finished & coated Paraboloidal Primary Mirrors

Engineered Dream zeroDELTA lightweight mirrors

Produced and processed in-house by Dream in Nazareth, PA


"Your company does phenomenal work. There is a lot of thought and heart that goes into your products. Dream's engineering sets their lightweight mirrors apart from competitors. Your engineering goes beyond the lightweight aspect. You focus on actual performance!"

- Ted Kamprath: 39 years in professional optics, using everything from million dollar test rooms to 144" Continuous Polishers.


 
 
 
 
 

 
 
 
 
 

Print through FEA: design iteration 7 (left - 58nm) versus the final iteration; 23rd (right - under 5nm).
 
 
 
 
 

January 5th, 2018 

Click above to see amazing videos and the quality of a recently finished 20" f3.5 primary mirror.
 
 
 
 
 

Download the Dream TTC calculator to use the "feature" column in the chart to the right.

This will allow you to compare different mirrors to each other.
 
 
 
 

Modern Optical Metrology

- Dream zeroDELTA lightweight paraboloidal mirrors -
* Bubble-free
* 100% high-temp cast mirrors
***- The zeroDELTA lightweight mirrors don't have to act like one piece of glass. Through high-temperature
******casting, they are one piece.
***- Elimination of historically troublesome bond-line and consistency (mirror to mirror) issues that plague
******lower-temp fused and frit-bonded lightweight mirrors, even for those with 20-30+ years experience
******producing them.
***- zeroDELTA lightweight mirrors won't come apart or change figure today, tomorrow or 10 years from now.

 
* All mirrors have a plano (flat) back, using back flange designs
***- Allows for simple/conventional mirror supports.
***- Back flanges create semi-closed back, producing a stiffer mirror that can still equalize exceedingly fast.
* zeroDELTAmirrors use the thinnest features of any off-the-shelf lightweight mirror in history
***- Mirrors are 70-80% lower in weight than same diameter, profile & edge height solid mirror.
***- A domino effect of mechanical improvements occur with the zeroDELTAengineered lightweight mirror; less
******self-weight deflection, less flexure from mirror mount, less flexure from backplate and telescope. Maintain
******tight optical alignment tolerances that come with today's faster mirrors & systems; higher mechanical
******performance of the total telescope.
***- Elimination of quality-robbing boundary-layer mirror seeing; a centuries old problem with all solid mirrors.
***- Mirror seeing and tube currents eliminated due to industry-leading thermal time constant performance of
******Dream's zeroDELTAmirrors.
 

Thermal Time Constant - Same Edge Height Solid Mirrors Compared To 16" zeroDELTA

quartz

ULE

Zerodur

borosilicate

BK7

AstroSittal

plate glass

306x

336x

360x

400x

490x

497x

648x

slower 

slower

slower

slower

slower

slower

slower
 
***- Elimination of figure-distortion caused by internal temperature gradients, making zeroDELTA™ mirrors
******process & finish to the same quality levels as zero-expansion mirrors, as proven by other professionals
******outside Dream who have each finished hundreds of solid Zerodur mirrors over their 30-45 year careers.
***- Zero & near zero-expansion solid mirrors still have thermal mass. A mirror material's Coefficient of Thermal
******Expansion (CTE) has nothing to do with boundary layer losses, which still remain for all solid and thick-
******featured mirrors.
* Unprecidented level of engineering with 15 years of heritage
***- Intelligent designs, implementation and technology that provides truly cutting-edge total performance,
******without the typical print-through baggage that has historically come with lightweight mirrors.
***- Dream's owner (Shane Santi) has been learning about lightweight mirrors for more than 25 years and
******designing them based on FEA feedback iterations for the past 15 years.
***- Engineering analysis evaluates; polishing displacements (print through) & gravity displacements (final use).
***- Designs are run through as many as 30 iterations. Design changes are evaluated after each iteration.
***- High level of engineering allows zeroDELTA mirrors to have extremely low (L/100 PV or better)
******print through; Mid-Spatial Frequency (MSF) / "primary ripple." Dream's internal polishing also
******averages 6-9Å surface roughness (smallest-scale errors). Dream has finished primary mirror aspheres
******to as close as 0.009% in radius.
* All of the above at 6-10x lower cost than pocket-milled zero-expansion lightweight mirrors.
 

size

f-ratio

FL

height

feature

weight

price

10"

6

1525mm

36mm

3.2mm

3.6 lbs

contact Dream

12.5"

4.8

1525mm

45mm

3.2mm

5.4 lbs

14.5"

4.1

1525mm

54mm

3.2mm

8.2 lbs

16"

3.0

1219mm

63.5mm

3.2mm

9.5 lbs

16"

3.75

1525mm

63.5mm

3.2mm

9.7 lbs

20"

3.0

1525mm

78mm

4mm

20 lbs

20"

3.5

1780mm

78mm

4mm

21 lbs

24"

3.0

1830mm

87mm

5mm

34 lbs

24"

3.5

2135mm

87mm

5mm

35 lbs

28"

3

2135mm

102mm

6.5mm

57 lbs

32"

3

2438mm

116mm

8mm

88 lbs

36"

3

2743mm

130mm

9mm

131 lbs

40"

3

3050mm

145mm

9mm

157 lbs
             

Standard coating is enhanced aluminum; 96% or greater reflectivity at 550nm wavelength.

Pricing, availability and specifications subject to change without notice.


High Performance Doesn't Fear Change. It Defies The Status Quo.

Custom Mirrors Available
* Dream has produced mirrors as fast as f1.3 and R-C optical sets with system f-ratios as fast as f3.
* Also available; spheroids, hyperboloids, convex, plano, finished Cassegrain optical sets, dedicated athermal carbon fiber mirror mounts, all the way to finished telescopes. Contact Dream to discuss your needs.

10" f3 perforated

"Can I say: holy cow!! This looks awesome!!"

- European telescope manufacturer

 

Survey/Search Telescope
32" f4.2 Dream R-C: fast, compact & highly corrected Ritchey-Chretien telescope for large (61.4mm/side) detector: survey, NEO, etc. Click here to learn more about this wide-field, high-throughput science telescope, camera and mount combination.
 

Custom Cassegrain Telescopes

24" f12 Dream R-C: NASA

   
   

16" f2 Dream Cassegrain: IRetelescope with 6-lens IR relay, 2 each - Ge, ZnS & ZnSe, dual-band performance: USAF

   
   

25" Cassegrain Telescope: Structure only, for solid ULE M1 & M2: Turkey


Dream can produce carbon fiber structures for zero-expansion optical sets, as well as full telescopes ranging from f2.0 to f20+, from UV to far IR. Click here to see our standard line of incredibly light R-C telescopes or Contact Dream to discuss your project's custom requirements.


pricing, availability and specifications subject to change without notice

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