescope  110  switched on to provide feedback to the user about rifle cant, independently of the ballistics solution θ. 
     POWER SELECTOR RING 
     As shown in  FIG. 13 , the digital reticle riflescope  110  may include a power selector ring  150  for altering the magnification power level of the riflescope  110 . The greater the magnification power level, the larger the image of the target within the field of view will appear. 
     The power selector ring  150  may include an encoder, a zoom sensor, or other method of determining the selected magnification power level for the riflescope  110  at any given time. The encoder may send a magnification signal to a processor within the riflescope  110 . The magnification signal may include data about the selected and/or last magnification power level of the riflescope  110  and/or power selector ring  150 . Based on the magnification signal, the processor may determine which LEDs to selectively illuminate on the digital reticle  500  to compensate for the new and/or changed magnification power level. 
     For example, as shown in  FIG. 17 , the digital reticle riflescope  110  has lit LEDs indicating a horizontal aiming adjustment point  514  on the horizontal crosshair  402  and a series of vertical aiming adjustment points, including θ 700 , on the vertical crosshair  404 , corresponding to both the lower magnification power level and the ballistics solution θ for a set of ranges and determined crosswind. When the user turns the power selector ring  150  to increase the magnification power level, as shown in  FIG. 18 , the digital reticle riflescope  110  changes which LEDs are lit for the same ballistics solution θ in response. As shown in  FIG. 18 , the horizontal aiming adjustment point  514  is located further to the right along the horizontal crosshair  402  and the vertical aiming adjustment point θ 700  is located further down on the vertical crosshair  404 . Even though the holdover aiming point  516  of  FIG. 18  has shifted down and to the right from the holdover aiming point  516  of  FIG. 17 , the corresponding line of sight  250  through the holdover aiming point  516  has not changed, since the ballistics solution θ (i.e., the relative rifle  115  orientation) is the same. 
     The power selector ring  150  may include an LED or other indicator  155  that is oriented to illuminate in the direction of the user, as shown in  FIG. 13 . The LED indicator  155  may illuminate when the digital reticle riflescope  110  is wirelessly paired with the rangefinder  140  and/or device  120  running the ballistics solution application  130  over Bluetooth or other communications means. Additionally, the LED indicator  155  may flash for various counts, set times, and/or frequencies to indicate different states to the user. Additionally or alternatively, the LED indicator  155  may change colors to indicate different states to the user. For example, the LED indicator  155  may flash at a slower frequency when the user is configuring the digital reticle riflescope  110  through the ballistics solution application  130  running on a paired device  120 . As another non-limiting example, the LED indicator  155  may flash five times at a more rapid frequency and then remain constantly on for five seconds to indicate to the user that a target is being ranged using a paired rangefinder  140  and a new ballistics solution θ has been received by the digital reticle riflescope  110 . The LED indicator  155  may have its brightness, color, and/or power controlled or set by the user through controls on the digital reticle riflescope  110  and/or configuration settings within the ballistics solution application  130 . Additionally or alternatively, the LED indicator  155  may be located elsewhere on the digital reticle riflescope  110 , such as on the diopter adjustment ring or within the field of view through the ocular lens, for example. In this way, the LED indicator  155  advantageously signals to the user that the digital reticle riflescope  110  is ready to be used with the latest ballistics solution θ without the user having to move out of shooting posture. 
     All described embodiments and features of the disclosed invention may be combined with each other in any arbitrary manner, except where as described to be exclusive or known to those of skill in the art as technically unable to be combined. The above description is meant to be read broadly, and in a non-limiting manner, and the invention is limited only by the scope of the claims below.