Dennis Olson, O.D.
Dennis Olson, O.D. is a provider specialising in Vision Therapy Optometrist in San Jose, CA, registered under NPI 1699749697. This provider registers 2 separate taxonomy codes, which usually means they practise across more than one recognised specialty. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.
Getting there
The practice address on file is 5710 CAHALAN AVE BLDG 2, San Jose, CA 95123. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| OPT 05920T | CA | Vision Therapy Optometrist primary |
| OPT 05920T | CA | Optometrist |
This provider holds licence OPT 05920T issued in CA. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
- Status
- Approved
- Provider type
- Practitioner - Optometry
- PAC ID
- 1951556752
Medicare enrolment is recorded as approved under the provider type Practitioner - Optometry. This means the provider is enrolled to bill Medicare, though it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
What Vision Therapy covers
Optometrists who specialize in vision therapy as a treatment process used to improve vision function. It includes a broad range of developmental and rehabilitative treatment programs individually prescribed to remediate specific sensory, motor and/or visual perceptual dysfunctions. NUCC Health Care Provider Taxonomy, code 152WV0400X
All registered taxonomy codes
This provider registers 2 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 152WV0400X | Vision Therapy Optometrist Vision Therapy | OPT 05920T | CA | primary |
| 152W00000X | Optometrist | OPT 05920T | CA |
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1699749697 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Feb 15, 2006 |
| Last updated | Sep 11, 2025 |
| Status | Active |
| Sole proprietor | Yes |
| Credential | O.D. |
| Practice address |
5710 CAHALAN AVE BLDG 2 San Jose, CA 95123 (408) 229-2020 Fax (408) 227-5056 |
| Other identifiers |
SD0059200
(CA) |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 6 | 9 | 9 | 7 | 4 | 9 | 6 | 9 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 6 | 9 | 9 | 5 | 4 | 9 | 6 | 9 |
Sum = 83 · next multiple of 10 = 90 · check digit = 7 · actual last digit = 7
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.